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Digital Object Identifier 10.1109/MELE.2019.2916528
IEEE
VOL. 7, NO. 2
JUNE 2019
ISSN 2325-5987
WWW.IEEE-PES.ORG/
MAGAZINE
F E AT U R E S
12
Flexibility in Sustainable
Electricity Systems
40
Multivector and multisector
nexus perspectives.
High value for capabilities
beyond one-way managed
charging.
Eduardo Alejandro Martínez Ceseña,
Nicholas Good, Mathaios Panteli,
Joseph Mutale, and
Pierluigi Mancarella
22
Electric Vehicles
in Latin America
Slowly but surely toward
a clean transport.
Jairo Quirós-Tortós,
Luis Victor-Gallardo, and
Luis (Nando) Ochoa
33
Electric Vehicles and
Climate Change
Potential Benefits
of Vehicle-to-Grid
Technology in California
Jonathan Donadee, Robbie Shaw,
Oliver Garnett, Eric Cutter,
and Liang Min
46
Will Electric Vehicles
Drive Distribution
Grid Upgrades?
The case of California.
Jonathan Coignard,
Pamela MacDougall,
Franz Stadtmueller,
and Evangelos Vrettos
Additional contributions
and improved economic
justification.
Hamidreza Nazaripouya,
Bin Wang, and Doug Black
D E PA R T M E N T S & C O L U M N S
2
5
57
60
64
ABOUT THIS ISSUE
TECHNOLOGY LEADERS
NEWSFEED
DATES AHEAD
VIEWPOINT
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Page 59.
Cover image: Realizing a carbon-free future
for the planet will require flexible, sustainable
energy systems.
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MISSION STATEMENT: IEEE Electrification Magazine is dedicated to disseminating information on
all matters related to microgrids onboard electric
vehicles, ships, trains, planes, and off-grid applications. Microgrids refer to an electric network in a
car, a ship, a plane or an electric train, which has a
limited number of sources and multiple loads. Offgrid applications include small scale electricity supply in areas away from high voltage power networks. Feature articles focus on advanced concepts, technologies, and practices associated with
all aspects of electrification in the transportation
and off-grid sectors from a technical perspective in
synergy with nontechnical areas such as business,
environmental, and social concerns.
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Promoting Sustainable Forestry
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SFI-01681
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
ABOUT THIS ISSUE
Electrify to
Decarbonize
By Manuel Avendaño
XTREME WEATHER AND FAILURE TO MITIGATE AND
adapt to climate change are the gravest threats facing
the world, according to the World Economic Forum’s
2019 Global Risks Report. The year 2018 reminded us that climaterelated disasters—namely, storms, fires, and floods—are becoming more severe and happening more often. Meanwhile, the
United Nations’ Intergovernmental Panel on Climate Change
has issued a special report on the impacts of global warming of
1.5 °C above preindustrial levels, which could trigger more
extreme events.
In the United States, the National Climate Assessment, a report
from 13 government agencies, described the far-reaching implications of climate change and concluded that “the evidence of
human-induced climate change continues to strengthen and that
impacts are increasing across the country.” In the southwest
region of the United States (and California in particular), climate
change is exacerbating the key factors that lead to wildfires: heat,
drought, and tree-murdering insect outbreaks.
According to the California Department of Forestry and Fire
Protection, 10 of the 20 most destructive California wildfires have
happened since 2015. The 2017 and 2018 wildfire seasons demonstrated the increasing threat of wildfires to California and led to
what could be described as the first bankruptcy catalyzed by climate change. In January 2019, Pacific Gas and Electric Company,
one of the largest energy companies in the United States, filed for
bankruptcy protection, citing US$30 billion in potential liabilities
from fire-related lawsuits.
The cumulative evidence from the scientific assessment of climate change and its already palpable effects confirms that the
predicted global climate crisis has materialized. Time is running
out to implement a comprehensive climate-change response
strategy and avoid irreversible impacts. Achieving a sustainable
future requires integrated, practical, and cost-effective approaches
pursued through broad-based partnerships with governments
(local, state, federal, and tribal), businesses, organizations (including electric utilities), and individuals.
E
2
EDITORIAL BOARD
Iqbal Husain
Editor-in-Chief
North Carolina State
University
North Carolina, USA
[email protected]
Tamas Ruzsanyi
Editor, Electric Trains
Ganz-Skoda
Hungary
[email protected]
Eduardo Pilo de la Fuente
Editor, Electric Trains
EPRail Research
and Consulting
Spain
[email protected]
Jose Conrado Martinez
Editor, Electric Trains
Directcion de Estrategia
y Desarrollo
Spain
[email protected]
Suryanarayana Doolla
Editor, Microgrid
Indian Institute of
Technology Bombay
India
[email protected]
Mohammad
Shahidehpour
Editor, Microgrid
Illinois Institute
of Technology
Illinois, USA
[email protected]
Steve Pullins
Editor, Microgrid
GridIntellect
Tennessee, USA
[email protected]
Antonello Monti
Editor, Microgrid
RWTH Aachen
Germany
amonti@eonerc
.rwth-aachen.de
Marta Molinas
Editor, Electric Ships
Norwegian University of
Science and Technology
Norway
[email protected]
Herb Ginn
Editor, Electric Ships
University of
South Carolina
South Carolina, USA
[email protected]
Robert Cuzner
Editor, Electric Ships
University of
Wisconsin-Milwaukee
Wisconsin, USA
[email protected]
Chris Searles
Editor, Electric Vehicles
BAE Batteries
Wisconsin, USA
Chris.Searles@
baebatteriesusa.com
Silva Hiti
Editor, Electric Vehicles
Rivian
California, USA
[email protected]
Eduard Muljadi
Editor, Electric Vehicles
Auburn University
Alabama, USA
[email protected]
Syed A. Hossain
Editor, Electric Planes
GE Aviation
Ohio, USA
[email protected]
Kaushik Rajashekara
Editor, Electric Planes
University of Houston
Texas, USA
[email protected]
Babak Nahid-Mobarakeh
Editor, Electric Planes
University of Lorraine
France
[email protected]
Bulent Sarlioglu
Editor, Electric Planes
University of
Wisconsin-Madison
Wisconsin, USA
[email protected]
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Digital Object Identifier 10.1109/MELE.2019.2906628
Date of publication: 11 June 2019
Khwaja Rahman
Editor, Electric Vehicles
General Motors
Michigan, USA
[email protected]
IE E E E l e c t r i f i c ati o n M agaz ine / J UN E 2019
Digital Object Identifier 10.1109/MELE.2019.2906627
ELANTAS is Your Solution Provider
for Hybrid and Electric Vehicles
Increasing expert consensus shows that electrification of
energy end uses—transport, heating and cooling, industry
processes, and others—will be crucial to reach carbonemission goals and mitigate climate change. A holistic
view is required to combine energy carriers (electricity,
thermal sources, and fuels) with infrastructures, such as
transportation, water, and data networks, to achieve sustainable decarbonization based on the integration of energy systems.
In this issue, with the theme “Electrify to Decarbonize,”
researchers, industry professionals, and policy makers
from the global electricity sector provide insights into how
electrification can help other sectors and consumers decarbonize in the context of a rapidly evolving, digital world.
The issue includes broad-perspective and case-study articles covering such topics as the climate–energy nexus,
frameworks for utility-driven and policy-based electrification, grid scenarios for reducing greenhouse gas emissions,
and the electrification of end-use services in the transportation, building, and industrial sectors. The articles focus
on advanced concepts, technologies, and practices associated with electrification in a decarbonized future from a
technical perspective as well as on how to address business,
environmental, and social concerns.
This issue begins with the “Technology Leaders” column
“The Drive to Zero” by Heather Tomley of the Port of Long
Beach, which has set a goal for zero-emissions operations by
2035. This article highlights six landmark electrification projects at the second-busiest seaport in the United States. The
contribution also underscores the effectiveness of broadbased partnerships for leveraging investments in innovative
electricity ventures.
The first project includes testing more than 100 pieces of
zero-emissions equipment and trucks, developing a nearzero-emissions tugboat, and deploying two of the cleanest
vessels available. The second project represents the largest
demonstration and deployment in the United States of zeroemissions cargo-handling equipment at a single port. The
third project has three core components: establishing an
electric vehicle (EV) charging infrastructure; developing software to identify, estimate, and forecast the costs and
requirements of establishing and operating zero-emissions
terminals; and installing the world’s first dc fast-charging
system in a seaport environment.
The goal of the fourth project is to develop a microgrid
capable of isolating from the grid and protecting terminal
operations against grid failures and related losses and damage. The fifth project focuses on demonstrating three battery-electric top handlers, tested for the first time, as well as
testing to compare the performance of a hydrogen fuel cell
yard truck with a battery-electric yard truck. The sixth project involves the development of an economical, realistic
road map to EV planning for the Port and its supplychain partners.
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IEEE Elec trific ation Magazine / J UNE 2 0 1 9
3
ABOUT THIS ISSUE
The comprehensive electrification of port operations in the United States dovetails with the
multivector vision of energy flexibility being pursued in the Eastern
Hemisphere. In “Flexibility in Sustainable Electricity Systems,” by
Eduardo Alejandro Martínez Ceseña, Mathaios Panteli, and Mathaios
Panteli of the University of Manchester; Nicholas Good of Upside
Energy Ltd.; and Pierluigi Mancarella of the University of Melbourne, a
holistic approach to combining
energy carriers with an existing
energy infrastructure is described.
This article is a call to action to
rethink the role and value of flexibility in the operation of the energy
sector to leverage available resources and strategic investments for the
provision of services.
The remainder of the issue is
focused on another key electrification front: EVs that charge from an
increasingly clean electric grid to
help decarbonize the transportation sector. An assessment of the
electrification of light-duty EVs in
developing economies is offered in
“Electric Vehicles in Latin America” by Jairo Quirós-Tortós and Luis
Victor-Gallardo, both of the University of Costa Rica, and Luis (Nando)
Ochoa of the University of Melbourne. This article provides an overview of financial and nonfinancial
incentives for EVs in Latin America,
hurdles for the deployment of a public charging infrastructure, and
quantification of public charging
stations available in Mexico, Central America, and South America.
The authors also present a methodology developed in Costa Rica to
define locations for fast-charging
stations and the results of an economic assessment that sheds light
on why the pace of EV adoption in
Latin America is so slow.
Latin American countries may
tap into the accelerating vehicle
electrification efforts taking place in
California to develop their own
4
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
pathway to decarbonize the transportation sector. For example, in
“Electric Vehicles and Climate
Change,” Hamidreza Nazaripouya of
the University of California, Riverside, and Bin Wang and Doug Black
of Lawrence Berkeley National Laboratory describe the potential value
streams of EVs for owners, fleet
aggregators, electric utilities, and
transmission system operators.
Their article investigates the economic justification of EVs and their
deployment, taking into consideration the grid services provided by
EVs to improve reliability, security,
and resilience.
The potential benefits of vehicleto-grid (V2G) technology for California’s customers are examined in
“Potential Benefits of Vehicle-to-Grid
Technology in California” by Jonathan Donadee and Liang Min of the
Lawrence Livermore National Laboratory and Robbie Shaw, Oliver Garnett,
and Eric Cutter of Energy and Environmental Economics, Inc. The
results of their modeling indicate
that the grid value of deploying EVs
with bidirectional charging and discharging capabilities can be more
than four times that of one-directional flow EVs at specific locations.
This article finds that relaxing limits
on discharging the battery of EVs
would increase the electric grid value
of V2G by 32%, but the energy discharged would also increase by 47%.
The findings encourage more
research and analysis to determine
whether the additional battery wear
and tear offsets the benefits of V2G
for vehicle owners.
Support for electrification in transportation should also be evaluated
through the lens of the electric utility. This is the perspective of “Will
Electric Vehicles Drive Distribution
Grid Upgrades?” by Jonathan Coignard
and Evangelos Vrettos of Lawrence
Berkeley National Laboratory, Pamela MacDougall of the Natural Re_
sources Defense Council, and Franz
Stadtmueller of Pacific Gas and
Electric Company. The article offers a
thorough analysis of the impact of EV
charging on 39 real-world distribution feeders in Northern California.
The results are then extrapolated for
a larger set of more than 1,000 residential feeders within the service
area of Pacific Gas and Electric Company and used to determine whether
the increase in EV load will require
system upgrades, e.g., direct control
measures or indirect control mechanisms, such as economic incentives. The analyses are based on
actual distribution feeder models
used in regular utility operations.
This issue is rounded out with
the “Viewpoint” column, “Southern
California Edison’s Blueprint for Integrated Electrification” by Manuel
Avendaño and Devin Rauss of
Southern California Edison. The column outlines the utility’s integrated
approach to decarbonize the electric
power sector and transition fossilfuel-dependent sectors to clean
electric power in California. This
systematic approach, known as the
Clean Power and Electrification
Pathway, calls for the following by
2030: 80% carbon-free electricity,
more than 7 million EVs (including
light, medium, and heavy duty) in
use, and the electrification of space
and water heating for almost a third
of buildings. This blueprint, if followed, will help reduce the threat of
climate change and improve public
health related to air quality.
This issue on electrifying to decarbonize would not have been possible
without the hard work from the
dedicated authors who developed
insightful and well-written articles.
Special thanks to Editor-in-Chief
Iqbal Husain for his kind guidance
and unwavering support. We trust
this special issue of IEEE Electrification Magazine will excite readers
about the endless opportunities
for integrated electrification and
motivate them to join the cleanenergy revolution.
TECHNOLOGY LEADERS
The Drive to Zero
By Heather Tomley
HEN THE PORT OF LONG
Beach (POLB) in California
adopted the Green Port Policy in 2005, it made a permanent
commitment to sustainability and
reducing pollution from all sources
associated with port-related operations at the complex that sits at the
edge of the greater Los Angeles area
on the U.S. West Coast. The policy set
the stage for aggressive clean air programs, the success of which has led
to today’s transformational drive
toward a zero-emissions port.
Today, the POLB is at the forefront
in establishing such policies. With
our largest deployment of clean air
technologies to date, we are moving
as swiftly as possible toward the full
integration of advanced technologies
into ships, trucks, trains, off-road
equipment, and small harbor craft.
The key to closing the gap is eliminating harmful emissions from
heavy-duty trucks and off-road cargohandling equipment, which operate
around the clock at the secondbusiest container seaport in the United States. The POLB, along with the
Port of Los Angeles, has set goals for
transitioning all terminal equipment
to zero emissions by 2030 and transitioning all on-road trucks calling at
the Port to zero emissions by 2035.
W
Digital Object Identifier 10.1109/MELE.2019.2906629
Date of publication: 11 June 2019
2325-5987/19©2019IEEE
The goals are outlined in the guiding document for the neighboring
Southern California ports of Long
Beach and Los Angeles—the 2017
Clean Air Action Plan (CAAP) Update.
The plan also sets targets for combating global warming and climate
change by reducing greenhouse
gases (GHGs) to 40% below 1990 levels by 2030 and 80% below 1990 levels
by 2050.
Similar to clean air initiatives that
have already resulted in unprecedented reductions of diesel particulate matter (DPM), nitrogen oxides
(NOx), and sulfur oxides (SOx), it is a
tall order the Port cannot fulfill by
itself. The cost of going fully zero
emissions is estimated at US$7–14
billion, and the challenges include
developing commercialized technology (i.e., reliable, clean equipment
and vehicles that can withstand the
demanding, real-world operations of
a busy port) and ensuring that the
infrastructure for alternative power
and fuel is prepared to keep the
machinery running.
Although the Port is technology
neutral, many of its current efforts
focus on electricity because most
recent advances for port-related
equipment have involved battery and
plug-in technologies. Consequently,
the demand for electricity is projected to quadruple, making energy
planning, management, and resilience a priority.
Pooling resources and know-how
is the Port’s path forward, exemplified
by its robust fundraising for grants to
pursue large-scale demonstrations of
zero-emissions equipment and
advanced energy systems. At the
same time, the POLB is committed to
ensuring that California’s interconnected system of trade, which
accounts for one-third of the state’s
economy in the form of more than
5 million jobs and US$740 million in
gross domestic product, remains
competitive and continues to thrive.
The partnerships we have developed and continue to build on over
the years are more critical today than
ever. Lasting progress occurs when
the manufacturers that make the
equipment and the terminal operators and trucking companies that purchase and use the equipment work
together toward clean air solutions
that make sense commercially.
This article describes in detail the
six recently launched projects the
POLB is pursuing along with a variety
of partners and stakeholders. The
projects are key components of
efforts to develop the near-zero- and
zero-emissions technology that will
allow the Port to meet its goals.
Partnering Toward Zero
The Port recently secured nearly
US$80 million in matching grants
from the California Energy Commission (CEC) and the California Air
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
5
TECHNOLOGY LEADERS
to zero emissions and its expertise in
maximizing available resources and
collaborating with private and public
sector partners. These projects—all of
which focus on meeting regional and
statewide clean air sustainability
goals, balancing them with the operational needs of the maritime and
goods movement industries, and
serving as models for other seaports,
industries and communities—are the
epicenter of how we get to zero.
Figure 1. A diesel yard tractor at the Pier J container terminal. Kalmar tractors like this will be
part of the test of battery-electric engines versus fuel-cell engines.
Figure 2. Kalmar yard tractors with battery-electric engines will be part of the
demonstration projects.
Resources Board (CARB) to move
ahead with six transformative projects. All of these involve multiple private and public partners contributing
significant resources as well as
researchers and consultants who will
collect and analyze data and report
their results. Each project has a rigorous testing and data collection period
of at least three months.
Participants include all of the
Port’s six container terminals (container cargo represents 75% of the
Port’s business). Southern California
Edison (SCE), the Port’s local electric
utility, is a partner on five projects.
The roster of participants draws
on global and regional expertise in
6
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
international trade; labor; transportation; manufacturing; engineering;
sustainability research; and energy
resource planning, analysis, and
forecasting. Education outreach and
workforce development are also
components of all six projects.
Each project will be evaluated in
terms of its benefits to adjacent commercial, industrial, and residential
zones. Areas include neighborhoods
disproportionately impacted by
emissions and traffic associated with
port operations, known as disadvantaged communities.
The level of grant support shows
how far the Port has come in terms
of the depth and breadth of its drive
Sustainable Terminals
Accelerating Regional
Transformation Project
The Sustainable Terminals Accelerating Regional Transformation (START)
project is the largest in terms of
reach and scope. With a US$50 million grant from CARB, the US$102
million project involves testing
more than 100 pieces of zero-emissions equipment and trucks at three
California seaports: Long Beach,
Oakland, and Stockton. The project
will also develop a near-zero-emissions tugboat, deploy two of the
cleanest ships to call on the West
Coast, and advance workforce development programs to support
sustainable goods movement. SCE
will play a lead role, and private sector partners will demonstrate the
equipment across the intermodal
network, including a full near-zero/
zero-emissions supply chain at
Long Beach’s Pier C in partnership
with ocean carrier Matson Navigation Company and terminal operator SSA Marine.
Specifically, the project will test
33 battery-electric yard tractors (Figures 1 and 2), one battery-electric top
handler, 16 8,000-pound batteryelectric forklifts, 10 battery-electric
400-hp class-8 trucks, nine electric
rubber-tired gantry (e-RTG) cranes,
and one all-electric rail car mover,
all of which will validate the potential to convert fleets of vehicles to
zero emissions and retain fully operational capabilities. Additionally,
18 36,000-pound battery-electric
forklifts, five battery-electric 500-hp
class-8 trucks, and two battery-electric top handlers will be deployed to
test improved performance capability at scale. Lastly, the demonstration
will leverage some of the cleanest
vessels available: two tier-three ships
and one near-zero-emissions tierfour electric-drive tugboat.
Important firsts at Long Beach
include the largest fleet of conventionally operated zero-emissions yard
tractors at a single port and the first
deployment of tier-three low-NOx
oceangoing vessels on the West Coast.
Other maritime and goods movement partners are tugboat operator
Harley Marine, trucking company
Shippers Transport Express (a subsidiary of SSA Marine), Nichols
Brothers Boat Builders, and General
Dynamics NASSCO. Original equipment manufacturers (OEMs) include
DINA, Taylor Machine Works Inc.,
Peterbilt Motors Company, Wiggins
Lift Company Inc., and Nordco Inc.
Engineering, and the technology
partners are TransPower, Cavotec,
BYD Motors Inc., Thor Trucks, and
Robert Allan Ltd.
START Yard Tractors and Trucks
DINA yard tractors and Peterbilt class
8 trucks will be equipped with stateof-the-art TransPower technology
that increases efficiency, reduces
energy consumption, and extends
the operating life of the vehicles.
TransPower’s features include
xx
automated manual transmission
software that regulates shifting
xx
onboard inverter-charger units
that improve reliability
xx
the Cell-Saver Battery Management System, which better regulates battery usage and recharging
xx
the power control and accessory
system, which combines hundreds of components into a single, easy-to-install assembly.
START Top Handlers
Taylor’s top handler will feature BYD’s
lithium-iron-phosphate batteries with
improved safety features and long life
cycles. The equipment reflects BYD’s
ongoing collaborative efforts involving
electric motors, power drive systems,
batteries, and other specialized components, which are designed to meet
end users’ precise, optimized capacities, torques, and other specifications.
START Vessels
Harley Marine, a tugboat operator,
has designed and engineered an
innovative propulsion and electrical
generation system that dramatically
reduces diesel consumption during
standard operation. Exceeding the
cleanest-available standard of tier
four, the diesel-electric hybrid system
for a tug features six Caterpillar C32
diesel engine generators (994 kW,
1,332 hp, and tier four), a power management system, two variable-frequency drives, two electric propulsion
motors, and two azimuth drives. The
electric-drive tugboat utilizes shared
load capability, operating on one
engine during low-speed transit and
on additional engines only as needed,
thus cutting diesel consumption by
more than half compared to that of
conventional tugs. Because it can run
exclusively on electricity, the electricdrive system also creates a model
operating system for integrating battery technology.
Matson is investing nearly US$1
billion to modernize its Hawaii service, including two of the largest
container ships ever built in the
United States and two tier-three
low-NO x ships (Figure 3). The
engines will be equipped with selective catalytic reduction (SCR) technology with urea injection and
exhaust gas recirculation (EGR).
While SCR and EGR are standard
components of tier-three engines for
land applications, this will be the
first application for marine engines
used in West Coast operations.
START Infrastructure
START also involves building charging infrastructure. Seven charging
stations will be installed for this project, with five directly adjacent to
Shippers Transport Express and two
at the Clean Trucks Program Terminal
Access Center. The latter will be the
first publicly available heavy-duty
truck charging stations in the South
Coast Air Basin. Oakland and Stockton will manage installation of
charging infrastructure at their
respective ports.
The START project is part of California Climate Investments, a California-wide initiative investing
billions of cap-and-trade dollars into
reducing GHGs, strengthening the
Figure 3. The Matson Shipping Company’s newest ship, the Daniel K. Inouye, is the largest container ship ever built in the United States. The only tier-three container ship to call regularly at
the POLB, it is part of the START project for a near-zero supply chain centered at POLB’s Pier C.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
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TECHNOLOGY LEADERS
from rubber with inlaid steel reinforcement, which lies over a channel
cast in the dock.
Zero-Emissions Yard Tractors
ITS will work with BYD to deploy
seven all-electric yard tractors. The
LBCT will deploy an additional five
battery-electric yard tractors, for a
total of 12 units in the demonstration. Two yard tractors will be compatible with an automated “smart”
yard tractor charging system to test
the fast, large-scale charging system
needed to transition the fleet to
zero emissions.
Figure 4. Diesel-powered RTG cranes at Pier J at the POLB. Cranes like these will be retrofitted to run on electricity. These will stack and sort cargo in the container yard.
economy, and improving public
health and the environment. Under
the workforce development component, the Port will share lessons
learned with Long Beach City College
(LBCC) and the Long Beach Unified
School District and support related
education and workforce programs
with school districts and community
colleges in Oakland and Stockton.
The project is due to be completed
by June 2021.
Zero-Emissions Terminal
Equipment Transition Project
With a US$9.7 million grant from the
CEC, this US$13.7 million project involves 25 pieces of new and repowered off-road cargo-handling
equipment and trucks. The total includes nine e-RTGs being repowered
at Pier J and four liquefied natural gas
(LNG) fuel drayage trucks equipped
with plug-in hybrid technology. The
project represents the nation’s largest demonstration and deployment
of zero-emissions cargo-handling
equipment at a single port.
The Port is partnering with three
terminal operators to test the equipment: International Transportation
Service (ITS) at Pier G, Long Beach
Container Terminal (LBCT) at Middle
Harbor, and Pacific Container Terminal
8
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
Zero-Emissions Hybrid-Electric
Trucks
(operated by SSA Marine) at Pier J.
Other partners include drayage
trucking company Total Transportation Services, Inc. (TTSI); OEM partners and technology vendors Cavotec,
BYD, and U.S. Hybrid Corporation;
and SCE and natural gas provider
Clean Energy Fuels Corporation.
TTSI will work with US Hybrid to
repower four underpowered 9-L Class 8
drayage LNG trucks. US Hybrid will
convert the underutilized trucks to
plug-in hybrid electric and use geofencing to operate in zero-emissions mode
within the Port. Those same trucks will
still be able to run on natural gas, with
extended-range LNG capability.
Zero-Emissions RTG Cranes
Zero-Emissions Infrastructure
SSA Marine is working with Cavotec
to repower nine existing ZPMC diesel-electric RTGs—the nation’s largest deployment of fully electric
RTGs—by replacing their onboard
diesel engines with a grid-connected
electric conversion system and a battery package that enable disconnection from the grid and blocks
changing during normal operations.
(Figure 4). While grid-connecting
equipment is not new, Cavotec provides an innovative motorized cable
management system that ensures
reliable delivery of power, data, and
communications. By locating the
feed point for the cable in the center
of the container block, the technology allows the e-RTG to move in both
directions from the feed point. The
cable reels are located underground
in Cavotec’s Panzerbelt, a cable protection system incorporating a continuous semiflexible belt fabricated
SCE will work with the Port to complete
approximately US$3.45 million in infrastructure upgrades to provide power to
24 charging points for the electric yard
tractors and electrical infrastructure
that support the e-RTGs. SCE is building the infrastructure for the charging
points (with a total load of 5 MVA) on
the west side of Pier G, with service
from a local SCE substation. Features
include two pad-mounted switches,
one pad-mounted capacitor bank, and
two 2,500-kVA transformers (12–
480 kV) as well as a meter cabinet, conductor, and six slab boxes.
SCE is also designing, installing,
and maintaining the electric infrastructure for powering the e-RTGs. Its
infrastructure will include a new
12-kV circuit in an existing wharf
substation, a new pad to house 12-kV
switchgear, a new four-way remoteactuated gas switch, a vault upgrade,
and three new meters. SCE will
distribute the two 12-kV circuits to
two new substations near the proposed e-RTG stacking runs. These
substations would transform the
12 kV to 4,160 V and then distribute
the 4,160 V circuits to two termination points—one for each RTG stacking run—for a total of four 4,160-V
termination points. SSA Marine will
be connecting the e-RTGs to the grid
at these points.
The project includes a first-inthe-nation battery package replacing the onboard auxiliary diesel
engines allowing the e-RTGs to
unplug from the grid and move
from one container stack to another
during normal operations. The
package will be contained within a
20-ft cargo container.
Ten battery-electric yard trucks
will use 200-kW charging stations
from BYD. The project will install six
of these chargers at a central location
on Pier G for ITS and four at Middle
Harbor for the LBCT. Although there
will initially be only six at Pier G for
ITS, the new infrastructure being
installed by SCE will support up to 20.
These high-powered chargers will
enable the terminals to overcome a
key barrier to widespread market
adoption of zero-emissions technologies, i.e., the ratio of charge time to
operating time, so that yard trucks
can meet the real-world minimum
requirements of two shifts per day.
Under a separate funding stream,
ITS and the LBCT will each install a
100-kW “smart charger,” supporting
the fast, large-scale charging system
while transitioning its fleet to zero
emissions. Innovations include
charging “arms,” which intelligently
engage with a properly modified yard
tractor and disengage when charging
is complete.
The plug-in hybrid trucks will be
equipped with onboard chargers.
TTSI will also install two transformerequipped charging stations, where
the trucks can plug in and recharge.
The trucks will be able to refuel at
TTSI’s on-site LNG fueling stations as
well as at nearby Clean Energy, which
offers Redeem, the first commercially
available LNG vehicle fuel.
The workforce development component of the Zero-Emissions Terminal Equipment Project will assess the
existing skills of the region’s workforce and expand training programs
for jobs that support the Port’s transition to zero-emissions equipment.
The Port’s partners are LBCC and the
International Brotherhood of Electrical Workers (IBEW). The project is due
to be completed in late 2020.
Port Advanced Vehicle
Electrification Project
The Port Advanced Vehicle Electrification Project (PAVE) focuses on strategic, cost-effective solutions for future
deployments of charging and alternative fuel infrastructure in zero-emissions cargo-handling equipment.
Total Terminals International (TTI),
SCE, TransPower, and the IBEW are
among the partners. Others include
ChargePoint, Inc., a leading electric
vehicle (EV) charging network; Kalmar Global, a leading terminal tractor
OEM; the Electric Vehicle Infrastructure Training Program, an industryled training program; the South Coast
Air Quality Management District, the
region’s air quality regulatory agency;
the Electric Power Research Institute
(EPRI); and Ramboll, a leader in sustainability engineering.
With a US$8 million grant from
the CEC, the US$16.8 million project
has three core components:
xx
installing sufficient electrical
infrastructure to support up to 39
charging stations in the future
xx
developing software to identify,
estimate, and forecast the costs
and requirements of establishing
zero-emissions terminals and
advanced energy operations
xx
installing the world’s first dc fastcharging system in a seaport
environment.
The project supports the first
phase of transition to a zero-emissions future at the Port’s largest
container terminal, Pier T, operated
by TTI.
PAVE Dynamic Energy
Forecasting Tool
The Port, Ramboll, port tenants, EPRI,
and SCE are developing a first-ever
flexible software tool known as the
Dynamic Energy Forecasting Tool
(DEFT). DEFT will allow the Port to
evaluate the impact of new electrical
equipment on the existing port electrical infrastructure and assess where
electrical and refueling infrastructure
upgrades may be required. DEFT will
also analyze how a combination of
energy efficiency measures, energy
storage, flexible charging times, and
other steps could help the Port and its
tenants avoid costly infrastructure
upgrades. The software will be adaptable and customizable to account for
changing assumptions unique to specific tenants and operators. The POLB
will make DEFT available to other
ports and terminal operators and
offer training to better guide planning
and infrastructure deployments for
others transitioning to zero emissions.
PAVE Infrastructure
The PAVE infrastructure will be
based at TTI’s Pier T facility, where
the Port estimates full electrification
of all vehicles and cargo-handling
equipment could require more than
85 MVA of instantaneous power
demand, excluding any load management technologies. As such, the
project incorporates an array of
technology and software solutions
to help the Port and its tenants intelligently and efficiently deploy zeroemissions freight vehicles and
equipment. Based on TTI’s current
and future plans for battery-electric
yard hostlers and forklifts, PAVE will
install electrical infrastructure and
“stubouts” supporting up to 39 charging stations at Pier T.
Fast Charging
Long Beach will be the world’s first
port to deploy and demonstrate a
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
9
TECHNOLOGY LEADERS
combined charging system/1.0-dc fastcharging system, i.e., the ChargePoint
Express Plus, for heavy-duty, zeroemissions cargo-handling equipment.
ChargePoint will provide four 240-kW
Express Plus dispensers and six 160-kW
power blocks, deployed so that each
dispenser can deliver up to 240 kW of
power simultaneously to four yard
hostlers equipped for dc fast charging.
The system incorporates a scalable
modular design capable of accommodating different power requirements,
charging standards, and site and capacity constraints. It is designed to last
more than 12 years to match the average yard hostler replacement cycle.
The Express Plus also uses dc power,
which means all ac-to-dc conversions
happen not on the hostler but within
the charging system, with much faster
charging times. Utilizing dc fast charging could ultimately help eliminate the
use of onboard equipment chargers,
which is expected to reduce the price
of the proposed electric yard hostlers
(currently twice as expensive as their
diesel counterparts) and potentially
increase the battery capacity of battery EVs and equipment. This would
be highly beneficial in rigorous port
duty cycles, which involve up to three
shifts per day with only a limited
time to recharge, and help promote
widespread deployment of zero-emissions technologies.
Energy Storage
ChargePoint’s fast-charging dispensers will be integrated with a
384-kWh/375-kW ac-connected energy storage system and controller. The
system uses Nissan Leaf battery technology. Known as grid-saver containerized energy storage (CES), the system
will support operation of the dc fastcharging system and enable the Port
and SCE to test energy storage as a
way to shave capacity requirements,
reduce energy costs, and increase reliability. Grid-saver CES incorporates
nickel manganese cobalt lithium-ion
battery technology and a compact,
high-efficiency inverter packaged in a
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I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
portable, climate-controlled 20-ft shipping container rated for seaside atmospheric conditions.
The PAVE project supports emerging connector standards, vehicle grid
standards, enhanced grid reliability
through real-time communication
with utilities, and opportunities for
Port terminals to participate in
demand-response programs. PAVE is
due to be completed by March 2022.
Microgrid Project
The Port’s Microgrid Project focuses
on energy resilience for critical infrastructure. With a US$5 million grant
from the CEC, the US$7.1 million
project involves developing a system
of on-site power generation, storage,
and controls, capable of isolating
from the grid and protecting terminal
operations against grid failures and
related losses and damages.
The project will be based at the
Port’s Joint Command and Control
Center (JCCC), a state-of-the-art facility that houses the Port’s Security
Division and Harbor Patrol operations. The JCCC also serves as an
interagency base for joint operations
with the Long Beach Police Department, Port of Los Angeles, U.S. Coast
Guard, U.S. Customs and Border Protection, and Marine Exchange of
Southern California, which tracks
arrivals and departures of all ships
from Port Hueneme to San Diego.
Schneider Electric will design,
engineer, construct, and commission
the microgrid. The project entails
installing a 300-kW solar carport, an
energy control center with microgrid
controls, and a 330-kW stationary
battery energy storage system. The
project includes a 250-kW microgridextending mobile battery energy
storage system that can be dispatched around the Port in lieu of
diesel generators in case of outages.
The JCCC was chosen because it is
a critical facility that the Port wants
to make more resilient, equipped
with skilled staff who are able to
operate the microgrid. Other technical
partners include SCE, the CEC, EPRI,
the U.S. Department of Energy
National Renewable Energy Laboratory (NREL), and the Advanced Power
and Energy Program of the University
of California, Irvine.
Paid on-the-job apprenticeships
during construction, as well as outreach to share project information
with ports and community colleges
throughout California, are part of the
workforce development component.
Outreach will include a “lessons
learned” document designed to support the replication and commercialization of the system at other seaports,
critical facilities, and operational centers of similar size. Partners include the
IBEW, LBCC, and California community
colleges. The Port’s microgrid is expected to be operational and ready for its
12-month demonstration by mid-2020.
The Commercialization
of the POLB Off-Road
Technology Project
The Commercialization of the POLB
Off-Road Technology (C-PORT) project
combines the demonstration of three
never-before tested battery-electric top
handlers and the head-to-head testing
of a hydrogen fuel-cell yard truck with
a battery-electric yard truck. A US$5.3
million CARB grant supports this
US$8.3 million demonstration.
Testing will be conducted at two
container terminals: SSA Marine at
Pier J and the LBCT’s Middle Harbor.
Partners include CARB, BYD, Kalmar,
TransPower, Taylor, the International
Longshore and Warehouse Union,
hydrogen provider Air Products, fuelcell provider Loop Energy Inc., truck
manufacturer China National Heavy
Duty Truck Group Company/Sinotruck
UQM, and engineering and data consultant Tetra Tech.
C-PORT Top Handlers
BYD’s battery-electric top handlers
featuring its highly stable battery will
be the first precommercial demonstration of an electrified top handler vehicle. The deployment also
represents a unique collaboration
with manufacturers working together
to streamline procurement and integration so that electric motors, power
drive systems, batteries, and other
specialized vehicle components are
built to precise and optimized capacities, torques, and other specifications.
If successful, the demonstration could
save an operator billions of dollars
because top handlers are critical and
unique pieces of equipment for container management; other ports and
goods movement industries could
realize this benefit as well.
C-PORT Battery-Electric
Yard Truck
TransPower will outfit the industry’s
popular Kalmar yard truck with the
same technology being tested in
the START project. TransPower’s
technology will also incorporate a
specially designed, heavy-duty, hightorque, electric fifth-wheel arm
capable of rapidly engaging and disengaging for high-capacity yard
truck operations (i.e., 40–50 engage/
disengage events per shift). The
truck will use a space-saving battery
pack customized for Kalmar’s yard
trucks, accommodating steps on
both sides of the tractor so that operators can climb into the cab more
easily and safely.
C-PORT Fuel-Cell Yard Truck
UQM technologies, in collaboration
with Loop Energy Inc., will demonstrate the first and only fuel-cell yard
truck in development. Utilizing
hydrogen fuel eliminates “range anxiety,” commonly associated with battery EVs, as well as the need for using
traditional fueling methods. Loop’s
precommercial eFlow hydrogen fuelcell system uses a proprietary design
that removes 30–40% of the capital
cost of traditional fuel cells. Loop
achieves this reduction through uniform oxygen dispersion across the
entire active area of the fuel cell,
thereby increasing power production
per unit of area by up to 40%. Loop’s
proton exchange membrane fuel
cells are the first to create uniform
current density across the cell, maximizing power production per unit
area, enhancing hydrogen-to-electricity conversion efficiency, and
increasing fuel-cell durability.
Project information will be integrated into the coursework at the
Port-sponsored Academy of Global
Logistics at Cabrillo High School in
Long Beach to support education and
workforce development for port technologies. Other education partners
include LBCC, the Center for International Trade and Transportation at
California State University, the City of
Long Beach, and community-based
environmental organization Green
Education, Inc. C-PORT is due to be
completed in 2020.
Port Community EV Blueprint
The Port Community EV Blueprint
(PCEVB) focuses on developing a comprehensive plan that identifies the
path toward zero emissions and charts
an economical, realistic approach to
EV planning for the Port and its supply
chain partners. The EV-specific road
map is also being developed as a
resource for other California ports.
The US$375,000 project is partly
funded with a US$200,000 CEC grant.
In addition to the CEC, SCE, and NREL,
project partners are the Pacific
Merchant Shipping Association, an
independent trade association representing terminal operators and ocean
carriers, and the City of Long Beach
Office of Sustainability. The process
will engage multiple business, utility,
and residential stakeholders.
The blueprint will cover all aspects
of zero-emissions planning and transformation, including concrete actions
and milestones for transitioning marine terminals, heavy-duty drayage
trucks, and visitor facilities (i.e., hotels,
commercial centers, and cruise ship
terminals) to emissions-free operations. In addition to evaluating equipment and vehicle fleet conversion, it
will address plans for energy manage-
ment and resilience in critical infrastructure and the broader implications
of moving to zero emissions for
adjacent commercial, industrial, and
residential zones, including disadvantaged communities.
The PCEVB is being developed to
help the Port and its partners navigate the complexities and time
frames for achieving the Port’s zeroemissions goals without incurring
excessive costs or disrupting economic activity. Specific tasks include
xx
analyzing technologies and systems that potentially offer the
best mix of economic, environmental, and technical performance specific to the region
xx
identifying factors, including the
existing wealth of vehicle usage
and driving pattern data, to
determine optimal locations for
EV charging infrastructure
xx
creating maps of proposed and
existing charging sites in the harbor district that also have accessibility to travel routes
xx
comparing and/or developing the
analytical tools, software applications, and data needed to improve
future planning activities
xx
assessing the effects of EV charging on utility rates and whether
special rates may be needed to
minimize financial impacts on
terminals, which are already significant energy consumers
xx
evaluating financial and business
models and collaborative strategies for creating EV-ready communities, including opportunities
for financing, grants, and incentives (public and private), allowing equipment owners and
manufacturers to accelerate the
deployment of EVs and charging
infrastructure
xx
developing outreach strategies,
including materials such as
journal articles, webinars, and
conference presentations, and
expanding support by education
(continued on page 59)
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
11
MAN WITH LIGHTBULB—©ISTOCKPHOTO.COM/Z_WEI,
ENERGY SET ON TRAY—©ISTOCKPHOTO.COM/ROCCOMONTOYA
By Eduardo Alejandro Martínez Ceseña,
Nicholas Good, Mathaios Panteli, Joseph Mutale,
and Pierluigi Mancarella
Flexibility
in Sustainable
Electricity Systems
Multivector and multisector nexus perspectives.
S ENVIRONMENTAL CONCERNS INCREASE, RESEARCHERS, POLICY MAKers, and the public in general are becoming more interested in options to
make energy more sustainable while at the same time ensuring that
energy systems are affordable, reliable, and resilient. This dynamic is
bringing about challenges across the world, as established energy systems (such as those in cities) must be enhanced to integrate large volumes of renewable
A
Digital Object Identifier 10.1109/MELE.2019.2908890
Date of publication: 11 June 2019
12
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
2325-5987/19©2019IEEE
this increased flexibility must be properly balanced within
the context of potential competition between services, e.g.,
tradeoffs when deciding whether to use water to generate
electricity or irrigate crops.
Smart and strategic use of flexibility from the demand
side and different energy technologies (e.g., from distributed devices, such as EHPs, to large technologies, such as
hydropower plants) will be critical for sustainable development based on both novel multivector and water–energy
nexus perspectives. Using examples of a smart district
and an integrated energy–water system, this article illustrates sophisticated applications of resource flexibility
that to go beyond power systems and take advantage of
joining with other energy vectors and sectors.
A Flexible Energy Future
Different Energy Futures
Figures 1–4 present different options for developing an
energy system that supplies a district with electricity and
heat. In a traditionally decoupled case (see Figure 1), dedicated systems supply customers with different energy
vectors, such as electricity and heat. This configuration
allows independent operation of each network and market, without the explicit consideration of other systems.
However, in this example, the demand side has a limited
ability to support the system, since customers would have
to change their behavior or be curtailed (which incurs discomfort) to reduce their energy demand.
Figure 2 illustrates the electricity-centered approach to
integrating intermittent RES in the electricity sector and
electrifying other energy vectors (e.g., heat). This approach
offers the advantage of allowing the RES generation to
produce heat, but the demand for heat and RES generation may be poorly correlated. This is the case in the United Kingdom, where the greatest heat demand occurs
during winter when energy generated from PV is low.
Once again, there is little flexibility for the demand side to
provide system support.
Electricity Network
Gas Network
energy sources (RES), while new or evolving systems (for
instance, in developing economies) must be planned to
manage the increasingly extreme conditions associated
with climate change. In these contexts, the flexibility to
intelligently use and invest in resources that go beyond
the power system (e.g., other energy vectors such as
heat, gas, or water dams) can be extremely valuable
from the perspective of sustainable development.
In cities, energy decarbonization and sustainable development are encouraging the electrification of transportation, heating, and other services, as well as the integration
of RES on a large scale. Take the United Kingdom as an
example. With the goal of decarbonizing transports by
2040, the sale of new gasoline and diesel cars will be
banned by 2032. Also, the U.K. government offers a sevenyear domestic renewable heat incentive for customers
who install electric heat pumps (EHPs) or other forms of
renewable heating, because heating corresponds to 40% of
domestic energy demand.
These solutions seem highly attractive at first glance,
because electricity produced with RES can be easily decarbonized and is becoming progressively cheaper. However,
accommodating the newly increasing demand for RES
generation in the electrical system is not an easy task.
Massive investments in electricity grid infrastructure (e.g.,
lines and substations) would be required to accommodate
the new power flows, as well as in generation, storage, and
other technologies that can provide reserve and active
control to balance the highly intermittent output of some
RES, such as wind and solar photovoltaic (PV). A more
effective approach would be to take advantage of the
existing assets. These resources would include district
heating and gas networks, as well as ongoing advances in
information and communication technologies (ICTs) and
automation, to allow the demand-side flexibility that is
now mostly enabled by multienergy technologies. This
multivector approach to demand-side flexibility empowers customers to use combinations of energy vectors (e.g.,
electricity, heat, and gas) to better meet their energy
needs, while also providing valuable capacity and reserve
support to the energy system.
The multivector approach to energy flexibility recognizes the attractiveness of using a suite of energy vectors and
networks to meet customer needs. Taking this vision a step
further, it may not make sense to constrain flexibility to the
energy sector in areas where little or no energy infrastructure has been installed, such as in rural areas or developing
economies. Instead, it is more valuable and sensible to consider the flexibility that investing in some infrastructures
can offer different sectors, such as hydropower plants that
merge the energy and water sectors and allow flexibility to
benefit other sectors (e.g., releasing water from the energy
sector to be used in the agricultural sector). Using resources
flexibly offers new opportunities to bring lighting, water,
food, and other valuable services to underserved customers
efficiently. However, in the so-called water–energy nexus,
Electricity
Demand
Heat
Demand
Boiler
Electricity
Heat
Gas
Figure 1. The traditionally decoupled energy services.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
13
With the goal of
decarbonizing
transports by 2040,
the sale of new
gasoline and diesel
cars will be banned
by 2032.
Installing energy storage, such as
batteries and thermal energy storage
(TES), may tackle some of these
issues. A battery can store the surplus
PV generated for later use or, as
shown in Figure 3, convert it to heat
and store it for later use. This strategy
could reduce electricity demand
because the heat stored in the TES
could reduce EHP operation later. This
system is more flexible than the two
presented previously, as the new multienergy system allows the intelligent
use of TES (through the use of ICT
and automation) to control electricity imports and exports
without affecting customers. For example, electricity
imports can be reduced by ramping down the EHP while
still meeting customer needs with the TES. The downside
to this approach is that it does not take advantage of the
available infrastructure, such as the gas network and boiler shown in Figure 1.
Other options, such as the one presented in Figure 4,
involve installing various low-carbon multienergy technologies, such as combined heat and power (CHP) boilers and
TES. Other technologies, such as PV and EHP, can also be
Electricity Network
Sun
Electricity
Demand
PV
Heat
Demand
EHP
Electricity
Heat
Insolation
Figure 2. Electrifying heat.
added. This type of system is highly
flexible, as there are multiple controllable options to meet the electricity
and heat demands. For example, if
grid electricity is inexpensive and
clean due to the availability of RES,
electricity imports can be increased by
ramping down the CHP boiler and
meeting heat demand with the TES
and boiler. It is also possible to reduce
the grid imports (e.g., to provide an
active network management) by
ramping up the CHP boiler and storing
surplus heat with the TES. This gives
customers new options not only to meet their energy
needs but to also reduce their energy bills, minimize their
carbon emissions, or pursue other objectives.
Integrated Multienergy Systems
The different energy futures presented in Figures 1–4
should be expected to lead to various mergers of energy
vectors. This coupling can impact the networks in place to
supply each vector, such as electricity, gas, and, where
applicable, district heating. Understanding these complex
effects is not trivial; it is necessary because the large-scale
electrification of heating and transports can lead to significant electricity network stress. Further, in a multienergy
future, actively managing stress in one network can lead
to issues in others, e.g., the use of CHP boilers to provide
electricity network support may cause issues in the heat
and gas networks. To visualize the effects, it is helpful to
map how different energy vectors are converted to useful
services or energy vectors (e.g., using generators and other
conversion technologies) and how energy vectors are distributed to customers using the available networks.
To illustrate this dynamic, consider the Manchester
district in the United Kingdom, presented in Figure 5.
The district comprises 26 buildings owned by the University of Manchester, some of which are connected to
the same electricity distribution (6.6 kV), district
Electricity Network
Electricity
Demand
PV
EHP
Electricity
TES
Heat
Figure 3. Electrifying heat and installing TES.
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I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
Heat
Demand
Insolation
CHP
Gas Network
Sun
Electricity Network
Boiler
Electricity
Figure 4. Installing CHP and TES.
Electricity
Demand
TES
Heat
Heat
Demand
Gas
Electricity
Heat
Gas
Figure 5. The Manchester multienergy district.
heating, and gas networks. The district has an annual
demand of 28 GWh (6-MW peak) of electricity and
18 GWh (12-MW peak) of heat. The current, baseline
annual energy costs and carbon emissions are 3.1 £M
and 19.1 ktCO2, respectively. Different options for meeting the district’s electricity and heat needs are mapped
using Sankey diagrams in Figures 6–8. The district and
various options to make it more flexible were investigated in the District Information Modeling and Management for Energy Reduction (DIMMER) research project
(Patti et al. 2015).
Figure 6 depicts the traditionally decoupled energy
system used as a baseline to represent current conditions. In this case, electricity is delivered to customers
using the electricity networks, while heat is produced
with local boilers or larger boilers connected to a district
heating network, which takes fuel from the gas network.
In the electrified future presented in Figure 7, the gas
network is no longer used; instead, significantly more
electricity is taken from the grid (compared with the
baseline in Figure 6) to supply EHPs. The electricity grid
would require additional capacity to reliably meet the
new demand. In this context, the reliability of the electricity system becomes more critical, since outages
would impact both electricity and heat supplies and can
make customers vulnerable, especially during periods of
harsh ambient conditions. In the United Kingdom, energy system stress and the effects of contingencies on the
network and customers are the highest during the coldest winter days.
Figure 8 presents a multienergy future in which the
electricity grid, local EHPs, and district CHP boilers meet
customer needs. The additional demand on the electricity
grid is modest compared with the case presented in Figure 7, and the system still utilizes some of the gas network’s capacity. In this case, future demand growth can
still be met with low-carbon technologies (e.g., CHP
Grid
Electricity
Electricity
Network
Electricity
Local Gas
Boiler
Heat
Heat
Network
Gas Network
Heat Losses
District-Level
Conversion Losses
Gas Boiler
Gas Losses
Figure 6. The Sankey diagram: decoupled energy services.
Ambient Heat
Local EHP
Heat
Heat
Network
Grid
Electricity
Electricity
Network
Heat Losses
DistrictLevel EHP Electricity
Figure 7. The Sankey diagram: multienergy system.
boilers), which may not require network reinforcements.
The system also is more flexible to withstanding contingencies in the electricity or gas networks. If the electricity
supply is interrupted, local heat and electricity can be produced with the CHP boilers, while the EHPs can be used to
supply some customers if the supply of gas is interrupted.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
15
Ambient Heat
Local EHP
Gas
Network
DistrictLevel CHP
Grid
Electricity
Electricity
Network
The multienergy future offers greater flexibility, the use
of existing assets, and less network stress than the electrified future. However, this energy future is also the most
complex because the traditionally decoupled energy systems (e.g., electricity, heat, and gas) would operate as a
single integrated system. As a result, the energy sector
would no longer comprise independent systems that provide electricity, heat, gas, and other energy vectors.
Instead, the energy system will comprise integrated assets
that use combinations of multiple available energy vectors
to meet customers’ needs for lighting, heating, cooking,
and other services.
Even though the examples from Figures 1–8 are for
multivector applications of flexibility in smart cities, it
is possible to infer some key ideas that are applicable
to the energy nexus in rural areas and developing
economies. First, more and potentially better options
to meet customer needs become available when we
consider the coupling of multiple sectors (the energy
vectors in the examples). Flexibility makes the system
more resilient to extreme events caused by climate
change (network contingencies in the examples). New
tradeoffs can arise as limited resources are used to
provide different resources, e.g., water can be used to
generate electricity or for irrigation. A demand
response could be used to reduce energy bills or carbon emissions in the examples.
Heat
Heat
Network
Heat Losses
Conversion Losses
Electricity
Figure 8. The Sankey diagram: electrifying heat.
TABLE 1. The installed boiler, PV, EHP,
and CHP capacities in each case.
Aggregated Installed Capacity
Throughout the District (kW)
Case
Boiler
PV
EHP
CHP
Baseline
24,000
93
0
0
Conservative
24,000
1,068
310
260
Modest
24,000
2,250
1,715
1,925
Extreme
24,000
3,410
2,650
2,700
The Value of Multivector
Flexibility
TABLE 2. The performance of the Manchester district
subject to the considered cases and BAU practices.
Investing in Multienergy Assets
Baseline
Conservative Modest
Extreme
Annual economic savings*
0%
9.06%
12.22%
14.83%
Annual carbon savings*
0%
10.14%
19.94%
26.90%
Peak electrical demand reduction*
0%
4.67%
2.20%
2.37%
Peak heat demand reduction*
0%
15.50%
52.80%
72.51%
To illustrate the value of flexibility attributable to multienergy
assets, consider the Manchester
district under traditionally decoupled baseline conditions and
business as usual (BAU) operation
(i.e., the heat-following mode). In
addition to the baseline case,
which represents the system’s
*: compared with the baseline.
TABLE 3. The performance of the Manchester district subject to the considered cases:
BAU versus smart practices.
Conservative
Extreme
BAU
Smart
BAU
Smart
BAU
Smart
Annual economic savings*
9.06%
9.54%
12.22%
21.44%
14.83%
28.43%
Annual carbon savings*
10.14%
10.28%
19.94%
27.00%
26.90%
38.07%
Peak heat demand reduction*
4.67%
12.63%
2.20%
41.03%
2.37%
49.38%
Peak electrical demand reduction*
15.50%
28.48%
52.80%
84.88%
72.51%
95.07%
*: compared with the baseline.
16
Modest
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
Using resources
flexibly offers new
opportunities to
bring lighting, water,
food, and other
valuable services
to underserved
customers
efficiently.
shows that using a smart operation
for the district can improve its performance, especially in extreme cases
where more controllable resources
are available.
The study is taken one step further
by optimizing the operation of the district based on a wide range of different
objectives, including minimizing of
costs and emissions and maximizing
benefits from trading active network
management, energy, reserve, and
other services in relevant markets. See
the suite of results in terms of the net
present cost (NPC) in Figure 9. This
smart operation of the district is more
in line with the premise that an energy
system should not be operated to provide energy vectors
(e.g., electricity and gas), but instead use combinations of
available energy vectors to meet customers’ needs for lighting, heating, and other services. The results show that it is
possible to achieve different environmental and economic
savings by customizing the district’s operation. This
20
CO2 (ktCO2)
current conditions, three different
cases are considered: conservative,
modest, and extreme. In the conservative case, in addition to installing
PV, EHP, and CHP devices, Manchester University invests in awareness
campaigns to encourage switching
lights and computers off when they
are not in use, as well as modest
interventions in double-glazed steel
windows and waterproof roof covers. In the modest case, the university makes additional investments in
energy devices and efficiency measures. In the extreme case, relatively
large investments in energy efficiency measures are made, which are
coupled with a significant installation of energy infrastructure. The total PV, EHP, and CHP capacities associated with each case are presented in Table 1, and the
district’s relevant economic and environmental performance is presented in Table 2.
In these cases, following BAU practices, the multienergy infrastructure operates in the heat-following mode.
These practices do not take advantage of the energy sector’s variable needs or the district’s potential to operate in
a smart manner. Accordingly, it is reasonable to assume
that the benefits reported in Table 2 correspond mainly to
the multienergy assets’ value of flexibility.
Smarter Operation
It is possible to pursue different objectives, such as
achieving economic and carbon savings, by optimizing
the set points of the controllable devices within the district. Smart operation, in which the district is operated
considering variable price signals that reflect the costs of
the energy supply, network/system operation, and taxes,
allows customers to minimize their energy bills and carbon emissions and could also permit them to trade
demand-side flexibility in different markets. This type of
operation can be substantially more attractive than traditional BAU practices, as shown in Table 3. The study
18
16
14
12
10
2
2.2
2.4
2.6
2.8
NPC (M£)
3
3.2
3.4
Baseline (BAU)
Baseline (Smart)
Conservative (BAU)
Modest (BAU)
Extreme (BAU)
Conservative (Smart)
Modest (Smart)
Extreme (Smart)
Figure 9. The performance of the Manchester district under different
conditions.
TABLE 4. The value of flexibility associated with assets and smart operation.
Economic Savings (%*)
Conservative
Modest
Extreme
Benefit Attributed To
Minimum
Maximum
Minimum
Maximum
Minimum
Maximum
Assets
10.17
9.06
20.02
12.22
27.06
14.83
Smart operation
0.31
0.47
8.61
9.98
13.1
15.33
Total
10.48
9.54
28.63
22.20
40.16
30.16
*: compared with the baseline energy costs.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
17
A significant volume
of energy may be
generated and
consumed locally,
instead of produced
by large generators
and then
transported.
information is particularly valuable in an
uncertain future where RES generation,
asset costs, and other assumed parameters are different from what is forecast.
For example, carbon targets can still be
met by changing the operation of the
Manchester district without investing in
additional assets, even if the future differs
from the forecast.
It is important to emphasize that
smart operation provides flexibility and
can be as valuable as, or more valuable
than, the one provided by the asset. This
can be deduced by comparing the
extreme (BAU) and conservative (smart)
cases in Figure 9. The latter, which uses fewer assets,
can outperform the former, which does not take advantage of smart operation. This is further demonstrated in
Table 4, which takes the maximum and minimum values from Figure 9. The table shows that most benefits
in the extreme case can be attributed to smart operation
of the assets. This is an important result because it
Beyond the Demand Side
Impacts on the Energy System
As flexibility increases in the energy
sector, mostly due to introducing
multienergy technologies at the
demand side, smart-community
multienergy systems such as the Manchester district will
take some business away from current actors. That is, a
significant volume of energy may be generated and consumed locally, instead of produced by large generators
and then transported by the transmission system operator (TSO) and multiple distribution network operators
(DNOs). This new system operation may be beneficial if it
Contractor
Network Operator
System Operator
demonstrates that it is not enough
to foresee a sustainable multivector future by in stalling RES and
multienergy technologies; most of
the value offered by these technologies will materialize only if the
assets use smart operation also.
Contractor
TSO
Policy
Implementer
Network Operator
DNO
Tax Raiser
Demand-Side
Flexibility
Government
Smart Customers
Trader
DNO
Other Retailer
Service Provider
Gas DNO
Trader
Trader
Gas Shipper
Electricity Producer
Energy
Figure 10. The value flow map.
18
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
Cash
Information
Contractor
Gas DNO
TSO
DNO
Government
Electricity Producer
District
Electricity Generation (MW)
Change in Operational Revenue (k£/Year)
displaces dirty and expensive electricity generation units.
payments. This would have a negative impact in the form
But it can also be harmful if, for instance, it reduces the
of lost revenue (compared with the BAU case) for electricity
revenue of network operators who are responsible for conproducers, the government, and network operators, i.e.,
necting the multienergy resources and enabling the busireduced distribution and transmission use of system chargness of smart districts or if it makes the business case for
es (DUoS and TUoS, respectively). As discussed previously,
generating new firms.
some of these effects can be considered acceptable if, for
To understand the effects that demand-side flexibility
example, carbon-intensive generators are driven out of
(e.g., from the Manchester district) can have, it is convebusiness. However, the reduced revenue may not be acceptnient to map the interactions within the energy sector
able, especially considering that the integration of different
(see Figure 10). Developed using value-flow approaches,
distributed multienergy technologies within the district
the map tracks the energy, cash, and information exchangmay lead to increased network stress and costs.
es between different actors in the
energy sector. These exchanges are
based on
800
1) the physical characteristics of
Wholesale Electricity
the system (e.g., electricity is
600
Imbalance
generated by producers and
Capacity
400
travels through the transmisElectricity DUoS
sion and distribution networks
Electricity TUoS
200
to reach customers)
BSUoS
2) the regulatory framework (e.g.,
0
ESO and VAT
customers pay retailers who
Whole Gas
then pay DNOs, the TSO, and
–200
Gas DUoS
other actors)
O and M
–400
3) emerging business cases (e.g.,
Net
contractors may provide opera–600
tion and maintenance to the
multienergy infrastructure within the smart district).
A main advantage of the valueflow mapping approach is that it
facilitates quantifying the effects of
district optimization on different
revenue flows, for customers with- Figure 11. The business case analysis. BSUoS: balancing services use of system; ESO: environin the district and other actors (see mental and social obligation; VAT: value-added tax.
the quantification of the change of
revenue for selected actors in Figure 11). In this context, the district
250
manager, retailer, aggregators, or
other actors that can represent cus200
tomers in different energy markets
no longer focus only on the provi150
sion of energy vectors but, instead,
concentrate on providing services.
100
These services can be tracked to
the actors who would normally
50
provide them, so that the impact of
the smart district on the business
0
of such actors can be assessed.
1
6
11
16
21
In this example, smart operation
Time
(h)
of the Manchester district in the
extreme case brings about signifiConventional (BAU)
Hydro (BAU)
PV (BAU)
Conventional (Smart)
Hydro (Smart)
PV (Smart)
cant benefits for customers. It takes
advantage of price arbitrage in the
wholesale energy market and Figure 12. The conventional, hydropower, and PV-generation profiles subject to BAU
reduces network charges and tax and smart operation.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
19
From the perspective of the energy
system and different actors, this information is critical for understanding
potential issues regarding the introduction of demand-side flexibility. For
example, based on the study presented
in Figure 11, it may be convenient to
introduce active network-management services, adjust network charges,
or introduce other mechanisms to
allow network operators to support
their business as well as the business
of the smart district.
A multisector energy
nexus approach is
better suited for
providing food,
water, lighting, and
other critical
services for people
in rural communities
and developing
economies.
production of clean power. In this
example, peak conventional generation
and total PV generation in the smart
cases are 15% lower and 20% higher,
respectively, than in the BAU case.
This increased power system flexibility can bring attractive benefits to
the energy sector by reducing electricity costs and carbon emissions and by
displacing conventional peaking generation. That is, the system’s flexibility
would allow it to meet customers’
needs for affordable and sustainable
electricity. However, the added flexibilThe Energy Nexus
ity could, instead, be used to maintain
The multivector application of energy
the affordability and sustainability of
system flexibility can meet customers’
current energy services while reducing
needs in cities that have established
the use of hydropower. The result
networks. Taking a step further, a mulwould be reduced future investments
tisector energy nexus approach is better suited for providing
in hydropower capacity, lower water demand to generate
food, water, lighting, and other critical services for people in
electricity, and more water available for irrigation, drinking,
rural communities and developing economies. To illustrate
and other uses. Also, it could potentially avoid the conthis, consider the flexible use of hydropower plants to balstruction of costly carbon-intensive infrastructure in differance intermittent RES (e.g., PV power) by storing surplus
ent sectors.
solar power as water. As shown in Figure 12, which is based
Based on such a water–energy nexus vision, the energy
on the IEEE 14-bus test network, smart operation of the
system is treated as part of a wider suite of interrelated
hydropower plant can greatly reduce the peak conventional
sectors. In this context, flexibility is no longer constrained
generation capacity required by the system and increase the
to the use of energy vectors to meet customers’ needs; it
also optimizes the use of water,
food, and other resources. To investigate this advanced use of flexibiliInvestment
Energy Nexus Simulator
ty, novel frameworks, such as the
Scenario
one presented in Figure 13, have
Water
been proposed. They assess interacClimate
Water Model
Allocation
Scenarios
tions among different sectors and
shed light on the smart use of flexiInvestment
bility and the infrastructure deployProfiles
ment that would be the most
beneficial for different sectors subEnergy Mix
Energy Model
ject to an uncertain future.
Energy Demand
Nexus tools can bring specialized models of different sectors
together in an iterative fashion to
produce a wide range of strategies
for investing in electrification,
Other Models
multienergy technologies, and
other infrastructures needed to
meet customers’ needs. The tools
are particularly attractive for highly uncertain scenarios in which
Environmental,
the use of flexibility (from differAssessment
Economic, and
Model
ent energy vectors and various
Other Criteria
sectors) is critical, such as for
developing future energy–water–
food systems that are resilient to
Figure 13. The energy nexus planning and assessment framework.
climate change.
20
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
Even with the sophisticated energy nexus tools, the
identified strategies are seldom perfect and will have
several positive and negative impacts in different sectors
(i.e., tradeoffs). Assessing the tradeoffs between different
sectors is not an easy task (e.g., comparing the value of
minimizing the risks of a power outage against the risks
of a flood) and will require lengthy negotiations among
planners, policy makers, and relevant actors in each
sector. Regardless, the identified strategies could be significantly better than those identified by addressing a
single sector.
Conclusions
The United Nations sustainable development goals are
increasingly motivating the flexible use of different
resources from various vectors and sectors to meet
customer needs. A multivector approach to demandside flexibility will be particularly valuable in cities that
already have a significant energy infrastructure. In
these cases, integrating multienergy technologies, such
as cogeneration, batteries, and thermal storage, would
make the energy system significantly more flexible if it
is enabled with ICT, automation, and smart control.
Large-scale deployment of these resources may lead to
a new role for flexibility in operating the energy sector,
as its focus will no longer be on providing electricity,
gas, and other vectors. Instead, it will primarily use
combinations of energy vectors to accomodate customers’ services.
The services that the smart use of flexibility can provide do not have to be constrained to energy, particularly
in rural areas or developing economies where little or no
energy infrastructure is in place. Instead, a more holistic
multisector nexus approach can be used to enable the use
of flexibility to better provide energy, water, food, and
other key services.
Although the multivector and nexus approaches are
more complex than the traditionally decoupled ones for
energy planning, they provide attractive options to better tackle large challenges, such as climate change and
the large-scale integration of RES. In this context, it is
critical to rethink the role of flexibility as a means to
intelligently take advantage of the resources and strategic investments available and effectively provide the
required services.
Acknowledgments
We would like to acknowledge the following groups for
financial support as part of their projects: European Commission, for “DIMMER: District Information Modeling and
Management for Energy Reductions” under grant FP7
609084; the U.K. Engineering and Physical Sciences
Research Council, for “MY-STORE: Multi-Energy StorageSocial, Techno-Economic, Regulatory and Environmental Assessment under Uncertainty” under grant EP/
N001974/1; and the U.K. Economic and Social Research
Council, for “FutureDAMS: Design and Assessment of
Water-Energy-Food-Environment Mega-Systems” under
grant ES/P011373/1.
For Further Reading
E. A. Martínez Ceseña and P. Mancarella, “Energy systems
integration in smart districts: Robust optimisation of multienergy flows in integrated electricity, heat and gas networks,”
IEEE Trans. Smart Grid, vol. 10, no. 1, pp. 1122–1131, 2019.
X. Liu and P. Mancarella, “Modelling, assessment and Sankey diagrams of integrated electricity-heat-gas networks in
multi-vector district energy systems,” Appl. Energy, vol. 167,
pp. 336–352, Apr. 2016.
N. Good, E. A. Martínez Ceseña, C. Heltorp, and P. Mancarella, “A transactive energy modelling and assessment
framework for demand response business cases in smart distributed multi-energy systems,” Energy. [Online]. Available:
https://www-sciencedirect-com.manchester.idm.oclc.org/
science/article/pii/S0360544218303177
E. A. Martínez Ceseña, N. Good, A. L. A. Syrri, and P. Mancarella, “Techno-economic and business case assessment of
multi-energy microgrids with co-optimization of energy,
reserve and reliability services,” Appl. Energy, vol. 210, pp. 896–
913, Jan. 2018.
N. Good, E. A. Martínez Ceseña, and P. Mancarella, “Ten
questions concerning smart districts,” Build. Environ., vol. 116,
pp. 362–376, June 2017.
E. A. Martínez Ceseña, T. Capuder, and P. Mancarella, “Flexible distributed multi-energy generation system expansion
planning under uncertainty,” IEEE Trans. Smart Grid, vol. 7, no.
1, pp. 348–357, 2016.
N. Good, E. A. Martínez Ceseña, L. Zhang, and P. Mancarella, “Techno-economic assessment and business case modelling of low carbon technologies in distributed multi-energy
systems,” Appl. Energy, vol. 167, pp. 158–172, Apr. 2016.
Y. Zhou, M. Panteli, R. Moreno, and P. Mancarella, “System-level assessment of reliability and resilience provision
from microgrids,” Appl. Energy, vol. 230, pp. 374–392, Nov.
2018.
E. Patti, A. Ronzino, A. Osello, V. Verda, A. Acquaviva, and
E. Macii, “District information modeling and energy management,” IT Professional, vol. 17, no. 6, pp. 28-34, Nov./Dec.
2015.
Biographies
Eduardo Alejandro Martínez Ceseña (alex.martinezcesena@
manchester.ac.uk) is with the University of Manchester,
United Kingdom.
Nicholas Good ([email protected]) is with
Upside Energy Ltd, Manchester, United Kingdom, and the
University of Manchester, United Kingdom.
Mathaios Panteli (mathaios.panteli@manchester.
ac.uk) is with the University of Manchester, United
Kingdom.
Joseph Mutale ([email protected]) is with the
University of Manchester, United Kingdom.
Pierluigi Mancarella (pierluigi.mancarella@unimelb
.edu.au) is with the University of Melbourne, Australia,
and the University of Manchester, United Kingdom.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
21
By Jairo Quirós-Tortós, Luis Victor-Gallardo,
and Luis (Nando) Ochoa
Electric Vehicles
in Latin America
Slowly but surely toward a clean transport.
HE NUMBER OF LIGHT-DUTY ELECTRIC
vehicles (EVs) in Latin America—from plug-in
hybrid to fully electric—is expected to
increase during the next decade as a result of
multiple incentives that promote their adoption combined with the increasing cost effectiveness of the
technology. Latin American countries are slowly but surely
T
Digital Object Identifier 10.1109/MELE.2019.2908791
Date of publication: 11 June 2019
22
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
moving toward the electrification of the transport sector, trying to harness the corresponding environmental, health, and
economic benefits, particularly when coupled with a low-carbon electricity-generation portfolio, such as many of those in
the region. However, before the region sees EVs being adopted
at levels already realized in countries in Europe and Asia, and
in the United States, several challenges need to be addressed.
A number of factors limit the progress of EVs in Latin
America, including
x upfront costs that are too high for developing
countries
x lack of effective subsidies for EVs that reduce the purchasing cost
x insufficient charging infrastructure
x subsidized fossil fuels
x a lack of vehicle fuel-efficiency standards
x bidding processes that prioritize least-cost options
and disqualify cleaner technologies with higher upfront costs.
To overcome these barriers, governments need to
strengthen financial incentives and standards
favoring clean technologies, expand programs for electrifying high-use vehicles,
develop electric mobility strategies
and goals, and create public-private partnerships.
MAP—©ISTOCKPHOTO.COM/BGBLUE,
CAR—IMAGE LICENSED BY INGRAM PUBLISHING
2325-5987/19©2019IEEE
TABLE 1. Development indicators for Latin America.
Country
GDP (Millions in US$)
GDP Growth (%)
Population
Unemployment (%
of Total Labor Force)
Argentina
637.59
−2.6
44,271,041
8.35
Bolivia
37.51
4.3
11,051,600
3.23
Brazil
2,055.50
1.4
209,288,278
12.83
Chile
277.08
4
18,054,726
6.96
Colombia
309.19
2.8
49,065,615
8.87
Costa Rica
57.06
3.3
4,905,769
—
Ecuador
103.06
1.1
16,624,858
3.83
El Salvador
24.81
2.5
6,377,853
4.38
Guatemala
75.62
2.8
16,913,503
—
Honduras
22.98
3.5
9,265,067
—
Mexico
1,149.92
2.2
129,163,276
3.42
Nicaragua
13.81
−4
6,217,581
—
Panama
61.84
4.6
4,098,587
3.90
Paraguay
29.73
4.4
6,811,297
4.61
Peru
211.39
4.1
32,165,485
—
Uruguay
56.16
2
3,456,750
7.89
Venezuela
—
—
31,977,065
—
Constructed with data from the World Economic Forum of the IMF for October 2018.
In this article, we provide an overview of the different incentives in place in Latin America and discuss
the effectiveness of each given the international experience. We also discuss challenges associated with the
deployment of public charging stations, list the number
of public charging stations available in Latin America,
and describe a simplified methodology developed in
Costa Rica for defining the location of fast-charging
stations. We conclude by presenting the results of an
economic assessment of the technology to understand
the reasons behind the current low number of EVs in
Latin America and, more importantly, to highlight key
actions needed from policy makers to promote a greater EV adoption.
Latin America Today
Latin America refers to a group of 13 dependencies and 20
countries. Due to data availability, however, in this article
we discuss the situation in 17 of them: Argentina, Bolivia,
Brazil, Chile, Colombia, Costa Rica, Ecuador, El Salvador,
Guatemala, Honduras, Mexico, Nicaragua, Panama, Paraguay, Peru, Uruguay, and Venezuela. The region extends
from the northern border of Mexico to the southern tip of
South America, with the total population estimated at 600
million inhabitants living in a total area of approximately
7,412,003 mi2 (19,197,000 km2).
According to the International Monetary Fund (IMF),
in 2018 Latin America had a gross domestic product
(GDP) growth of approximately 2.28% (excluding Venezuela) (see Table 1). In the same year, the region experienced a population growth of approximately 6 million
while facing an unemployment rate growth of close to
0.6%, which, in turn, led to an average unemployment
rate of 6.2%. Over the past decade, the number of people
living in metropolitan areas increased by 10% in the
region, resulting in 80% of the Latin American population
residing in urban areas. During the same decade, the
number of light-duty internal combustion (IC) vehicles
grew in these areas by approximately 40%, which has
caused congestion issues due to the relatively poor
30-year-old infrastructure (see the 2016 report from the
Inter-American Development Bank).
Aiming to reduce the environmental impact of this growing urbanization and uptake of light-duty IC vehicles, multiple countries in the region set aggressive environmental
targets during the 2015 United Nations Climate Change
Conference. Given that carbon dioxide emissions in the
Latin American transport sector represent approximately
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
23
45% of the total, these goals usually translate into the electrification of the transportation sector (both private and
public fleets).
The adoption of EVs will help decarbonize the economy
of the region, and Latin America already has one of the
cleanest electricity-generation portfolios in the world as a
result of its high production of hydroelectric power and the
growing deployment of wind and solar power plants.
According to International Energy Agency (IEA) data (electricity information for 2016), the use of renewables, including hydroelectric power, in the electricity mix is, on
average, 41.3%, with Brazil, Costa Rica, Paraguay, and Uruguay producing more than 70% from clean technologies
(see Figure 1). If Latin America continues increasing the use
Honduras
Nicaragua
49.1% 50.9%
Mexico
57.1%
42.9%
15.3%
Costa Rica
84.7%
Colombia
1.8%
Guatemala
98.2%
34.1%
65.9%
Venezuela
40.2%
59.8%
39.9%
41.9%
60.1%
33.4%
58.1%
66.6%
EI Salvador
Panama
19.7%
39.8%
60.2%
80.4%
49.7% 50.3%
Ecuador
Brazil
Peru
21.9%
78.1%
Latin America
Bolivia
100%
41.3%
Paraguay
58.7%
Hydro, Solar,
Wind, Biofuels,
and Geothermal
Other Sources
43.3%
56.7%
Chile
3.4%
27.2%
72.8%
96.7%
Uruguay
Argentina
Figure 1. Renewable energy use per country in Latin America, created with data from the IEA. hydro: hydroelectric.
24
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
of renewables, it will be in a strong position to ensure that
the demand resulting from the electrification of transport
is supplied by low carbon generation, reducing overall
emissions. However, the region faces three key challenges:
lack of incentives, insufficient charging infrastructure, and
the low cost effectiveness of EVs, which we discuss in the
following sections.
What Incentives Are in Place?
and owners of IC vehicles pay fees or tax increases. An
advantage of this approach is that it makes it easier for
countries to sustain financial incentives for EVs during
longer periods.
When defining the type of financial support in each
country, governments must take into account the corresponding tax structure to avoid significant fiscal impacts
(as an illustration, see the tax structure of some countries
in Latin America as detailed in Table 2). Because valueadded and import taxes of IC vehicles are generally an
important share of the tax structure (they represent, on
average, approximately 65% of the total tax in the region),
The number of EVs in Latin America is growing, but it has
not reached a five-digit figure as of yet. Aiming to meet this
milestone and reduce corresponding greenhouse-gas emissions, some Latin American countries have put in place a number of
financial (e.g., reducing taxes) and
TABLE 2. The tax structure for vehicles
nonfinancial (e.g., dedicated parking
in some Latin American countries (%).
spaces) incentives, tighter fuel-econImport
Value
omy standards, and electric-mobility
Tax
Duty
Added
strategies. The following sections
Argentina
IC
0.5
21
describe the common incentives in
place in the region and list the counEV
2
10.5
tries that have adopted them.
Brazil
IC
35
18
Financial Incentives
Financial incentives are generally
the most direct option for promoting
the uptake of EVs in Latin America
(and worldwide). Therefore, governments in the region are making
efforts to provide economic support
that lowers the current high retail
price (one of the main barriers to
EVs). In general, governments are
cutting down the cost of EVs through
rebates and reduced taxes. From a
practical perspective, both options
are effective in achieving a lower EV
cost. Rebates, however, are more
beneficial when a light vehicle tax
structure is in place.
Although governments in Latin
America are promoting the uptake
of EVs through financial incentives,
they face a challenge when offering tax exemptions or rebates, as
vehicle taxes usually represent an
important income stream. Additionally, this financial support may be
seen as socially regressive because
early EV adopters tend to belong to
the high-income population. Thus, a
less controversial approach—used
in Chile, for instance—is to implement revenue-neutral financial
incentives for EVs. Here, owners of
EVs receive rebates or tax reductions,
Chile
Colombia
Costa Rica
Ecuador
El Salvador
Honduras
Mexico
Panama
Paraguay
Peru
Uruguay
Other
Total
(Arithmetic Sum)
8.5
30
8.5
21
25
78
EV
0
18
20
38
IC
6
19
0
25
EV
6
19
0
25
IC
35
19
8
62
EV
0
0
0
0
IC
1
13
38.5
52.5
EV
0
0
0
0
IC
15
14
15
44
EV
0
0
0
0
IC
25
13
6
44
EV
25
13
6
44
IC
10
15
30
55
EV
10
15
30
55
IC
0
16
4
20
EV
0
16
0
16
IC
0
7
25
32
EV
0
7
5
12
IC
15
10
0.5
25.5
EV
0
10
0.5
10.5
IC
9
16
37
62
EV
9
16
37
62
IC
23
22
39.5
84.5
EV
0
22
10.75
32.75
Constructed with data from the 2016 report from the Inter-American Development Bank and available information per country.
Some values are calculated as the average.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
25
Financial incentives
are generally the
most direct option
for promoting the
uptake of EVs in
Latin America
(and worldwide).
Latin American countries tend to promote a reduction of or exemption
from these taxes for EVs. Costa Rica
and Ecuador offer an exemption from
the value-added tax for EVs, and
Colombia set a partial reduction. Multiple countries—including Brazil,
Colombia, Costa Rica, and Mexico—
have adopted a full exemption from
the import tax, and Argentina set a
partial reduction to this tax.
Governments can also incentivize
the adoption of EVs through the
deployment of financial incentives
that reduce the yearly costs of owning and/or using an EV.
The typical options are reductions in ownership or circulation annual taxes (e.g., Colombia and Costa Rica), tolls (e.g.,
Colombia, Costa Rica, and Mexico), parking fees, insurance,
subsidies for electricity (e.g., Ecuador and Mexico), and so
on. Although these incentives help, they do not reduce the
up-front cost of EVs (they reduce costs over a multiple-year
time span); this explains why governments put more effort
into reducing the purchasing cost of EVs.
(Colombia), San José (Costa Rica),
México D. F. (México), and São Paulo
(Brazil), enacted license-plate-based
restrictions on the use of cars during
certain weekdays and peak hours. This
policy, however, led to an incremental
increase in car ownership and use levels because some households bought
a second car (usually an old car with
high emission levels). In this context,
exempting EVs from license-platebased restrictions is probably one of
the best options for Latin American
cities to provide nonfinancial incentives for EV adoption. Colombia and Costa Rica have implemented this type of policy to promote the adoption of
EV technology.
The third nonfinancial incentive is to allow EVs to use
a number of dedicated parking spaces in public parking
lots. This practice, successfully implemented in Colombia,
Costa Rica, and Mexico, is likely to be a good policy for promoting EVs, because it will affect the parking availability
of IC vehicles only marginally while providing a valuable
benefit for EVs.
Nonfinancial Incentives
Financial incentives are the most effective way to promote
EVs; however, nonfinancial incentives are also important
in the transition toward a clean transport. Although these
incentives are country specific, or even city specific, the
following are common:
1) allowing EVs to use bus-only lanes
2) offering a waiver on driving restrictions (e.g., licenseplate-based restrictions) for EVs
3) providing dedicated EV parking spaces.
Allowing EV users to use bus-only lanes can have benefits; however, this practice may lead to poorer public transportation services, which, in turn, may result in more
people leaving the public transportation system and, thus,
be a detriment to urban transportation sustainability. Consequently, although this practice is used in European cities, it might not be a suitable policy in Latin American
cities, especially if public transportation is to be promoted.
To mitigate environmental and/or congestion problems,
governments in Latin American cities, such as Bogotá
Where Does Latin America Stand on
Public Charging Infrastructure?
Public charging infrastructure is important to ensure that
EV users can travel distances longer than what is typical
for commercially available EVs in the region [approximately 124 mi (200 km) with a full battery]. The deployment of
this infrastructure—more specifically, level 2 (semirapid)
and level 3 (fast) charging stations—has already started
across the region. Table 3 illustrates how quickly these
charging stations can reach 80% capacity for two common
battery sizes.
To help EV users locate public chargers, the private and
public sectors use different online platforms (e.g., https://
www.plugshare.com/, https://www.electromaps.com/puntosde-recarga/mapa, and https://movilidad.ute.com.uy/carga
.html). These online platforms inform EV users about the
availability of charging stations and report the connector
type of the charger, which is critical so that users can
check compatibility with their EV. Figure 2 shows the maximum number of level 2 and level 3
chargers (regardless of connector
type) reported by these online platTABLE 3. The estimated time required to charge a battery to
80% capacity.
forms per country (obtained from
20–26 January 2019). There are
Charger Power
approximately 628 level 2 chargers
Battery
(90.5%) and 66 level 3 chargers
Level 2 (Semirapid) 3.7–22 kW
Level 3 (Fast) 22–200 kW
Capacity
(9.5%) in Latin America.
11 kW
22 kW
50 kW
100 kW
150 kW
(kWh)
Although these are estimated
values, they allow us to compare
28
~2 hr
~1 hr
~27 min
~14 min
~9 min
the current situation of public fast
40
~3 hr
~1.5 hr
~38 min
~20 min
~13 min
chargers in Latin America with
26
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
The up-front cost of
EVs is usually higher
than that of IC
vehicles; however,
their yearly operation
and maintenance
costs are typically
lower.
respect to the rest of the world, based
on the Global EV Outlook 2018 of the
IEA. According to this report, there
were 82,880 publicly available fast
outlets in China and 21,280 in Japan,
Germany, France, Norway, the United
Kingdom and the United States combined (these countries hold 93% of
fast chargers worldwide).
Mexico and Brazil stand out as
leaders in the region with the most
charging stations. Mexico is the only
country in Latin America with Tesla
stores (see the Tesla website, https://
www.tesla.com/, checked in January
2019), which explains why there are 12 Tesla superchargers
and approximately 330 Tesla public outlets. Brazil has two
fast-charger corridors: one between Rio de Janeiro and
Campinas and another between Florianópolis and Foz do
Iguaçu. After Mexico and Brazil, Costa Rica is the next
country with the most publicly accessible chargers in Latin
America. In 2018, Costa Rica passed
legislation for EV incentives, enforcing the deployment of public infrastructure to its eight distribution
companies. Hence, the government
is obliged to plan for the deployment of the country’s charging
infrastructure, and electricity distribution companies must follow suit.
location of level 3 chargers in strategic
places, aiming to provide sufficient
resources to reach every corner of
the country.
To help define the location of these
fast-charging stations, the University
of Costa Rica developed a simplified
methodology (see Figure 3) starting
with preliminary locations that can be
estimated with engineering models or
derived from expert knowledge. It also
uses an EV energy-consumption
model, geo-referenced data, and origin–destination data to define the
corresponding locations. The methodology estimates locations that ensure the availability of
level 3 charging in densely populated areas as well as coverage for long trips.
In the case of the Costa Rican process, preliminary
locations were defined by engaging with key stakeholders
from the electricity and transport sector, who established
Public Charging Stations:
Level 2
8
Level 3
5
Locating Fast Chargers: A Costa
Rican Case Study
Costa Rica in Central America has
almost 5 million inhabitants living
in an area of 19,730 mi2 (51,100 km2).
Its electricity sector is characterized
by a highly renewable power-generation mix and a national electricity
access rate above 99%, as provided
by the eight power utilities.
As part of recent legislation to
promote EVs in Costa Rica (law
9815, official since February 2018),
distribution companies must locate
public chargers across the country
to ensure that EV users can drive
their EVs all over the national territory. Accordingly, there must be a
charging station (level 2 or level 3,
preferably level 3) approximately
every 50 mi (80 km) on national
roads and approximately every
75 mi (120 km) on secondary roads.
As part of a national initiative, the
electricity sector will prioritize the
7
9
6
1
Argentina
2
1
2
Brazil
105
25
3
Chile
21
6
4
Colombia
17
7
5
Costa Rica
47
1
6
Ecuador
4
7
Guatemala
8
Mexico
402
9
Panama
1
10
Paraguay
6
11
Peru
12
Uruguay
1
4
2
11
1
10
23
12
1
3
1
23
Figure 2. The estimated number of publicly available chargers among Latin America countries.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
27
Grid and
Road Data
a list of possible options based on knowledge of the infrastructure (see Quirós-Tortós et al. 2018). These locations
Origin–
Preliminary
Topographic
were evaluated with two purposes in mind: the first
Destination
Locations
Data
allowed analysis of densely populated areas with high
Data
vehicle traffic, and the second ensured that EVs can reach
the farthest town in the country, considering that driving
range varies with topography.
To define the locations in densely populated regions,
Longest Trips
Roads and
such as the greater metropolitan area (GMA), the methodand EV Modeling
Population Density
ology uses origin–destination information to understand
the typical routes between households and study and
Metropolitan
Energy
Locations
Consumption
work places or frequently attended venues (e.g., hospitals).
By representing connected districts as nodes and using
data from the main road system and demographics, the
methodology places fast-charging locations in the GMA by
covering all of the connections (i.e., roads) between the
Legend:
Grid Availability
origin and destination zones (i.e., groups of adjacent disInputs
tricts). The result is that every GMA resident could have
Potential
access to a level 3 charger nearby when the metropolitan
Analysis
Installation Areas
locations are deployed.
Outputs
To estimate whether an EV reaches a destination far
Refined Location Proposal
away from the GMA, the methodology uses altitude profiles
(i.e., topographic data) to analyze the effect of topography
in the routes of interest. In addition, it adopts a model that
Figure 3. The methodology for planning the location of level 3 chargers throughout Costa Rica.
allows the quantification of EV energy consumption while
considering the altitude and other
physical properties of EVs to understand the distances an EV can travel with a given amount of energy
Public Charging Stations:
Level 3
National Roads:
in the battery. Starting from the
center of the country and traveling
through the main roads to the farthest points, the methodology places a fast-charging station when the
GMA
energy consumed reaches a previously defined percentage of battery
capacity, considering a charge of up
to 80% at these stations.
The locations must meet technical requirements, such as the availability of three-phase distribution
lines. To check the fulfillment of
such technical requirements, the
methodology transposes geospatial
Total:
11
San José
x9
data from the electricity system
34
6
Alajuela
and the road system.
Once every main road has its
Cartago
2
corridor of fast-charging stations,
3
Heredia
the methodology checks whether
4
Guanacaste
there are two consecutive charging
Puntarenas
5
stations where energy consumpLimón
3
tion is below an 80% capacity of the
battery and deletes one of them
aiming to create a minimal charging network. Also, stations near the
Figure 4. The locations of proposed public fast-charging stations in Costa Rica.
farthest towns may not be necessary
28
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
in the short term under the premise that, once such a destination is
Input Data
reached, the driver can wait longer
Up-Front Cost of Vehicle Discount Rate TCO Horizon
Vehicle Performance
by using a level 2 charger. The
methodology checks for directions
Typical Yearly Driving Distance Estimated Energy Price Forecast
both to and from the destination to
Estimated Maintenance Cost Over the TCO Horizon
ensure that the EV user can reach
the starting point.
Figure 4 shows the proposal for
TCO Calculations
fast-charging infrastructure in
Costa Rica. The study reports that a
minimum of 34 level 3 chargers can
NPV of Total
Energy (kWh or L)
Energy Cost
cover the growing uptake of EVs.
Expenditures
Consumption
With such a network, new EV owners could complete the drive to any
place in the country, with the
exception of remote locales that Figure 5. The calculation methodology of the TCO.
even comparably sized IC vehicles
have difficulty getting to. A more robust charging network
would enable travelers to reach a destination and quickly
Argentina
return home, because there would be fast-charging sta**Bolivia
tions in the farthest towns.
Brazil
Ultimately, the outcomes from this methodology will
Chile
help Costa Rican policy makers determine the most suitColombia
able places for fast chargers across the country. FurtherCosta
Rica
more, because the methodology requires data that are
**Ecuador
usually available in most countries, it provides the basis
for similar methodologies that can be adopted in other
*El Salvador
Latin American countries (and internationally) where EV*Guatemala
charging infrastructure has yet to be defined.
*Honduras
The Economics of EVs: Total Cost of Ownership
The up-front cost of EVs is usually higher than that of IC vehicles; however, their yearly operation and maintenance costs
are typically lower. Therefore, to understand the cost effectiveness of EVs compared with IC vehicles, it is important to carry
out an economic assessment of total cost of ownership (TCO).
TCO quantifies the financial implications of owning and operating a vehicle over a span of years. The value calculated with
this analysis represents the net present value (NPV) of all
expenses over the ownership period (i.e., the TCO horizon). In
the following sections, we present a methodology for quantifying the TCO of vehicles and the corresponding results for the
region. The latter not only helps with understanding the economic barriers that EVs face in Latin America but also highlights some of the possible ways to promote their uptake.
Calculating the TCO
TCO analysis can include very detailed financial information, such as taxes, financial costs, maintenance, repairs,
costs of fuel (for IC vehicles) or electricity (for EVs), subsidies, and a salvage value when the ownership period
expires. However, obtaining all this information is still
complex in Latin American countries. Therefore, we present a simplified methodology for estimating the TCO of
vehicles in Latin America (see Figure 5).
Mexico
*Nicaragua
Panama
*Paraguay
*Peru
*Uruguay
0
5 10 15 20 25 30 35 40 45 50 61.6
Vehicle Purchase Cost (×US$1,000)
EV
Avg.:US$40,990
IC Vehicle
Avg.:US$21,960
*EV prices are the Latin America average.
**EV and large-sedan prices are the Latin America average.
Figure 6. The up-front vehicle costs in the analyzed Latin American
countries in 2019.
The input data for this methodology include
xx
up-front cost of the vehicle: indicates the retail price of
the vehicle
xx
discount rate: represents the opportunity cost of using
capital to own the vehicle
xx
TCO horizon: defines the vehicle-ownership period
xx
vehicle performance: indicates how much energy (in
kilowatt hours) or liters of gasoline are needed to
travel 1 km
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
29
xx
typical yearly driving distance: allows quantification of
ation and maintenance costs (paid every year of vehicle possession).
yearly energy consumption
xx
estimated energy price forecast: a highly uncertain variable that allows quantification of the cost of driving
the vehicle per year
xx
estimated maintenance cost over the TCO horizon: consists of all costs needed to ensure that the vehicle can
operate (e.g., repairs, replacement of parts, oil changes,
and so on).
The TCO methodology then follows the next steps:
xx
energy consumption: quantifies the yearly energy consumption using vehicle performance and typical yearly driving distance
xx
energy cost: estimates the total energy cost (i.e., operation cost) in US$ for each year of the TCO horizon
by multiplying the energy consumption and the
price forecast
xx
NPV of total expenditures: determines the NPV of each
cost over the years. The costs considered here are
up-front costs (paid at once in the first year) and oper-
What Are the TCO Numbers in Latin America?
30
Uruguay
Peru
Paraguay
*Nicaragua
Mexico
Panama
Mexico
*Honduras
Honduras
Guatemala
El Salvador
Ecuador
Costa Rica
Costa Rica
Chile
Colombia
Colombia
Brazil
Bolivia
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
Uruguay
Peru
Paraguay
Panama
Nicaragua
Guatemala
El Salvador
Ecuador
Chile
Brazil
Bolivia
Argentina
TCO (×US$1,000)
Argentina
Gasoline Price (US$/liter)
Residential Electricity Rate at 500 kWh
Consumption (US$ cent/kWh)
Figure 6 shows the up-front costs per country gathered in
early 2019. (The retail price may be affected by tax exemptions, which are not considered here.) The cost of EVs (e.g., a
Leaf and Ioniq) is always higher than that of IC vehicles
(e.g., a Corolla, Sentra, or Elantra), on average by 187%. The
analysis uses average values when data are not available
(see Figure 5). This analysis excludes Venezuela due to
uncertain data.
Figure 7 then shows the current electricity rates (as of
June 2018) and gasoline prices (as of January 2019) in each
Latin American country. In terms of the forecast for gasoline prices, we use the trend provided by the New Policies
scenario presented at the World Energy Outlook 2018 of
the IEA. The electricity cost forecast follows the trend provided in the Annual Energy Outlook 2018 of the U.S. Energy
Information Administration.
Based on consultations with
vehicle manufacturers, we assume
an average maintenance cost of
US$1,200/year for an IC vehicle.
1.8
25
Although this value is lower during
Avg.:US$ cent 14.25
1.6
the first years of use, it increases sigAvg.:US$
1.01
20
1.4
nificantly after 5 years (according to
1.2
consulted garages). An EV has fewer
15
1
moving parts, so it has much lower
0.8
10
maintenance costs: in this case, 30%
0.6
of the costs for an IC vehicle.
0.4
5
Vehicle performance varies per
0.2
car and country, but we use an EV per0
0
formance of 5.33 km/kWh and an IC
vehicle performance of 13.85 km/L,
similar to that of a large sedan.
Based on typical values from the
*For countries without available data, the average value was used.
economic literature, we use a discount rate of 5%.
Figure 7. The electricity rates in Latin American countries at the end of 2018. Avg.: average.
Figure 8 presents the TCO results,
considering a TCO horizon of 6 years
(i.e., by 2025) and a yearly driving dis70
tance of approximately 12,500 mi
EV
IC Vehicle
60
(~20,000 km), the average value in
50
Costa Rica and assumed for all other
40
countries. For these inputs, Figure 7
highlights that EVs are more cost
30
effective only in Costa Rica. It also
20
shows that Honduras, Panama, Para10
guay, and Uruguay have a TCO dif0
ference lower than US$5,000, which
implies that EVs can become as cost
effective in the short term in these
Latin American countries. In addition, these results highlight the fact
Figure 8. The results of the TCO assessment for a six-year TCO horizon and a yearly driving
distance of 20,000 km.
that countries with lower up-front
costs and electricity prices are more prone to see more benefits from EVs.
From a customer perspective, it is interesting to
understand when the total cost of owning an EV
becomes lower than the cost of owning an IC vehicle. For
this purpose, we introduce the TCO match year, which
indicates the number of years needed to own an EV for it
to be as cost effective as an IC vehicle (considering a
yearly driving distance of 20,000 km and the same energy
and vehicle costs described). Figure 9 shows the countries whose TCO match year is fewer than 20 years; only
10 countries meet this criterion. More importantly, Figure
9 highlights the fact that there are three counties (Costa
Rica, Panama, and Uruguay) with a TCO match year
fewer than 10 years, which, in turn, indicates that people
living in these countries are likely to get more economic
benefits from EVs much faster than in other countries.
Latin America. We also listed the number of public charging stations available in different countries and described
a simplified methodology, developed in Costa Rica, for
defining the location of fast-charging stations. Finally, we
presented the results of an economic assessment of EVs
to understand the corresponding cost effectiveness and
highlight potential actions policy makers can take to promote greater EV adoption. The key conclusions are summarized as follows.
Incentives Today
Similar to other regions, Latin American countries are
deploying financial (e.g., reducing taxes) and nonfinancial
incentives (e.g., dedicated parking spaces) to promote the
uptake of EVs. Because import and value-added taxes represent, on average, approximately 65% of the total tax in
the region, Latin American countries are applying tax
What Does It Take to Make EVs
as Cost Effective as IC Vehicles?
The TCO methodology can be adapted to quantify the incentives needed
to make EVs as cost effective as IC
vehicles for a given period and a
given yearly driving distance. This
can help policy makers in the region
promote tax exemptions or rebates
to increase the uptake of EVs.
Table 4 shows the required incentive per country to make EVs as
cost effective, considering 20,000 km
and 6 years of ownership. As mentioned, policy makers in Honduras,
Panama, Paraguay, and Uruguay
need to provide a relatively low
incentive (<US$5,000) to promote
the deployment of EVs, and this represents approximately 10% of the
up-front cost of an EV. This assessment also shows that, on an average, 22% of the retail cost of EVs in
Latin America is needed to incentivize their deployment in the region.
This assessment can be carried
out for different years and yearly
driving distances to cater to the
characteristics of each country.
However, for all of these cases, the
methodology can be used to inform
policy makers about the different
options they have to promote EVs.
TCO Match Year
5
Yearly Driven Distance:
20,000 km
3
4
7
6
1
Brazil
19
2
Chile
17
3
Costa Rica
6
4
Honduras
11
5
Mexico
13
6
Nicaragua
15
7
Panama
8
8
Paraguay
10
9
Peru
17
10
Uruguay
9
1
9
8
10
2
What Can Be Learned
From the Region?
We presented an overview of the
different incentives in place in
Figure 9. The TCO match year between EVs and IC vehicles considering a yearly driving distance
of 20,000 km.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
31
TABLE 4. The incentive needed per country
to make EVs as cost effective as IC vehicles,
considering a driving distance of 20,000 km
and 6 years of ownership (values rounded up).
Country
Required
Incentive (US$)
Incentive/UpFront Cost (%)
Argentina
25,821
42
Bolivia
11,545
28
Brazil
10,270
21
Chile
9,942
25
Colombia
16,391
39
Costa Rica
EVs are already cost effective
Ecuador
12,149
30
El Salvador
8,060
20
Guatemala
11,498
28
Honduras
4,308
11
Mexico
6,517
18
Nicaragua
6,995
17
Panama
1,557
5
Paraguay
4,135
10
Peru
8,339
20
Uruguay
4,759
12
reductions or exemptions to these types of taxes to lower
the up-front cost of EVs, which is one of the main barriers
to EV ownership. Incentives that reduce the yearly costs of
owning and/or using EVs are also deployed in the region,
but these have a lower impact on the economics of EVs.
Waivers on driving restrictions (e.g., license-plate-based
restrictions) and dedicated parking spaces are two suitable
nonfinancial incentives, as their implications are usually
low. The allowance to use bus-only lanes, however, can
be detrimental to urban transportation sustainability,
because it may result in more people leaving the public
transportation system.
Charging Infrastructure
Public charging infrastructure is important to promote the
uptake of EVs (see the “Charge Ready Program from
Southern California Edison” for initiatives in the United
States). There are multiple online platforms that report
location, availability, and other information related to public charging stations, particularly for level 2 (semirapid)
and level 3 (fast). There are approximately 628 level 2 chargers (90.5%) and 66 level 3 chargers (9.5%) in Latin America. Overall, Mexico, Brazil, and Costa Rica are leading in
the region, with 85% of the total (level 2 plus level 3) public
chargers. Costa Rica is making significant progress in
terms of public chargers, and, as a result of a recently
enacted law, charging stations must be placed strategically.
32
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
We presented a methodology for this purpose that aims to
provide sufficient resources to reach every corner of the
country. This methodology can be adopted in other Latin
American countries (and internationally) where charging
infrastructure has yet to be defined.
Cost of Owning an EV
The cost effectiveness of EVs, compared with IC vehicles,
can be understood through a TCO analysis. We presented
a simplified methodology that allows the quantification of
total expenditures (as net present values) of the up-front,
operation, and maintenance costs paid every year of vehicle possession. Given the set of assumptions (due to data
unavailability), the results show that EVs in Costa Rica are
already effective when people drive more than 20,000 km
per year and own the vehicle for at least 6 years. EVs in
Panama and Uruguay become cost effective after 8 and 9
years if people still drive 20,000 km per year. Maintaining
this yearly driving distance, people in all the other Latin
American countries require more than 10 years of ownership or the introduction of financial incentives that reduce
the up-front cost of EVs. The developed TCO methodology
was adapted to quantify the financial incentives needed
per country to make EVs as cost effective by 2025. On average, the region requires a reduction of 22% in the retail
cost of EVs, which could be achieved through tax cuts.
For Further Reading
International Energy Agency, “Global EV outlook 2018: Towards
cross-modal electrification,” Paris, France, May 2018. [Online].
Available: https://webstore.iea.org/global-ev-outlook-2018
J. A. Gómez-Gélvez, C. Hernán Mojica, V. Kaul, and L. Isla,
The Incorporation of Electric Cars in Latin America, Inter-American
Development Bank, 2016.[Online]. Available: https://publications
.iadb.org/publications/english/document/The-Incorporationof-Electric-Cars-in-Latin-America.pdf
J. Quirós-Tortós et al., “Propuesta de ubicación de la infraestructura de recarga rápida para vehículos eléctricos en Costa
Rica,” Sept. 2018. [Online]. Available: https://sepse.go.cr/documentos/
Propuesta-de-ubicacion-de-L3.pdf.
J. Quirós-Tortós, L. F. Ochoa, and T. Butler, “How electric
vehicles and the grid work together: Lessons learned from
one of the largest electric vehicle trials in the world,” IEEE
Power Energy Mag., vol. 16, no. 6, pp. 64–76, Nov.–Dec. 2018. doi:
10.1109/MPE.2018.2863060.
Southern California Edison, “Charge Ready Program—Fact
sheet.” [Online]. Available: https://www1.sce.com/wps/wcm/
connect/ff38bcac-8460-47ff-81d0-66ec4c3d7887/Charge_
Ready_EVSE_Fact_Sheet.pdf?MOD=AJPERES
Biographies
Jairo Quirós-Tortós ([email protected]) is with the
University of Costa Rica.
Luis Victor-Gallardo ([email protected]) is
with the University of Costa Rica.
Luis (Nando) Ochoa ([email protected]) is with the
University of Melbourne, Australia, and the University of
Manchester, United Kingdom.
By Hamidreza Nazaripouya, Bin Wang, and Doug Black
©ISTOCKPHOTO.COM/FARUKULAY
LIMATE AND WEATHER PATTERNS ARE
changing in California and across the planet. Extreme weather events such as wildfires are happening more frequently,
precipitation has become increasingly variable, heat waves are more common, and temperatures are
warming. Climate and weather scientists have tracked the
observed changes since the mid-20th century and linked
them mainly to human activity and influence. The human
activity, including the burning of fossil fuels, has led to a
significant release of carbon dioxide and other greenhouse gases into the atmosphere, which disrupts the global carbon cycle and leads to global warming.
C
According to the 2018 California Energy Commission
report, in that state, transportation is the largest source of
greenhouse emissions, accounting for about 40.6% of the
total and more than 50% when emissions from refineries
are included. Given this, the fundamental effort of California for reducing greenhouse gas emissions is to transform
the transportation system from gasoline to electric vehicles (EVs), aligned with Senate Bill 350 encouraging transportation electrification.
Currently, EVs make up only a small percentage of the
auto market. In 2017, the new EV sales market share in
California was 4.92%; for the United States, this number
was 1.18%. Obstacles to increasing EV market share
Electric Vehicles
and Climate Change
Additional contributions and improved economic justification.
Digital Object Identifier 10.1109/MELE.2019.2908792
Date of publication: 11 June 2019
2325-5987/19©2019IEEE
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
33
The aim of this
article is to study
the extra potential
value of EVs to end
users, EV fleet
aggregators, utility
companies, and
system operators.
include high vehicle costs and lack of
a clear economic justification for
manufacturers and end users. The EV
industry still relies on federal and
state subsidies, and there is a debate
about whether the industry can stand
on its own feet without these supports. Currently, the major force
behind federal and state efforts to
promote EVs is clean transportation
goals, and the only economic incentive for EV users is the fuel cost savings. The aim of this article is to study
the extra potential value of EVs to end
users, EV fleet aggregators, utility
companies, and system operators. The objective is to
improve the economic justification for EVs and encourage
deployment of the technology, not only because of environmental concerns but also for the services it can provide in terms of grid reliability, security, and resilience.
EV and Electricity Markets
The current power grid faces a future for which it was
not designed. This includes dealing with high variability
in power supply due to large-scale integration of renewable energy resources, a rapidly aging infrastructure that
threatens grid resilience and reliability, and the additional burden placed on the grid by the widespread
adoption of EVs. Although high demand and the stochastic nature of EV loads might be considered as challenges for grid operation, the EV as a mobile and flexible
energy storage system brings new opportunities to
manage the grid. EVs are assets in the grid that can
address future challenges by providing grid services traditionally reserved for conventional generation resources such as peaking units and battery storage systems.
Proper coordination and optimal charging of EVs enable
them to participate in energy and ancillary service markets across the network.
According to a U.S. Department of Transportation
report, personal vehicles in the United States were driven
for 56.1 min/day on average in 2009. While they are parked
for about 23 h/day, these EVs could achieve the secondary
purpose of providing valuable services to the grid, including ancillary services, emergency backup power, and
demand profile leveling, on a daily basis. This could help
the local and state-wide community improve the economics and reduce environmental costs of stable power, prevent black-out scenarios, and reduce the timing
imbalance between peak demand and renewable energy
production, besides contributing to greenhouse gas emissions reductions.
The California Independent System Operator (CAISO)
offers wholesale market aggregators the proxy demand
resource (PDR) product, which enables aggregators to offer
demand-response resources directly into the wholesale
34
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
energy and ancillary service markets.
It also allows non-generator resources
(NGRs) to bid their 15-min capacity
into the regulation market. PDR
resources can bid economically into
the following markets: 1) the dayahead energy market with a minimum load curtailment of 100 kW, 2)
the day-ahead and real-time nonspinning reserve market with a minimum load curtailment of 500 kW, and
3) the 5-min real-time energy market.
Additionally, smaller loads may be
aggregated to achieve minimum load
curtailment. It should be noted that
PDR is only a load curtailment product and is not enabled
for load increase.
In this article, we show how EVs as deferrable loads can
participate in electricity markets and be optimally shifted
to various timespans and so meet grid objectives in different markets. In the following, we discuss some of the
potential programs for EV participation and then present
a real-world case study, including detailed specifications
of the EV fleet and quantified benefits.
Time-of-Use Tariff Structure
To alleviate stress on the grid and reduce load during peak
demand hours, utilities in California offer time-of-use
(TOU) pricing, which includes lower prices during lowdemand periods. EV owners can benefit from this program
and reduce their bills by cooperating with utility companies in distributing the loads over time and improving the
load factor. In California, for commercial customers under
the TOU tariff structure, two categories of costs are generally applied: energy charge and demand charge. Energy
charges are calculated as the product of electricity energy
amount, measured in kilowatt hours (kWh) per time period, and the per-kWh rate corresponding to the time period. Demand charge is calculated based on the maximum
power measured in each demand period multiplied by the
corresponding demand charge rate, in US$/kW. Adopting
an optimal EV charging schedule and/or equipping EVs
with vehicle-to-grid (V2G) capability (i.e., sending energy
back to the grid during peak demand) can minimize
monthly energy bills and contribute to reducing the load
on the power grid.
Peak-Day Pricing Plan
Peak-day pricing (PDP) is a time-varying rate structure that
offers higher rates during peak-usage periods and lower
rates at other times. The higher-rate events typically occur
on the hottest days of the summer. According to Pacific
Gas and Electric (PG&E), customers participating in PDP
can expect between nine and 15 PDP event days in addition to TOU pricing each year. On event days, an extra
charge is added to the regular TOU rate during the peak
period: for example, under PG&E’s E-19
tariff program, the peak period is from
2 p.m. to 6 p.m. In return, customers
receive discounts on regular summer
electricity rates.
When participating in this program, customers must elect a capacity
reservation level (CRL) based on their
historical data usage measured every
15 min. During PDP events, the energy
usage below the CRL is protected and
billed at non-PDP rates (e.g., the TOU
rates), while usage above the CRL is subject to PDP rates
with higher energy and demand charges. In this program,
regular summer rates are discounted.
customers the opportunity to receive
financial incentives for reducing loads
on event days. Credits are based on
the difference between the customer’s
actual metered load during an event
and a baseline load calculated from
the customer’s usage data prior to the
event. For the most part, customers
are notified of events by noon the previous day. That is, DBP events are dispatched in day-ahead operations;
thus, preplanning is necessary for
optimizing the benefits. Aggregated EVs can be utilized as
valuable resources in response to DBP events, following virtual-battery modeling approaches similar to those used for
the PDR programs.
The EV as a mobile
and flexible energy
storage system
brings new
opportunities to
manage the grid.
Ancillary Service Market
According to the U.S. Federal Energy Regulatory Commission, ancillary services are “those services necessary to
support the transmission of electric power, to maintain
reliable operations of the interconnected transmission
system.” Ancillary services are utilized to achieve instantaneous supply–demand balance in electric transmission
systems by calling services from various grid components—not only traditional electricity generators but also
demand-side distributed energy resources. A regulation
up/down market is a representative type of ancillary service market. EVs with the capability to follow the regulated up and down signals within a short period of time can
be coordinated to serve as effective and reliable resources
for regulation services
Case Study Results and Discussion
A parking garage located in Oakland, California, was
selected as the testing facility for performing a case study.
The real-world data sets for this facility were collected
from the PG&E utility electric meter. The data sets include
four years of historical building load, public and fleet EV
itineraries, and energy demand records for more than
20,000 EV charging sessions. The detailed fleet information
is included in Table 1. Information on the charging stations installed at the demonstration site and used in
this study is listed in Table 2.
TABLE 1. EV fleet information for the case study.
PDR Market
The PDR program in California allows end-use customers
to bid demand-response services directly into CAISO’s
wholesale day-ahead and real-time markets through a
demand-response provider as PDRs. Aggregated EVs can
participate in the PDR market, where fleet EVs are treated
as a “virtual battery” with the flexibility to sell their power
in the PDR market. For EVs with V2G capabilities, sell
operations can be achieved by discharging the vehicle
batteries; for smart-charging vehicles (V1G), selling power
would be achieved by reducing the aggregate power consumption relative to the baseline of the load profile.
CAISO uses a baseline energy calculation to determine
the amount of energy curtailed.
PHEV Model
Battery Capacity
(kWh)
Number
Nissan Leaf
24
12
Chevy Bolt
60
2
Ford Focus Electric
23
17
Toyota RAV4
41.8
2
Toyota Prius
4.4
2
Chevy Volt
16.5
2
Ford C-Max Energi
7.6
3
PHEV: Plug-in hybrid electric vehicle.
Demand Bidding Program
To increase system reliability, some utility companies are
paying additional incentives to industrial, commercial, and
agricultural customers to reduce their energy consumption
during certain time periods. Demand bidding programs
(DBPs) at Southern California Edison and PG&E are examples of this. According to program documents from the
California Public Utilities Commission, a DBP is a voluntary
demand-response bidding program that provides enrolled
TABLE 2. Charging station information.
Ports
Charger Model
Number
Level 1
Level 2
CT2100
14
1
1
CT4020
11
0
2
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
35
0.4
Minimum: 0
Maximum: 1
Mean: 0.3972
Median: 0.3602
Probability
0.3
0.2
0.1
0
0
0.2
0.4
0.6
Flexibility
0.8
1
Figure 1. The probability distribution of the charging session
flexibility index.
TABLE 3. PG&E’s E-19 demand charge and energy
charge rates.
Demand Charges
US$/kW
Time Period
Maximum peak
demand, summer
US$18.74
Noon–6:00 p.m.
Maximum part-peak US$5.23
demand, summer
8:30 a.m.–Noon
and 6:00–9:30 p.m.
Maximum demand, US$17.33
summer
Any time
Maximum part-peak US$0.13
demand, winter
8:30 a.m.–9:30 p.m.
Maximum demand, US$17.33
winter
Any time
Energy Charges
US$/kWh
Time Period
Peak, summer
US$0.14726 Noon–6:00 p.m.
Part-peak,
summer
US$0.10714 8:30 a.m.–Noon
and 6:00–9:30 p.m.
Off-peak,
summer
US$0.08057 Any time
Part-peak,
winter
US$0.10166 8:30 a.m.–9:30 p.m.
Off-peak, winter
US$0.08717 Any time
Electric Bill (US$)
10,000
8,000
TOU Market Participation
The first study includes load shifting and cost reduction through smart charging and scheduling optimization under TOU prices only. Table 3 summarizes
demand charge and energy charge rates according to
PG&E tariffs. As shown in Table 3, the energy charge
and demand charge rates in winter are lower than
those in summer. As a result, the test site’s actual total
monthly costs for energy charges in winter were slightly lower than those for summer, indicated by the blue
bars in Figure 2. In addition, the total monthly demand
charges in winter were considerably lower than those
in summer, shown in Figure 2 by the orange bars.
Two separate optimization problems with different
cost objectives are defined as use cases. The first cost
objective includes only the total monthly energy charge;
the second includes the summation of total monthly
energy and demand charge. The load profile of two consecutiive days with the maximum monthly demand in
June is shown in Figure 3, with (a) and (b) corresponding
to minimization of the first and second cost objectives,
respectively. In Figure 3(a), a large portion of the EV load
has been shifted to time periods with lower energy
charge rates; in Figure 3(b), the monthly load peak
around 10 a.m. is shaved to minimize the monthly
demand charge.
6,000
4,000
Ancillary Service Market Integration
2,000
In this section, another capability is enabled that allows
EVs to participate in ancillary service markets in addition
to the TOU market. The day-ahead prices for ancillary service regulation up and down are collected from CAISO’s
Open Access Same-Time Information System (OASIS) for
two years. As shown in Figure 4, the EV load profile
becomes spikier when supporting ancillary service market
0
Months
Energy Charge Cost
Demand Charge Cost
Figure 2. The actual total monthly cost of energy and demand charges
at the test site for two years starting from January, in chronological order.
36
The deferability of the EV charging load can be denoted
by the flexibility index, defined by the actual charging
time in each session divided by the total plug-in time. The
distribution of the flexibility indices for all collected charging sessions in this study is shown in Figure 1.
In this case study, the charging scheduling problem
for EVs is formulated as an optimization problem based
on mathematical models of each market. The mathematical model includes the physical and market constraints imposed on the participation of EVs in the
electricity market (e.g., state of charge and power and
energy capacity) as well as an objective function that
aims to maximize EV revenue and minimize the testing
facility electricity bill.
This section demonstrates the optimization results of
EVs participating in the demand-response programs and
ancillary service markets described in the previous section. The benefit analysis is conducted based on real data
from the testing facility as well as pricing information
from PG&E and CAISO.
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
TABLE 4. Monthly revenue from the
Power (kW)
Part-Peak Region
Shifted Load
100
50
150
12:00
24:00
(a)
12:00
24:00
Shaved Peak
100
50
00:00
12:00
24:00
(b)
12:00
24:00
Baseload (kW)
Optimized EV Load (kW)
Original Building Load (kW)
Figure 3. An example load profile showing the smart-charge EV load
shifting to minimize electric costs for two consecutive days. In June:
(a) minimization of the first cost objective and (b) minimization of the
second cost objective.
Power (kW)
regulation market.
150
00:00
Power (kW)
Peak Region
120
110
100
90
80
70
60
50
40
30
00:00
Year
Ancillary
Service
Month Revenue
Year
Ancillary
Service
Month Revenue
2015
1
US$90.38
2016
1
US$74.53
2015
2
US$66.42
2016
2
US$66.33
2015
3
US$73.88
2016
3
US$90.37
2015
4
US$95.73
2016
4
US$71.75
2015
5
US$78.09
2016
5
US$68.62
2015
6
US$67.75
2016
6
US$95.70
2015
7
US$76.57
2016
7
US$69.22
2015
8
US$68.51
2016
8
US$77.28
2015
9
US$78.16
2016
9
US$61.50
2015
10
US$80.48
2016
10
US$78.24
2015
11
US$63.24
2016
11
US$79.70
2015
12
US$98.11
2016
12
US$115.14
The monthly revenue results are simulated by applying
EV management strategies over two selected years, as
shown in Table 4. The highest monthly revenue is calculated as US$115 for December 2016, and the lowest revenue
obtained is US$61.50 for September 2016.
PDR Market Participation
12:00
24:00
12:00
24:00
Baseload (kW)
Optimized EV Load (kW)
Original Building Load (kW)
Figure 4. An example load profile for two days of ancillary service
regulation up and down market participation.
participation, because optimization tends to change
power consumption when a high regulation price signal is
anticipated. However, with the possibility that the
increased EV charging load causes new demand peaks
and thus high demand charges, optimization evaluates
the tradeoff globally on a monthly basis. As depicted in
Figure 4, the adjusted power consumption profiles due to
participation in the regulation market are constrained so
as not to exceed the monthly demand peaks set by the
TOU-based optimization.
In this study, the duration of each regulation commitment during optimization is 15 min, within which the
actual regulation signals are dispatched every 4 s. A
15-min interval is considered as the finest resolution for
EV control. In addition, both regulation up and regulation
down bids are allowed in the same time periods.
The same analysis is conducted for PDR market integration
by combining the TOU charges with the revenues from the
PDR markets as the objective function. Figure 5(a) shows the
day-ahead PDR price for two consecutive days. In California,
CAISO requires that each participant in the PDR market have
at least a 1-h commitment. Therefore, additional constraints
must be applied on the optimization problem to guarantee
that each market participation event spans more than four
time steps (15 min per step). As shown in Figure 5(b), the
green curve indicates the actual EV power consumption profile, while the red curve represents the virtual sell power of
the EV aggregator given price signals from the PDR market.
Note that the total energy consumption according to the
actual power consumption profile is equal to that calculated
from the baseline profile. In addition, in this problem, the
participation of EVs in the PDR market is modeled with a
binary variable, which reflects that the EV aggregator does
not have to stay in the market for the entire day and can
plan to participate in the market when PDR prices are economically desirable. Table 5 summarizes the calculated
monthly revenues from PDR markets.
DBP Participation
DBP market integration has many similarities with PDR
market participation. The main difference is that the DBP
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
37
Price (US$/kWh)
market occurs only when DBP events are issued by the program facilitator, whereas hourly price signals in the PDR
market are available daily. In PG&E’s DBP program, the fixed
rate of US$0.5/kW is credited to commercial customers
0.1
0.05
0
–0.05
00:00
12:00
24:00
12:00
24:00
Day-Ahead PDR Price (US$/kWh)
Power (kW)
(a)
50
0
–50
00:00
12:00
24:00
12:00
24:00
Baseline (kW)
Virtual Sell Power (kw)
Actual Power (kW)
(b)
Figure 5. The results of PDR market participation: (a) PDR price (in
US$/kWh) and (b) baseline, virtual sell, and actual powers (in kW).
TABLE 5. Monthly revenue from the PDR market.
Year
PDR
Month Revenue
Year
PDR
Month Revenue
2015
1
US$29.20
2016
1
US$26.76
2015
2
US$17.44
2016
2
US$32.45
2015
3
US$34.12
2016
3
US$35.92
2015
4
US$33.76
2016
4
US$30.16
2015
5
US$31.74
2016
5
US$24.23
2015
6
US$22.64
2016
6
US$46.00
2015
7
US$21.39
2016
7
US$12.96
2015
8
US$29.07
2016
8
US$24.79
2015
9
US$31.48
2016
9
US$20.76
2015
10
US$32.22
2016
10
US$29.67
2015
11
US$20.40
2016
11
US$18.81
2015
12
US$35.27
2016
12
US$52.72
TABLE 6. Monthly revenue from the DBP
market.
38
when they reduce their demand during DBP events. The
results for DBP market participation in this study are shown
in Table 6. It is assumed that the power capacity threshold
for participation is greater than or equal to 10 kW and that
each commitment should be at least 2 consecutive hours in
duration. Due to the 2-h commitment constraint, existing
EV resources were not qualified to participate in all 2016
DBP events. Thus, the profit-generating capacity for EVs is
not as high as that for the regulation market.
Year
Month
Event Number
Revenue
2016
6
5
US$16
2016
7
6
US$10
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
PDP Participation
For the PDP market integration analysis, the impacts of the
CRL on monthly PDP revenues are studied by selecting different values for historical PDP events. The monthly peaks
above the CRL receive PDP credits, while the energy usage
is not protected by the CRL and is billed at a fixed PDP rate.
PDP events are issued only during summers and only during peak and part-peak demand periods. The monthly PDP
benefit is calculated by subtracting the monthly event
energy charge from the summation of PDP credits for peak
demand and part-peak demand periods. In Figure 6, PDP
benefits for summer months in 2016 are shown with varying CRLs. For months with only one PDP event, i.e., August
and September, PDP credits dominate the total benefit,
which decreases as the CRL increases. On the contrary, in
months with more PDP events, when the CRL increases
from 10 kW to 60 kW, the energy charge becomes dominant because there is less unprotected energy usage. As
the CRL increases to greater than 60 kW, the monthly benefits decrease because of the weaker protection by the CRL.
The annual total PDP benefit varies with the CRL, where
the optimal CRL value is close to 40 kW.
Summary
Given the increase of EV penetration in recent years and
future potential growth, California is in a unique position
to use these resources to provide services to the grid,
including reducing peak demand, mitigating the timing
imbalance between peak demand and renewable energy
production, stabilizing the grid, and compensating for the
impacts of intermittent resources. These are in addition
to EVs’ contributions in reducing greenhouse gas emissions. EVs with V1G (smart charging) capabilities can alleviate the grid stress associated with vehicle charging in
times of load ramps and peak demand through demandresponse programs. Also, EV owners who consume energy sustainably can benefit from reduced charging costs
through TOU pricing, PDP, ancillary service, PDR, and DBP
programs. Using aggregators, EVs with V1G capabilities
can also provide a range of services to the grid, including
regulation services, for which the providers/owners
would be compensated. This provides the scope for EVs to
help reduce the investment needed from local authorities
and utilities for grid maintenance equipment, lowering
costs associated with reliability measures, which can, in
turn, lead to reduced energy costs.
500
PDP Revenue (US$)
400
300
200
100
0
–100
–200
–300
0
20
40
60
80
100
Capacity Reserve (kW)
120
140
arbitrage, and more. However, there is a long debate regarding
the impact on battery life of charging and discharging EVs
and how to calculate the actual revenue generated, which are
both out of the scope of this article.
Finally, proper regulation and standards can promote
and facilitate the use of this technology and encourage
stakeholders to invest more in the EV industry. Investors
and stakeholders should have a clear and accurate understanding of market models. To this end, the regulatory
environment should offer them this vision as well as
attractive incentives, while removing the regulatory
restrictions that prevent them from collecting revenue.
Acknowledgments
June 2016, Five PDP Events
July 2016, Five PDP Events
Aug. 2016, One PDP Event
Sept. 2016, One PDP Event
Annual, 12 PDP Events
The research described here was funded by the California
Energy Commission under Work for Others Contract EPC14-057 and supported by the U.S. Department of Energy
under Contract DE-AC02-05CH11231.
Figure 6. The impact of capacity reserve on PDP benefits.
TABLE 7. Monthly revenue for combined
programs in the case study.
Combined
Programs
TOU+AS
TOU+PDR
TOU+DBP
TOU+PDP
Monthly
Revenue
US$61.50 US$12.96
–115.14
–52.72
US$0–16
US$80–
480
V1G capability is not only useful for supporting the
grid but may also protect battery health and prolong battery life. The main factors that affect battery life are the
average state of charge (SOC), the charging power level,
and the amount of charge transfer. Smart charging, by
keeping the average SOC and charge transfer low, can
improve battery life.
Our investigation found that there are some variations in revenue generated by EVs based on the combination of service type, seasonal pricing, and territory of
operation. Table 7 summarizes the range of monthly revenues for different combinations of programs in this case
study. Despite this residual uncertainty concerning the
provided value, it is nonetheless evident that EVs have
the potential to generate significant revenue for all stakeholders, with earnings proportional to the extent of their
integration. Additionally, there are certain geographic
areas where EVs can have greater value, including those
highly dependent on renewable energies, and those likely to have congestion, all of which can promote increased
integration of EVs and better justify their economics.
In this article, we investigated only the potential value created by V1G capability. Although adding V2G capability provides EVs with more flexibility in electricity markets (and
consequently more value) by allowing participation in spinning/nonspinning reserves, voltage regulation, energy
For Further Reading
A. Santos, N. McGuckin, H. Y. Nakamoto, D. Gray, and S. Liss,
“Summary of travel trends: 2009 national household travel
survey,” U.S. Federal Highway Admin., Washington, DC, Rep.
FHWA-PL-ll-022, June 2011. [Online]. Available: https://nhts
.ornl.gov/2009/pub/stt.pdf
D. Black, J. MacDonald, N. DeForest, and C. Gehbauer, “Los
Angeles Air Force Base vehicle to grid demonstration,” presented at the CalCharge Battery Consortium Kick-off, Lawrence Berkeley Nat. Lab., May 2013. [Online]. Available: https://
escholarship.org/uc/item/7jh4d3t7
D. Black, R. Yin, and B. Wang, “Smart charging of electric
vehicles and driver engagement for demand management
and participation in electricity markets,” Lawrence Berkeley
Nat. Lab., Apr. 2018. [Online]. Available: https://www.energy
.ca.gov/2019publications/CEC-500-2019-036/CEC-500-2019-036.pdf
B. Wang, Y. Wang, H. Nazaripouya, C. Qiu, C. C. Chu, and R.
Gadh, “Predictive scheduling framework for electric vehicles
with uncertainties of user behaviors,” IEEE Internet Things J.,
vol. 4, no. 1, pp. 52–63, 2017.
S. Parvar, H. Nazaripouya, and A. Asadinejad, “Analysis
and modeling of electricity market for energy storage systems,” presented at the 10th Conference on Innovative Smart
Grid Technologies (ISGT 2019), Washington DC, 2019, pp. 1–5
S. Narayana Gowda, T. Zhang, H. Nazaripouya, C. Kim, and
R. Gadh, “Transmission, distribution deferral and congestion
relief services by electric vehicles,” presented at the 2019 IEEE
Innovative Smart Grid Technologies North America Conf.,
Washington, DC, Poster 2019ISGT0020.
California Independent System Operator, “What the duck
curve tells us about managing a green grid,” 2016. Accessed
on: Jan. 11, 2013. [Online]. Available: https://www.caiso.com/
documents/flexibleresourceshelprenewables_fastfacts.pdf
Biographies
Hamidreza Nazaripouya ([email protected]) is with the
University of California, Riverside.
Bin Wang ([email protected]) is with Lawrence Berkeley
National Laboratory, California.
Doug Black ([email protected]) is with Lawrence Berkeley
National Laboratory, California.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
39
By Jonathan Donadee,
Robbie Shaw, Oliver Garnett,
Eric Cutter, and Liang Min
Potential
Benefits of
Vehicle-to-Grid
Technology
in California
High value for capabilities beyond
one-way managed charging.
Digital Object Identifier 10.1109/MELE.2019.2908793
Date of publication: 11 June 2019
40
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
©ISTOCKPHOTO.COM/CABORI
ITH ELECTRIC VEHICLES (EVs) RAPIDLY
becoming more popular, along with a need
for flexible energy storage resources in the
electric grid, the development of vehiclegrid integration (VGI) technology has taken
on a new urgency. VGI encompasses any technology that
helps EVs better integrate with the grid, including management of charging and control of bidirectional charging
and discharging. The practice of managing the one-directional flow of power from the grid to vehicles (V1G) is currently being rolled out across California and in many
W
2325-5987/19©2019IEEE
is reluctant to invest in developing and deploying V2G
technology. As part of CEC-funded project 14-086, Distribution System Aware Vehicle to Grid Services for Improved
Grid Stability and Reliability, Energy and Environmental
Economics, Inc. (E3) was tasked with quantifying the
potential benefits of V2G technology for California’s ratepayers across a variety of use cases. In this article, we
share results and key insights from E3’s study. We believe
that these results provide regulators and industry with the
critical information necessary to help identify the best
opportunities for V2G technology in California.
Modeling the Electric Grid Benefits of V2G
Optimized Dispatch Using the CEC
Solar + Storage Tool
To estimate the electric grid benefits of V2G, we conducted a case study covering several scenarios and use cases
between the present and the year 2030. The case study
was performed using the CEC Solar + Storage Tool developed by E3. New EV-specific modeling and dispatch optimization features were added to the tool, including the
unique constraints that transportation creates for EVs
used as DERs. The model optimizes a joint-dispatch
schedule for a group of EVs that plug in at a common
60
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EV SOC
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(10)
Price (US$/kWh)
(kWh)
places where EVs have become popular. V1G programs in
California include San Diego Gas and Electric’s Power Your
Drive, EV-specific retail tariffs from Southern California
Edison, and the Charge Forward smart charging pilot program from Pacific Gas and Electric in collaboration with
automaker BMW.
The capability to inject power from an EV’s battery
into the electric grid is known as vehicle-to-grid (V2G).
Adding V2G capability to EVs would enable them to deliver much greater benefits to the electric grid than V1G.
There are, however, significant barriers to the widespread
deployment of V2G, including the development of standards for information exchange, regulatory frameworks,
and business models. These barriers are similar to those
facing other distributed energy resources (DERs) but are
even more complex because vehicles are mobile and
require the flexibility to connect to a variety of EV service
equipment (EVSE) and charge or discharge at many different locations.
Another key barrier to further development and
deployment of V2G identified at the California Energy
Commission’s (CEC’s) recent VGI Roadmap Update Workshop is a lack of knowledge about the value that V2G can
provide and what the most promising V2G use cases are
for capturing that value. Without this knowledge, industry
Charge Work
–0.02
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Work Discharge
Home Discharge
60
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50
0.1
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(kWh)
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(a)
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–0.02
Hour of Day
(b)
Figure 1. (a) A V1G and (b) a V2G dispatch during solar overgeneration for a single EV at home on a weekend day.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
41
12 54.77 54.62 54.04 53.46 53.45 53.04 54.35 54.87 55.22 52.71 53.53 51.31 48.5 46.95 44.02 49.76 50.81 53.44 55.59 54.94 55.45 54.35 55.46 55.16
11 50.74 50.87 51.7 51.61 51.44 51.33 52.04 50.98 45.54 43.55 43.1 40.24 39.31 38.56 40.92 47.23 50.26 50.85 52.2 51.67 51.38 52.23 52.14 51.37
47.9 48.07 49.05 50.66 49.81 39.49 39.51 34.44 34.23 34.37 36.71 40.92 45.72 49.15 50.85 52.71 53.36 52.29 52.89 51.44 49.54
10 49.41 49.14 48.4
9 52.61 52.31 51.28 50.12 50.51 51.22 50.32 45.33 39.61 38.39 35.85 36.48 36.5 38.03 43.22 47.12 50.07 55.03 54.94 53.82 54.99 55.3 53.88 52.94
54.8 56.96 54.62 51.93 53.97 53.8 52.25
8 53.44 53.09 52.51 51.42 52.14 52.25 50.87 44.99 38.58 37.64 37.01 36.29 37.48 37.01 43.42 46.16 49.1
7 49.38 49.86 50.59 50.31 51.6 52.87 48.33 44.28 38.9 36.17 35.61 35.44 34.72 35.22 41.21 44.1 47.59 51.18 53.84 53.42 50.89 52.72 51.86 50.41
6 45.15 45.93 45.98 45.9 45.14 45.15 43.2 38.85 30.47 28.79 26.33 21.45 22.31 24.9 32.23 34.95 42.26 48.1 50.12 48.42 47.35 49.71 49.6 45.47
5 42.15 42.57 42.44 42.44 42.45 42.86 41.66 31.41 21.33 20.21 17.26 16.05 16.96 18.1 24.73 31.22 34.32 42.16 45.06 45.87 45.66 46.49 46.76 43.48
42.4 43.14 43.69 36.22 27.46 23.45 20.36 4.09 –2.32 11.41 24.31 32.02 37.81 44.13 46.73 46.54 46.47 46.56 46.41 43.83
4 42.35 42.91 42.97 42.7
3 48.43 47.91 47.61 47.63 47.41 47.87 49.1 49.01 37.5 33.93 30.38 20.97 19.35 27.16 28.61 34.7 44.12 47.98 48.98 49.5 49.65 49.49 48.85 48.13
2 51.67 52.02 52.01 51.55 51.6 51.83 53.87 54.15 52.1 43.31 39.58 39.03 39.1 39.95 37.07 40.5 49.67 50.9 53.08 53.4 52.29 51.04 52.86 51.5
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1 54.55 53.91 54.76 54.7 54.23 54.32 55.54 55.98 55.93 50.54 50.16 50.92 50.25 47.47 42.92 49.01 51.92 52.89 55.94 54.64 54.19 54.41 55.96 55.39
Hour
12
11
10
9
8
7
6
5
4
3
2
1
Month
Figure 2. The average hourly energy prices ($/MWh) in 2030 under
the base scenario.
42
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
workplace during work hours and at separate homes during other times. For this study, we modeled a group of five
vehicles, each having a 60-kWh battery and a maximum
charging and discharging power of 6.6 kW. We assumed
that each vehicle has access to a V2G-capable EVSE at
both home and work.
The tool can model several VGI use cases. To create a
baseline for determining the value of optimized EV dispatch, an “unmanaged” charging profile is generated.
Under an unmanaged charging strategy, whenever an EV
plugs in, it is charged immediately at maximum power
until a full state of charge (SOC) is reached. Dispatch can
then be conducted in either V1G mode or V2G mode so
that the incremental benefits of these technologies can be
determined. V1G and V2G dispatch can be optimized from
the perspective of customers (e.g., to maximize their bill
savings) or from the utility’s perspective to minimize its
cost of supplying electricity, commonly known as the utility’s avoided cost. The charging and discharging dispatch
can also be cooptimized with the sale of frequency-regulation ancillary service (AS) to the grid.
A common concern about V2G technology is that discharging the vehicle’s battery will increase battery degradation, thus shortening its useful life for transportation.
To address these concerns, the optimization model can
penalize the discharge of energy from an EV’s battery
to the grid and also penalize the SOC for being outside
of a specified range. For this study, we chose penalties
based on EV battery cycle life and cost of replacement and
penalized states of charge outside the range of 30 to 95%.
V2G Dispatch Flexibility Creates
Advantages Over V1G
Optimized dispatches of EV charging and discharging created with the Solar + Storage tool demonstrate why V2G is
a much more flexible resource than V1G. Figure 1 shows
example optimized dispatches under V1G and V2G modes
for a single vehicle plugged into the grid for 23 h on a Saturday, making one late evening trip at 9 p.m. The utility
avoided costs represent a typical early summer day in the
future California electric grid when solar overgeneration
causes negative midday energy market prices and loads
are paid for their consumption. As shown in Figure 1, discharging in the morning leaves the V2G vehicle with more
available battery capacity for charging during the period of
negative avoided cost than the V1G vehicle. The V2G vehicle can then discharge some energy from its fully charged
battery in the high-value evening hours, either before or
after taking a trip. By absorbing excess solar generation
through charging, the load of the V1G vehicle creates a
benefit for the utility of US$0.06 on this day. However,
because the V2G vehicle is able to charge far more energy
than the V1G vehicle at midday and then discharge to the
grid at high-value times, it creates a benefit of US$1.96 for
the utility. These values are absolute and not relative to
other charging profiles.
12 42.92 43.35 44.12 45.57 45.58 45.32 42.94 45.15 45.34 36.75 28.5 27.39 27.29 30.21 34.07 40.56 45.41 46.2 44.24 43.77 42.25 42.73 44.7 43.41
–6.97 –2.71 25.09 38.58 44.28 44.17 43.9 43.09 45.52 47.51 48.79 44.3
–13
11 43.81 43.42 43.25 43.31 43.59 43.8 46.82 46.48 26.54 16.28 –3.5
54.4 71.15 79.24 67.13 56.06 52.97 48.31 48.79
30.41 43.01 44.4 64.91 82.78 75.45 60.48 62.87 62.23 51.45
2.4
7.74 –5.96 –7.01
9 54.22 52.46 49.61 46.7 47.38 48.33 49.81 35.89 20.28 12.84 –2.06 –6.09 –7.51 –3.49 25.09 37.51 48.83 78.91 75.23 63.94 64.11 58.06 57.81 54.96
10 47.01 46.9 45.81 45.12 43.01 44.49 52.31 42.04 13.29 –0.05 –22.96 –25.67 –25.85 –18.75 20.61 37.7
Month
8 52.62 52.21 52.34 51.59 51.12 51.25 48.87 36.59 21.26 19.6
28.47 37.61 43.38 53.65 69.86 64.66 54.89 51.13 52.89 47.58
6.7
0.28
7 46.48 47.44 47.84 47.89 47.8 48.79 42.31 34.5 20.17 18.27 17.55 9.41
6 39.43 38.03 38.68 38.62 38.63 38.04 34.96 28.01 16.61 –0.11 –8.55 –16.69 –21.32 –22.23 10.58 19.66 28.8 30.46 40.77 42.29 37.66 40.51 45.99 40.8
14.6 20.26 29.52 28.67 31.48 33.33 36.46 34.42
–30
–30
–30
–30
–30
31.4 30.43 31.19 31.2 29.66 30.89 26.57 19.79 0.58 –24.58 –30
5 30.01 30.01 28.27 26.91 26.39 24.63 25.4 10.12 –1.49 –13.75 –14.67 –24.44 –22.88 –16.91 –9.36 –1.57 23.03 23.42 33.48 30.48 30.85 36.8 42.87 34.74
4
–30 –17.12 25.71 32.14 33.55 34.93 34.57 35.03 36.99 37.17
–30
–30
3 37.14 37.94 37.91 37.52 36.71 36.01 34.59 35.18 15.95 0.53 –28.74 –30
40.26 39.33 39.75 40.02 40.79 42.3
41
20.5 20.27 24.99 35.29 41.22
2 42.19 42.86 44.01 44.42 44.9 44.32 44.58 43.22 38.69 26.16 –0.17 –7.78 –8.07 –8.56 –8.32 20.98 36.97 37.85 38.49 38.91 38.86 41.08 42.65 42.6
16
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Hour
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1
We considered two scenarios for evaluating VGI technologies: a base and a high-value scenario. The value streams
that change between the base and high-value scenarios
are energy and AS market prices, distribution network
capacity value, and generation capacity value. Unlike
other value streams in the study, AS revenues are not captured as an avoided cost but modeled as a service that can
be offered, subject to market and physical constraints.
Energy and AS market prices are based on California Public Utilities Commission (CPUC) Integrated Resources Planning (IRP) proceeding cases and are estimated using
production simulation. The base scenario aligns with the
CPUC IRP reference case, in which a roughly 50% renewable portfolio standard (RPS) is achieved by 2030. This
matches the 2030 goal of California’s recently adopted law,
Senate Bill 100. In our high-value case, the electric grid
achieves an 80% RPS by 2030.
The effects of increasing renewable penetration on
energy market prices are shown in Figures 2 and 3, with
red indicating negative energy prices and green indicating
high energy prices. In the high-value scenario, negative
midday energy prices are more pronounced throughout
the year. Energy prices are generally lower in the high-value scenario, with the exception of higher evening-time
energy prices in the fall. Because energy prices can be an
opportunity cost for providing AS, we believe that AS
market trends would follow energy market trends in the
high-value scenario, causing lower midday AS prices and
higher prices during fall evenings than under current
market conditions.
Generation capacity value is estimated for the base
and high-value scenarios using a net cost of new entry
calculation, assuming that a new combustion turbine
would be built to meet additional generation-peaking
capacity needs. The base scenario aligns more nearly
with current market conditions, where there is no
near-term need for additional generation capacity,
leading to values of US$76/kW-yr in 2018 and rising to
US$121/kW-yr in 2030. In the high-value scenario, we
17
Avoided Cost Value Streams
1 42.26 42.65 44.15 45.26 45.88 46.92 44.2 45.59 50.18 36.22 22.99 19.8
18
19
20
21
22
23
24
An EV with V2G also has an advantage in capturing
value during times with high energy prices or high generation and distribution capacity value. An EV with V2G will
fill its battery and prepare to discharge as much energy as
possible during times of high value, while an EV with V1G
can create value only by shifting coincidental charging
loads to off-peak times. From the dispatch results, we also
observe that, if a V1G vehicle rarely drives and thus consumes relatively little energy, there is less load that can be
shifted to periods of negative pricing and less value in
managing its charging load. Conversely, a V2G vehicle
that mostly sits unused for transportation offers more
scheduling flexibility and value to its utility as a DER than
does an EV that frequently requires large amounts of
energy for transportation.
Figure 3. The average hourly energy prices ($/MWh) in 2030 under
the high-value scenario.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
43
Unmanaged
Charging
Smart
Charging (V1G)
V2G
V2G With AS
Real Levelized Cost (US$/Yr/EV)
600
400
200
0
US$313
US$243
–US$94
–200
–US$248
–400
Costs
Net
and
Value
Benefits
Costs
Net
and
Value
Benefits
Costs
Net
and
Value
Benefits
Costs
Net
and
Value
Benefits
CO2 Cost System Energy Cost
Net Benefit Net Cost ASs
RPS Cost
Distribution Capacity Transmission Capacity Generation Capacity
Figure 4. The levelized costs and benefits for the base scenario under the utility’s control. CO2: carbon dioxide.
assume that 2018 is the resource balance year, giving
values of US$124/kW-yr in 2018 and increasing to
US$144/kW-yr in 2030. Given recent approvals by the
CPUC for energy storage projects, it is possible that,
in the near future, a zero-emissions resource such as
battery energy storage may be a more appropriate reference resource with a much greater avoided cost for
generation capacity.
Although distribution network capacity can be very valuable, the value is very location specific, and the opportunities
to defer distribution upgrades with DERs can be limited.
Based on an analysis of distribution avoided costs filed with
the CPUC, we chose distribution capacity values of US$20/
kW-yr and US$120/kW-yr for the base and high-value scenarios, respectively, with the high-value scenario representing a capacity-constrained area in Southern California.
V2G Delivers Value Over V1G
Our modeling indicates that V2G technology can transform
an EV from a load the utility incurs a cost to serve into a
DER that creates significant benefits. The total cost/benefit
and the avoided cost component value streams are shown
for several VGI use cases in Figures 4 and 5 for the base and
high-value scenarios, respectively. These figures suggest the
costs for and benefits to the utility from serving and managing a group of five EVs in different use cases on a levelized per-vehicle, per-year basis. Generation capacity,
distribution capacity, and AS are the most significant value
streams captured.
When AS is not provided, there is an energy value
stream benefit; however, when AS is provided, energy
44
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
costs are incurred to enable greater participation in AS
markets. In the high-value scenario, the ability to provide
AS adds little benefit over load shifting with V2G. We also
studied a sensitivity case in the high-value scenario,
where the model’s constraints and penalties for reducing battery degradation are removed. In that case, the
total benefit rose by US$359/vehicle/yr along with the
annual energy discharged, from 10,225 kWh/vehicle/yr
to 15,051 kWh/vehicle/yr.
The incremental values of V1G and V2G technologies
are shown in Table 1 for the different scenarios and use
cases. The table also includes the annual energy discharged per vehicle with V2G.
Realizing the Value of V2G
The results of our modeling indicate that it will be most
advantageous to deploy V2G technology in generation and
distribution capacity-constrained locations, where the
value of V2G can be more than four times that of V1G. If
energy storage becomes the preferred generation capacity
resource, then all of the dollar values presented in Table 1
will be even greater. When automakers design V2G systems
as a feature on vehicles, they must be convinced that any
additional battery wear and tear will be outweighed by the
V2G benefits for the vehicle owner. Our modeling shows
that relaxing the limits on discharging the battery would
increase the electric grid value of V2G by 32%, although the
energy discharged would also increase by 47%.
There are challenges that must be overcome before consumers can access the large potential value streams of distribution capacity and AS. There may be only a few locations
1,600
Smart
Charging (V1G)
Unmanaged
Charging
V2G
V2G With AS
Unconstrained
V2G With AS
US$1,380
Real Levelized Cost (US$/Yr/EV)
1,400
1,200
US$1,021
US$1,005
1,000
800
600
400
200
0
–US$92
–200
–400
–US$345
Costs
Net
and
Value
Benefits
Costs
Net
and
Value
Benefits
Costs
Net
and
Value
Benefits
Costs Net
and Value
Benefits
Costs
Net
and Value
Benefits
CO2 Cost
Net Benefit Net Cost ASs RPS Cost
System Energy Cost
Distribution Capacity Transmission Capacity Generation Capacity
Figure 5. The levelized costs and benefits for the high-value scenario under the utility’s control. CO2: carbon dioxide.
TABLE 1. A summary of incremental benefits and discharged energy for VGI use
cases (average per vehicle).
Scenario
AS Provided
with V2G?
V1G Versus
Unmanaged (US$)
V2G Versus
V1G (US$)
Energy Discharged
(kWh)
Unconstrained high value
Yes
253
1,472
15,051
High value
Yes
253
1,113
10,225
High value
No
253
1,097
7,969
Base
Yes
154
407
9,454
Base
No
154
337
6,322
Note: The incremental benefits are in terms of the utility’s costs and benefits of serving EV charging. The incremental costs associated with equipment and enabling technology are not included
in this calculation.
with significant distribution value, and VGI remains unproven as a reliable resource for distribution planning. We also
see that the small, incremental benefit of providing AS
instead of performing load shifting with V2G may not be
worth the cost of the expensive communications and
equipment necessary to participate in today’s AS markets.
When industry is ready to adopt V2G, it must develop new
business models and vehicle warrantees that share these
costs, benefits, and risks of V2G among automakers, vehicle
owners, utilities, and VGI service providers.
Acknowledgments
A portion of this work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory, California, under contract
DE-AC52-07NA27344. This work was funded in part by
the CEC under agreement EPC-14-086.
Biographies
Jonathan Donadee ([email protected]) is with Lawrence
Livermore National Laboratory, Livermore, California.
Robbie Shaw ([email protected]) is with Energy and
Environmental Economics, Inc., San Francisco, California.
Oliver Garnett ([email protected]) is with Energy and
Environmental Economics, Inc., San Francisco, California.
Eric Cutter ([email protected]) is with Energy and Environmental Economics, Inc., San Francisco, California.
Liang Min ([email protected]) is with Lawrence Livermore
National Laboratory, Livermore, California.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
45
By Jonathan Coignard, Pamela MacDougall,
Franz Stadtmueller, and Evangelos Vrettos
Will Electric
Vehicles Drive
Distribution Grid
Upgrades?
The case of California.
HE FINITE NATURE OF FOSSIL FUELS, THE
effects of climate change, and concerns
about air-quality issues are each stimulating initiatives in many sectors of the economy to reduce the amount of carbon dioxide
pouring into the atmosphere. Much attention is focusing
on the transportation sector, an especially large contributor
of greenhouse gas emissions. According to the Intergovernmental Panel on Climate Change, approximately 23% of
T
total energy-related carbon dioxide emissions come from
vehicles. The widespread push for alternatives to gasolinepowered vehicles has led to cumulative sales of more than
4 million electric vehicles (EVs) worldwide. In California,
cumulative sales of EVs passed 500,000 in November 2018.
The shift to EVs in California is taking place at the same
time that use of renewable energy sources is emerging.
Renewables now represent 34% of retail electricity sales in
the state, which has set an ambitious target of 100%
Digital Object Identifier 10.1109/MELE.2019.2908794
Date of publication: 11 June 2019
46
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
2325-5987/19©2019IEEE
Grid Considerations for
Large-Scale EV Integration
In August 2018, one of every 10 new vehicle purchases in
California was an EV. As EV adoption has implications for
power systems, we discuss the challenges for the distribution grid and what is currently being done by utilities to
prepare for the electrification of passenger vehicles.
Characteristics of EV Load Demand
At a macro scale, EVs appear to pose only a modest burden on the electric grid. The California Energy Commission estimates that 3.9 million EVs could add 15,500 GWh
of energy demand, equivalent to just 5% of California’s
current total annual energy demand. However, at a micro
scale, EVs represent a significant addition to traditional household loads. In 2018, PG&E recorded that the
average peak demand—the aggregate demand from residential customers divided by the number of customers—was approximately 1 kW/household (the 1 kW
value includes the natural power smoothing across several customers and does not reflect the maximum
instantaneous peak demand at the household level). By
comparison, most EVs commonly charge at 6.6 kW with
a level 2 charger. At an average of 37 mi driven per day,
an EV in the United States consumes approximately
10 kWh/day, which is a significant portion of the 17.5 kWh
of average daily household consumption in California. A
typical EV charging period at residential locations starts
between 4 and 7 p.m. and coincides with the grid peak
demand observed around 8 p.m. Therefore, in terms of
energy consumption and power demand, an additional
level 2 residential charging station is similar to an additional house on the grid.
In terms of geographical distribution and density, EV
adoption is not expected to be evenly distributed across
all distribution grids. On the contrary, EVs are typically
found in clusters, as demographics and peer pressure are
key factors when buying an EV. Some disparities will exist
regionally. For instance, the National Renewable Energy
Laboratory (NREL) map of EV density shows that the
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
©ISTOCKPHOTO.COM/LYUDINKA, CALIFORNIA MAP— ©ISTOCKPHOTO.COM/FRANKRAMSPOTT, PALM TREE—IMAGE LICENSED BY INGRAM PUBLISHING
penetration of renewable energy sources by 2045. Both
trends are creating challenges for distribution grids, which
traditionally have been designed to incorporate a number of
large power plants connected to the transmission network to
serve a predictable aggregated load made up of many small
customers. The rise of distributed energy resources (DERs),
such as fast-charging stations for EVs and solar panels, is disrupting the predictability and homogeneity of distribution
grids. As a result, it is necessary to evaluate grid planning,
operation, reliability, and rate plans/tariffs.
This article discusses how the distribution grid infrastructure can be adapted to accommodate the electrification of passenger vehicles. We show the impact of
uncontrolled EV charging on 39 real-world distribution feeders in Northern California and then extrapolate the results
for a larger set of more than 1,000 residential feeders within
the service area of the Pacific Gas and Electric Company
(PG&E). Our objective is to determine what, if any, special
requirements are needed to accommodate EV loads and
whether charging stations can be installed within the existing network without additional direct control structures or
indirect control mechanisms, such as economic incentives.
We provide recommendations for reducing the costs associated with adapting the distribution grid for demands related
to the shift to EVs. Although many scientific papers have
included impact analyses about EV integration, they often
use prototypical feeder models and synthetic data as the
input for simulations. We believe that investigations using
actual distribution feeder models from regular utility operations can provide more realistic results and better inform
strategic investment and planning decisions.
47
In terms of
geographical
distribution and
density, EV adoption
is not expected to
be evenly distributed
across all
distribution grids.
density of EVs in San Francisco is 20
times greater than that in Sacramento. As most EVs are purchased by
higher-income households, disparities might also appear between
neighborhoods, which means that
higher-income neighborhoods will
likely reach an EV penetration of
100% or higher before other neighborhoods. Note, however, that EV
adoption could become more homogenous as supplies increase and prices
fall. As California ramps up to its goal
of 5 million EVs by 2030, a new charging infrastructure is already being
installed at workplaces, residential
areas, parking lots, and other public places. In fact, various databases, such as Plugshare and OpenChargeMap,
are now available to track the charging infrastructure and
keep EV drivers informed. In this new situation, utilities
need to take into account plans for charging infrastructures and analyze the expected impact of uncontrolled EV
charging on the distribution grid.
Characteristics of the Distribution Grid
Distribution grid planning is needed to determine the
investments required to ensure a reliable power supply
within network constraints. EVs have the potential to
disrupt the grid. To prevent that from happening, plans
need to be made now for widespread EV integration. As
more DERs are added on the network, distribution grid
planning becomes more complex. With weather conditions affecting renewable energy sources, daily weather
forecasts need to be considered. Also, the state of charge
for batteries and sudden load variations from EVs have
to be incorporated into plans. While tools exist to simulate individual components of the power system [transmission grids, distribution grids, photovoltaics (PVs),
buildings, communication infrastructure, and EVs], few
frameworks are available to enable holistic power system
cosimulation. Therefore, improved tools for distribution
grid planning could help to better measure the required
capacity margin for feeders in the presence of significant
Feeders (%)
20
Median Capacity
Margin: 3.1 MW
15
Distribution Grid Reinforcement
and Associated Costs
10
5
0
0
1
2
3
4
5
6
7
8
Feeder Capacity margins (MW)
9
10
Figure 1. The capacity margin in megawatts for more than 3,000
feeders in PG&E’s territory in 2017.
48
variable generation and load units,
such as EVs.
To allow for traditional load
growth, distribution grids are built
with some capacity margin. In this
study, we had access to a database of
3,000 distribution feeders in PG&E’s
service area and estimated the available capacity margin for each feeder
(Figure 1). Overall, the available capacity margin for 50% of the 3,000 feeders
is less than 3.1 MW. While this margin
is large enough for traditional peakload growth, it might not be sufficient
to accommodate the higher power
consumption of EV chargers. For
instance, if all stations are in use, 50% of the feeders could
host, at most, only 25 dc fast chargers (rated at 120 kW) or
470 smaller level 2 chargers (rated at 6.6 kW).
As the energy demand from charging stations follows
the geographically uneven adoption of EVs, some feeders
might have high EV penetrations, while others could
experience no or negligible additional power demand
from EVs. The higher power requirement of fast-charging
EVs, the potential clustering of EVs on the same feeder,
and their distance from the feeder head all affect the
grid. As a result, medium- and low-voltage networks in
their current state might not reliably support high EV
penetration. In general, distribution grids could encounter undervoltages and currents exceeding transformer
and line power ratings, harmonics, and phase imbalances. These effects could reduce reliability, increase power
losses, and lower margins for future load growth, which
will result in a cost for both utilities and customers. Fortunately, utilities regularly perform long-term load forecasting, taking into account the adoption of EVs and the
resulting impact on the system, while prioritizing capital
investments to maintain adequate capacity. To ensure
grid reliability, simulation tools need to adequately represent the stochasticity of EV demand and offer potential
control strategies. Addressing this rapid load growth, utilities can take a number of actions, including reinforcing
the grid with additional lines and transformers, adding
local stationary storage, incentivizing off-peak consumption with time-of-use (TOU) rates, and developing ecosystems for grid assets (such as EVs) to provide
distribution grid services.
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
Utilities are regulated monopolies with a strong incentive
to promote grid reinforcement, as they are directly remunerated for their investments. In this context, the grid
could be reinforced for the theoretical worst-case scenario
where all EVs charge at the same time during peak hours,
therefore justifying expenditures for additional lines,
TOU rates are the
most popular form
of time-varying rates
for both EV and
non-EV customers.
transformers, capacitor banks and/or
voltage regulators for voltage support,
and stationary storage. Table 1 provides the estimated costs for different
grid reinforcement measures. These
estimates must be considered with
caution because they vary significantly from country to country. Still, they
illustrate the order of magnitude of
the required expenditure.
Even though grid reinforcement is the traditional way
utilities deal with anticipated load growth, it is not necessarily the only way to manage the peak-demand increase
from EVs. Other measures include the use of advanced
distribution management systems and the deployment of
smart EV chargers with price signals to properly manage
EV charging and shift the demand to times when the grid
is under less stress. Measures based on TOU rates are discussed in the next section.
Financial Incentives Through TOU Retail Rates
Standard, fixed-price electricity rates do little to encourage
EV adoption or optimize charging times. In fact, such rates
may even discourage efficient charging practices because
customers are apt to charge when it is most convenient to
them rather than when it is most beneficial to the grid. In
contrast, time‐varying rates convey price signals that better reflect the cost of producing and delivering energy at
different hours. Time‐varying rates include TOU rates, critical peak pricing, peak time rebates, and dynamic hourly
pricing. In addition, some utility rates include a demand
charge, which is typically based on a customer’s maximum power demand during a month.
TOU rates are the most popular form of time‐varying
rates for both EV and non-EV customers. To avoid increases in peak demands, large utilities in California offer retail
rates that encourage residential customers to charge their
EVs during off-peak hours, namely between 11 p.m. and
7 a.m. For example, PG&E offers TOU tariffs nonspecific to
EVs and two EV-specific rate plans for
residential customers, one combining
EV and household consumption and
the other separating the two and
using a dedicated metering system.
PG&E has enrolled 45,000 customers
in EV rate plans, which accounts for
25–30% of the registered EVs in PG&E’s
territory. The current off-peak rate for
electricity is US$0.13/kWh, which is
equivalent to approximately US$1.30/gallon of gasoline.
This enables EV drivers to save a significant amount of
money, as current gasoline prices are around US$3.50/gallon. Hence, PG&E estimated that 80% of EV charging is
done during off-peak hours. Furthermore, customers on
EV rates consumed 10–25% less energy at peak hours
compared to standard residential consumers in PG&E’s
territory. Although this might be the result of a small
number of already informed consumers, EVs have the
potential to influence consumption patterns toward more
grid-friendly behavior simply by educating and sending
price signals to consumers. Because managing peak
demand is a key challenge for electric utilities, they need
to provide EV customers with clear electricity price signals
to encourage charging during off‐peak periods. Electric
utilities can achieve high levels of customer enrollment by
defaulting customers onto an appropriate rate (through an
opt‐out design).
EVs as an Opportunity for the Grid
While studies have highlighted how integrating EVs in the
distribution grid affects operations, other studies have
also suggested using the flexibility of EVs to provide services to transmission system operators, utilities, and
renewable energy plants. EVs should not be considered
merely passive loads. Thanks to their energy-storage capabilities, EVs have the potential to provide services beyond
transportation, and these services can go beyond standard
TOU rates. EVs, generally idle more than 90% of the day
TABLE 1. The estimated capital cost for lines, cables, transformers, capacitor banks,
and stationary storage systems from a European study.
Components
Estimated Capital Cost
Medium-voltage overhead lines/cables
US$115,000–US$230,000/km
Low-voltage cables
US$80,000–US$115,000/km
Low-voltage overhead lines
US$35,000–US$75,000/km
Ground-mounted medium/low-voltage transformer
US$16,000–US$40,000
Pole-mounted medium/low-voltage transformer
US$6,000
High/medium-voltage transformer
US$2,000,000–US$6,000,000
Capacitor banks, fixed and switched
US$20,000–US$50,000/MVA reactive
Stationary storage
US$650/kWh
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
49
Standard, fixed-price
electricity rates do
little to encourage EV
adoption or optimize
charging times.
and with a high degree of flexibility,
are quick-response units with the
potential to offer bidirectional power
flow, known as a vehicle-to-grid (V2G)
function. Studies have estimated that
EVs could provide active and reactive
power support as well as renewable
energy integration support. Through
active power support roles, EVs can
help manage congestion, reduce
power losses, shift loads, shave peaks, fill valleys, and control voltages (voltage control through active power management is more relevant for distribution grids with lower
nominal voltages due to the higher line reactance/line
resistance ratios of distribution lines.) Reactive power support comes in the form of reactive power compensation
(injection or absorption) to regulate voltage profiles and/or
minimize reactive power losses. Renewable energy support is typically in the form of capacity firming to compensate for the intermittent nature of wind and solar
power generation. As experimentally validated in a field
trial at the Los Angeles Air Force Base, V2G could also provide ancillary services, which are becoming more important as synchronous generators are replaced with
inverter-based generation on bulk electric systems.
Although these value streams are typically for larger
customers (workplaces and parking lots, for example),
they might also be accessible to residential customers via
aggregators. Some prototypical projects to enlarge the
type of services provided by EVs already exist. In the case
of ancillary services, the field trial project at the Los
Angeles Air Force Base found a theoretical profit of
US$70/month/vehicle. However, in practice, the project
recorded net losses due to additional fees from participating in the market. The ancillary service market is a
small fraction of the energy market. Therefore, it is
exposed to saturation effects. In 2018,
eMotorWerks, a company selling connected EV chargers, mobilized 6,000
chargers corresponding to 30 and
70 MWh virtual batteries to participate in the California Independent
System Operator’s demand-response
market. Both of these examples represent services provided at the transmission level. As of today, there are
few demonstration projects and field tests to coordinate
EVs for the provision of distribution grid services. Two
examples are the EcoGrid EU project, funded by the European Union, and the Nikola project, funded by the Danish ForskEL R&D program. The Technical University of
Denmark is involved in both demonstrations.
While some utilities and states (especially California)
invest in programs to ease the transition to an electrified
transportation sector, this is not necessarily the case
across the United States and among smaller utilities. A
recent survey of 486 utilities (Smart Electric Power Alliance, 2018) states that nearly 75% of the utilities were in
the early stages of planning for EV market growth. Furthermore, regulatory uncertainties make replicating EV
programs between states and utility territories difficult.
Therefore, collaboration will be essential for widespread
deployment of EVs.
Methodology for Impact Analysis
and Case Study
This study evaluates the impact of large EV penetration on
distribution grids from the PG&E service area in a future
scenario where each household has one EV. Typically, for
residential feeders, 4,000–8,000 EVs were added according
to the total number of households on each feeder (Figure 2).
The scenario assumes that 50% of the vehicles have access
38
8k
36
Number of EVs
32
6k
28
26
25
4k
19
2k
11
9
4
6
5
2
15
12
14
13
8
3
18
34
33
24
22
17
16
21
37
35
31
27
23
7
30
29
20
10
1
0
0
2k
4k
6k
8k
10 k
Feeder Peak Demand (kW)
12 k
14 k
Figure 2. A graph showing the number of EVs added per feeder as a function of the feeder’s peak demand. Each feeder is represented by a blue
dot. The dashed red line indicates where y = x.
50
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
to a level 2 charger (6.6 kW) at work,
and 50% of home chargers are level 2,
the rest being traditional outlets
(1.4 kW). The impact of the additional
load demand from EVs is measured in
terms of voltage deviation from the
nominal value, increased line loadings, and remaining feeder capacity.
The objective of this analysis is to determine whether
measures are needed to accommodate EV loads and
whether charging stations can be installed on existing
networks without additional control structures or economic incentives.
The methodology developed is practical and inspired
by similar investigations performed by PG&E for interconnection planning (Figure 3). At the feeder level, we
used a detailed topology, including electrical characteristics for each component, as well as the location and average energy demand for each customer. The historical
measurements from the supervisory control and data
acquisition (SCADA) system give hourly active and reactive power demand at the feeder head. Using historical
measurements and the known grid topology, we ran
power-flow analyses using CYMDIST commercial software, which is widely used by many electric utilities in
the United States. A number of EVs were added at each
node based on the number of connected residential customers, and subsequent power flows were run incorporating EV charging profiles. The power-flow results with
and without EVs were then compared to quantify the
impact of EVs on the grid.
EVs should not be
considered merely
passive loads.
Detailed Feeder Models
In California, and more specifically in
PG&E’s territory, the capacities of the
distribution grids typically range from
less than 1 to 25 MW with a nominal
voltage of 12 kV, although some networks have a nominal voltage of 4 or
21 kV. Networks are usually constructed with a meshed topology, but they operate radially and
can be reconfigured during scheduled and unscheduled
outages. While significant parts of the grid are wired with
three phases, the edge of the grids can be wired with two
phases or even one phase and the neutral.
For this analysis, 39 feeders with different topologies,
customer breakdowns, and historical demand profiles
were studied. The feeders are connected to eight different
substations, as shown in Figure 3. The 39 detailed feeder
models are representative of the larger PG&E territory in
terms of design, capacity, and nominal voltage. Half of the
feeders serve mainly residential customers, while the rest
serve a mix of industrial, commercial, agricultural, and
special load customers. Feeder lengths vary from 2 to
64 km, with 68% of the feeders under 10 km; 56% of the
feeders have a nominal voltage at 12 kV. The historical
demand profiles from 2016 reveal that 80% of the feeders
have a peak demand between 3 and 15 MW.
EV Load Demand
To include EVs in power-flow analysis, spatial and temporal aspects of EV charging power demand must be considered. The spatial distribution of EVs is readily obtained
Feeder Head
1) Historical active
and reactive power
demand is imposed.
Substations Include 3–12 Feeders
2) One EV is added
for each household
at each node.
3) We run a power flow
analysis before and
after the EVs.
Substations
(a)
(b)
Figure 3. (a) The locations of the substations used in this analysis. (b) An example of feeder topology and the main steps of the methodology.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
51
Low
Mid
High
150
100
50
0
0
:0
21
0
:0
18
:0
0
15
:0
0
16 June 2017
12
0
:0
09
:0
0
:0
06
00
:0
0
0
03
Power Demand (kW)
based on the assumption of one EV per household and
known information on residential house connections at
each node. To determine the temporal demand from EVs,
various load shapes for 100 EVs charging at home were
simulated under different scenarios (Figure 4). The load
profiles are based on 2,952 full-day vehicle itineraries from
the National Household Travel Survey of 2009 in California.
The itineraries define when, how far, and to which location vehicles are traveling, enabling estimation of on-road
energy consumption and state of charge during the day.
EV on-road consumption is derived from the V2Gsim powertrain model developed at the Lawrence Berkeley National Laboratory.
Time
Figure 4. An EV load profile at residential locations for 100 EVs for
Power-Flow Analysis
20
After EVs
Before EVs
15
10
18 December
2016
Time
0
0
:0
00
:0
21
0
:0
18
0
15
:0
0
:0
12
0
:0
09
0
:0
06
:0
03
:0
00
0
5
0
Feeder
Power Demand (MW)
low-demand (low; blue), middle-demand (mid; orange), and highdemand (high; green) scenarios.
19 December
2016
Figure 5. The historical load shape from SCADA measurements
EV Load Demand (kW)
(blue) and the load shape with additional EVs and PVs (orange).
600
400
200
0
1 2 3 4
5 6 7 8 9 10 11 12 13 14 15
Distance (km)
Figure 6. An example of the spatial distribution of the EV load
demand at the peak time for a feeder. The load demand is summed
over intervals of 0.5 km.
52
Multiple scenarios were explored with respect to
where EVs charge and which type of charger they use.
Specifically, EVs could charge at workplaces, public places, or at home with chargers ranging from 1.4 (traditional
outlet) to 120 kW (dedicated dc fast charger). Different
scenarios (low, middle, and high demand) were analyzed
with varying numbers of vehicles charging at workplaces
and varying percentages of level 2 chargers (6.6 kW) at
residential locations (Figure 4). In all scenarios, if a charger is available, EVs start charging as soon as they arrive
at their destination without any control. In the most
aggressive scenario (high), EVs only charge at home with
a level 2 charger, leading to a significant peak demand of
175 kW. Meanwhile, in the low-demand scenario, all EVs
have access to a charger at their workplaces and have
only a traditional outlet at home (1.4 kW), thus leading to
a smaller peak demand of 68 kW. The middle-demand
scenario is constructed by assuming that 50% of the
vehicles charge at work and that 50% of the chargers at
home locations are 6.6-kW level 2 chargers (the rest
being traditional outlets). This scenario leads to a peak
demand at residential locations of 100 kW, which occurs
around 6:30 p.m. Although the high-demand scenario
could theoretically lead to a 660-kW peak demand (100
times 6.6 kW), the impact of level 2 chargers on peak
demand is not as dramatic because not all EVs arrive at
the same time and require only 51 min, on average, to
charge (23 mi traveled per day).
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
On the distribution grid side, the historical SCADA data of
active power at the feeder head were selected for four
days when the feeder approaches its maximal loading,
between 3 p.m. and 11 p.m. This ensures that the days
simulated are representative of the maximum evening
peak demand and therefore potentially lead to the highest
annual voltage deviation and line loading when correlated
with residential EV load demand. On the days selected,
the historical load demand is enforced at the feeder head,
hence setting different loading conditions as time progresses. In addition, a load-allocation method was used to
proportionally vary individual load connections based on
their known energy demand, such that the aggregate load
demand across all nodes matches the load demand historically recorded at the feeder head. This process results
in time-varying power injection of data for each node into
the grid model and for each time step.
One EV is connected per household, so the EV load
demand is added to the historic SCADA demand based on
the number of residential consumers at a node (Figure 5).
Due to the known information on the number of households at each node, EVs not only have a temporal dimension, as reflected by the load shape of Figure 4, but also a
spatial dimension within the grid, as shown in Figure 6.
PVs were also added to cover 25% of the feeder’s annual
energy need (both before and after adding EVs). PV power
output on the days simulated is based on feeder-specific
solar irradiance data from the NREL solar irradiance database. Although PVs provide additional generation during
the day, they do not assist in meeting the evening peak
demand due to time separation. Therefore, regardless of
their penetration, PVs do not affect the results obtained
with uncontrolled EVs.
Power-flow simulations were run with a 30-min time
step for the four days with the highest evening peak
demand for each of the 39 feeders. At each time step,
various simulation results were saved, including results
related to nodal voltages, line loading, and power
demand at the feeder head. Figure 7 provides instances
of results for each node of one feeder as a function of
distance from the feeder head, including the voltage and
line-loading profiles of that feeder. Each of the plots
presents two scenarios: the first scenario is without EVs
(blue), and the second scenario is with one EV per
household (orange). The voltage profile shows that one
branch of the network is significantly affected by EV
demand, with some nodes below 95% of the nominal
voltage. In contrast, another branch has a higher voltage
with EVs (around 9 km) due to the higher setting of a
tap-changing transformer. The line-loading profile
shows that some lines are above their maximal capacity,
especially as we get closer to the feeder head. Such
results are collected individually for each feeder and
day; they are then aggregated to the statistical results
presented in the next section.
Power-Flow Analysis Results and Discussion
The objective of this analysis is to determine whether a
scenario with one EV per household will require specific
attention and whether charging stations can be installed
within the existing network without additional direct
control structures or indirect control mechanisms based
on economic incentives. The scenario selected for the following results assumes that 50% of the EVs have access to
level 2 chargers at workplaces and that only 50% of households are equipped with level 2 chargers, with the rest
only using traditional outlets.
Results Before and After Adding Uncontrolled
EVs in 39 Feeders
The impact of EVs is measured with three metrics: the
remaining power capacity at the feeder head (defined as the
current maximum peak demand minus the projected peak
demand with the additional EV demand), the lowest
observed nodal voltage, and the highest observed line loading. Figures 8–10 show the respective results for the 39 feeders before and after adding one EV per household. For 19 of
the 39 feeders, residences consumed more than 50% of the
energy. We refer to those feeders as residential feeders.
Among the residential feeders, when one EV per
household is added, 58% of the feeders exceed their
remaining power capacity, 16% are below the 0.95-p.u.
voltage limit, and 47% have some line overloading,
which indicates that line-overloading problems are
more likely to be the limiting factor. Overall, 68% of the
feeders with residential energy consumption accounting for at least 50% of total energy demand (13 feeders
from the set of 19 feeders) are violating their maximum feeder head capacity, voltage limit, or line-loading limit. On average for the residential feeders, EVs
increase the projected peak demand by 64%, decrease
the lowest nodal voltage by 0.02 p.u., and increase the
highest line loading by 40%. These impacts lead residential feeders to have, on average, −0.21 MW of
remaining capacity, 0.98 p.u. for the lowest voltage,
and 99% for the highest line loading.
Based on 39 feeders, our results clearly suggest that the
middle-demand scenario with one EV per household
1.06
160
Before EVs
1.04
After EVs
140
Line Loading (%)
Voltage (p.u.)
120
1.02
1
0.98
0.96
100
80
60
40
20
0.94
0
0
5
10
Distance (km)
(a)
15
0
5
10
Distance (km)
(b)
15
Figure 7. (a) A feeder voltage profile at the peak demand (6:30 p.m.) per unit (p.u.) of the nominal voltage. (b) The feeder line loading profile at
the peak demand in the percentage of the maximum line capacity.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
53
Remaining Capacity (MW)
15
3
10
3
13
2
1
0
5
7
11
810
6
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20
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25 30
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Residential Customers (%)
(a)
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0
36
35
33 34 37
31
24
17
0
28
27
29
23
22
38
32
20
40
60
Residential Customers (%)
(b)
80
Figure 8. The remaining capacity in megawatts for 39 feeders. (a) The feeders before adding the EV demand (blue) and (b) the same feeders
after adding one EV per household (orange).
Highest Line Loading (%)
160
140
24
18
14
22
17
120
100
18
14
22
24
80
60
4
1
0
2
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5 67
8 10
11
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9
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33
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3436
27 31
26
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25
32
1
0
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35 38
0
20
40
60
Residential Customers (%)
(a)
80
2
21
12
6
5 7 10
11
8
13
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19 20
15
29
3
3
20
31 33
37
28
34
26
30
27
36
32 35
25
38
23
0
20
40
60
Residential Customers (%)
(b)
80
Figure 9. The highest line loading in the percentage of the maximum line capacity for 39 feeders. (a) The feeders before adding the EV demand
(blue) and (b) the same feeders after adding one EV per household (orange).
Lowest Voltage (p.u.)
1.04
3
1.02
5 8
0
1
1
0.98
7
4
1213
910
6 11
19 21
20
14
15
2
16
17
18
24
22
23
7
19
13
34
3537
29
27
30
3
38
25
26 31
5
0
1
32
33
4
8
6
12
910
11
14
16
36
0.96
15 17
28
0.94
38
25
26
29 31
18
2
21
20
22
32
33
24
23
2730
34
35
37
36
0.92
28
0.9
0
20
40
60
Residential Customers (%)
(a)
80
0
20
40
60
Residential Customers (%)
(b)
80
Figure 10. Graphs showing the lowest nodal voltage per unit (p.u.) of the feeder head voltage for 39 feeders. (a) Feeders before adding the EV
demand (blue). (b) The same feeders after adding one EV per household (orange).
54
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
As shown in this
study, with one
EV per household,
60% of residential
feeders might
need some grid
reinforcement.
0.1
6
:0
0
12
:0
0
09
:0
0
06
:0
0
03
:0
0
00
:0
0
21
:0
0
4
3 January 2016
0.05
0
–10 –8
8
18
0.15
Mean Margin
Before EVs:
3.3 MW
12
10
:0
0
0.2
Mean Margin
After EVs:
–0.9 MW
Theoretical Impact From
Controlled EVs
14
15
0.25
theoretical scenario where the control
mechanism allows us to shift EV
demand to off-peak hours and regulate it to a constant value.
To investigate the value of direct control schemes or indirect control mechanisms based on economic incentives,
the possibility of shifting EV demand
to off-peak hours without creating a
new peak (or with minimizing the
magnitude of the newly created peak)
was studied. The previously uncontrolled EV demand was
shifted to between 6 p.m. and 6 a.m. while minimizing
peak demand (Figure 12).
This approach assumes perfect knowledge and control of the system. In reality, not all EVs will participate in
the same control mechanism, and a constant aggregate
EV power cannot be achieved due to forecast errors and
the possibility of packet losses and delays affecting communication systems. Nonetheless, this analysis provides
a theoretical result suggesting that, of 19 residential feeders, 11 are subject to a peak-demand increase even in the
fully controlled case (Figure 13). However, note that this
peak increase is limited to 27% of the current peak
demand in the worst case and to 8% on average for all
residential feeders. Clearly, this is significantly better
than the uncontrolled EV case, with a potentially 104%
peak-demand increase in the worst case and a 64%
increase on average. Moreover, perfect knowledge and
control of EV charging to minimize peak-demand
increase could enable feeders to remain below their
maximum capacity limit with no further reinforcement
Power Demand (MW)
Density Probability
Even though detailed voltage and
line-loading analyses for all PG&E
feeders are not possible due to limited distribution grid models and
SCADA data, the relative impact of
EVs on feeder capacity was extrapolated for 1,054 feeders in the San Francisco Bay area.
Based on available geographical coordinate information,
the feeders in this area are likely to be predominantly
residential (>50% of residential energy demand). The
average relative peak demand increase (64%) computed
for the 19 residential feeders was assumed to be representative of the larger feeder data set, and it was applied
for each of the 1,054 feeders. Figure 11 shows the impact
of the one-EV-per-household scenario on the remaining
capacity per feeder.
Based on the results, 60% of the feeders in the San Francisco Bay area would reach or exceed their maximum loading limit. Arguably, these generalized results should be
viewed with caution because of the simplifying assumptions made due to lack of detailed data. Nevertheless, the
results indicate again that the middle-demand scenario
with one EV per household requires specific control mechanisms or grid reinforcement so that the distribution grid
will not be disrupted by additional load demand from
uncontrolled EV charging. We estimate that, for the feeders
with no remaining capacity in the San Francisco Bay area,
28% of the EVs on average would need to charge off-peak
to ensure that 75% of the feeders do not exceed their maximum capacity threshold. In other words, 28% of the EVs
would need to follow TOU incentives to charge during offpeak times. In the next section, we provide results for a
:0
0
Uncontrolled EV Impact
on a Larger Data Set with
1,054 Feeders
12
requires control mechanisms or reinforcement on most residential distribution grids to ensure that they will
not exceed their maximum capacity.
4 January 2016
Time
–6 –4 –2 0
2
4
6
Feeder Capacity Margin (MW)
After EVs
8
10
Before EVs
Figure 11. The feeder capacity margin in megawatts for 1,054 feeders in the San Francisco Bay area before EVs (blue) and after EVs
(orange) are added.
SCADA + Controlled EVs
SCADA + Uncontrolled EVs
SCADA
Figure 12. The feeder’s historic load profile without EVs (blue), the
additional load demand from uncontrolled EVs (orange), and the additional load demand with controlled EVs (red) from 6 p.m. to 6 a.m. to
minimize peak demand.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
55
23
29
24
22
37
31
33
35
26
27
34
28
21
25
38
30
36
32
20
Peak
Demand Increase (%)
160
140
120
100
80
60
40
20
0
Feeder IDs
Feeder Limit
Uncontrolled EVs
Controlled EVs
Figure 13. The peak-demand increase for 19 residential feeders with
uncontrolled EVs (blue) and controlled EVs (orange). Red dots mark
the maximum increase possible with the existing grid infrastructure.
(as indicated by the red dots in Figure 13). Practically
speaking, some local grid reinforcement will be necessary
to ensure adequate capacity margin.
Reinforcing the grid with storage systems is also a way
to address the problem. This measure provides local support and also accommodates more use of renewable energy. PG&E is implementing stationary storage with 567-MW
capacity approved across four projects, including a 10-MW
aggregation of behind-the-meter batteries located at customer sites and connected to the distribution grid. Utilities
are also demonstrating DER management systems for
optimizing the use of such flexible resources.
Path Forward for EV Adoption
EVs are leading consumers to demand less gasoline and
more electricity. As they charge from the distribution
grid primarily at residential locations, uncontrolled EV
charging will likely increase peak demand, potentially
leading to a degradation in the reliability and quality of
the power supply. As shown in this study, with one EV
per household, 60% of residential feeders might need
some grid reinforcement. Traditionally, reinforcing the
grid has implied investment in new lines, transformers,
and capacitor banks to cover predictable loads. However,
this might prove costly when planning for the potential
worst-case scenario with synchronized EV charging.
Reinforcing the grid should be coupled with some sort of
EV demand management program. With perfect knowledge and control of EV charging parameters, peak
demand could be contained to an approximately 8%
average increase, as opposed to a 64% increase in the
uncontrolled case.
Large utilities in California are now able to encourage off-peak charging by providing EV customers with
electricity price signals through static TOU rates. On
average, shifting 28% of EVs to off-peak charging with
TOU rates would limit the peak-demand increase to
existing feeder capacity margins for most residential
feeders. Although static TOU rates have been successful, some concerns exist regarding their ability to
56
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
provide adequate incentives in more dynamic systems,
as well as the risks they bring to creating new peak
demands at the beginning of lower-priced off-peak
periods. In this context, new static TOU rate designs
need to be developed that enable demand management systems and coexist with options that accommodate greater flexibility.
As the spread of solar PVs and fast-charging EVs
makes power systems less predictable, forms of dynamic
pricing have been suggested to align real-time distribution grid conditions with economic incentives. While
some control strategies and business models exist at the
transmission-grid level, distribution grids are in the very
early stages of adopting dynamic pricing. The path forward for high EV penetration includes a combination of
innovations in TOU rate designs, long-term load forecasting to plan grid reinforcement, and a DER management
system with local dynamic price signals to optimize the
grid for EVs and other DERs.
For Further Reading
A. Allison and M. Whited, “Electric vehicles are not crashing
the grid: Lessons from California Synapse,” Synapse Energy
Economics, Nov. 2017. [Online]. Available: http://www.synapseenergy.com/sites/default/files/EVs-Not-Crashing-Grid17-025_0.pdf
K. Knezovic, M. Marinelli, A. Zecchino, P. B. Andersen, and
C. Traeholt, “Supporting involvement of electric vehicles in
distribution grids: Lowering the barriers for a proactive integration energy,” Energy, vol. 134, pp. 458–468, Sept. 2017.
N. B. Arias, S. Hashemi, P. B. Andersen, C. Træholt, and
R. Romero, “Distribution system services provided by electric
vehicles: Recent status, challenges, and future prospects,”
IEEE Trans. Intell. Transp. Syst., Jan. 2019. doi: 10.1109/
TITS.2018.2889439.
Smart Electric Power Alliance, “Utilities and electric
vehicles: Evolving to unlock grid value,” Mar. 2018. [Online].
Available: https://sepapower.org/resource/utilities-electricvehicles-evolving-unlock-grid-value/
J. Wamburu, S. Lee, P. Shenoy, and D. Irwin, “Analyzing distribution transformers at city scale and the impact of EVs
and storage,” in Proc. Ninth Int. Conf. Future Energy Systems,
2018, pp. 157–167.
Pacific Gas and Electric Company, “Smart grid annual
report,” 2018. [Online]. Available: https://www.pge.com/pge_
global/common/pdfs/safety/how-the-system-works/electricsystems/smart-grid/AnnualReport2018.pdf
Biographies
Jonathan Coignard ([email protected]) is with
Lawrence Berkeley National Laboratory, Berkeley, California.
Pamela MacDougall ([email protected]) is with
Lawrence Berkeley National Laboratory, Berkeley, California.
Franz Stadtmueller ([email protected]) is with Pacific Gas
and Electric Company, San Francisco, California.
Evangelos Vrettos ([email protected]) is with Lawrence
Berkeley National Laboratory, Berkeley, California.
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Advancing Smart City Technologies
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xx
sensors and intelligent electronic
devices
T
Digital Object Identifier 10.1109/MELE.2019.2908918
Date of publication: 11 June 2019
Technology Leaders
using preliminary charging stanxx
dards developed for heavy-duty
off-road vehicles and equipment
in the San Pedro Bay ports as a
springboard for pursuing statewide and federal adoption of standards to ensure consistent and
cost-effective charging requirements for all seaports.
Other elements include exploring
innovative charging options; accounting for how to manage increasing
loads associated with electrification
while achieving resiliency and energy
savings; and aligning the blueprint
with the California Public Utility Commission’s Integrated Resources Plan,
the California Independent System
Operator’s local capacity requirements process, and state transportation goals. Completing the blueprint
xx
communication networks and
cybersecurity
xx
systems integration
xx
intelligence and data analytics
xx
management and control plat-
forms.
Visit the IEEE Smart Cities website (https://smartcities.ieee.org/)
for the latest information on smart
city webinars and to access the
Smart Cities Resource Center.
The Fifth IEEE Annual International Smart Cities Conference (ISC2 2019)
will be held in Casablanca, Morocco,
14–17 October 2019. The theme of the
conference is “Frugality and Inclusion
Paving the Way Toward Future Smart
Sustainable Cities and Communities.”
The flagship conference sponsored by
IEEE Smart Cities, ISC2 2019 will bring
together policy makers, administrators, infrastructure operators, industry representatives, economists,
sociologists, academics, and other
researchers and practitioners to discuss and collaborate on issues related
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.org/ for more information.
(continued from page 11)
by June 2019 will allow the Port to
seek additional funding for plan
implementation and infrastructure.
The Deep Dive
Toward Zero Emissions
The Green Port Policy marked the Port’s
transition from regulatory compliance
to its game-changing pursuit of clean
air, water, soil, and sustainability programs. After the original CAAP was
adopted in 2006, early strategies
focused on incentives for participation
in voluntary programs, green practices
negotiated into leases, tariff requirements, and the ports’ joint Technology
Advancement Program (TAP).
The results have been dramatic:
DPM emissions have dropped 88%,
SOx has plummeted 97%, and NOx
has fallen 56% since 2005, according
to the Port’s 2017 Air Emissions Inventory. GHGs were not targeted in the
original CAAP, but the same strategies
resulted in an 18% reduction in GHGs
since 2005. All of this has occurred
while cargo increased by 12%.
TAP prototypes led to a number of
the breakthroughs incorporated into
today’s large-scale demonstrations.
The Port’s focus on cutting GHGs will
also aid in further reducing DPM, NOx,
and SOx emissions. Aiming high has
paid big dividends for the economy
and the environment and provides
ample opportunities to forge ahead
toward zero.
Biography
Heather Tomley (heather.tomley@
polb.com) is with the Port of Long
Beach, California.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
59
DAT E S A H E A D
2019
11– 14 J U N E
EEEIC/I&CPS Europe 2019: IEEE International Conference on
Environment and Electrical Engineering and 2019 IEEE
Industrial and Commercial Power Systems Europe, Genova,
Italy, https://www.eeeic.net/eeeic/
17– 20 J U N E
COMPEL 2019: 20th Workshop on Control and Modeling
for Power Electronics, Toronto, Ontario, Canada, https://
compel2019.org/
17– 21 J U N E
WoW 2019: IEEE PELS Workshop on Emerging Technologies:
Wireless Power Transfer, London, United Kingdom, http://
www.wpw2019.org/
19– 21 J U N E
ITEC 2019: IEEE Transportation Electrification Conference
and Expo, Novi, Michigan, United States, contact Rebecca
Krishnamurthy, [email protected], https://itecconf.com
23– 27 J U N E
PowerTech 2019: IEEE PowerTech Milan, Milan, Italy, contact
Prof. Federica Foiadelli, [email protected], http://
ieee-powertech.org/
4– 8 AU G U S T
GM 2019: IEEE PES General Meeting, Atlanta, Georgia, United
States, contact Matt Stryjewski, [email protected],
http://pes-gm.org/2019/
13– 16 AU G U S T
ESTS 2019: IEEE Electric Ship Technologies Symposium,
Arlington, Virginia, United States, contact Dr. Scott Sudhoff,
[email protected], https://ests19.mit.edu/
20– 23 AU G U S T
PowerAfrica 2019: IEEE PES/IAS PowerAfrica, Abuja, Nigeria, contact Tunde Salihu, [email protected], https://ieeepowerafrica.org/
60
2 7 –3 0 A UGUS T
SDEMPED 2019: IEEE 12th International Symposium on
Diagnostics for Electrical Machines, Power Electronics, and
Drives, Toulouse, France, http://www.sdemped2019.com/en/
index.html
2 –6 S E P TE MBE R
EPE’19 ECCE Europe 2019: 21st European Conference on
Power Electronics and Applications, Genova, Italy, http://
www.epe2019.com/
9 –1 0 S EP TEMBER
SLED 2019: IEEE 10th International Symposium on Sensorless Control for Electrical Drives, Torino, Italy, https://attend
.ieee.org/sled-2019/
1 5 –1 8 S E P TE MBE R
ISGT LA 2019: IEEE PES Innovative Smart Grid Technologies
Latin America, Gramado, Brazil, contact Gabriel Arguello,
[email protected], https://attend.ieee.org/isgt-2019/
2 9 S E P TE MBE R–2 OCTOBE R
ISGT Europe 2019: IEEE PES Innovative Smart Grid Technologies Europe, Bucharest, Romania, contact Prof. George Cristian Lazaroiu, [email protected], http://sites.ieee.org/
isgt-europe-2019/
2 9 S E P TE MBE R–3 OCTOBE R
ECCE 2019: IEEE Energy Conversion Congress and Exposition, Baltimore, Maryland, United States, http://www.ieeeecce.org/2019/
2 9 S E P TE MBE R–3 OCTOBE R
2019 IEEE Industry Applications Society Annual Meeting,
Baltimore, Maryland, United States, https://ias.ieee
.org/2019annualmeeting
For more information on upcoming conferences, please
visit the following websites:
IEEE Power & Energy Society: https://www.ieee-pes.org/
meetings-and-conferences/conference-calendar
22– 24 AU G U S T
IEEE Transportation Electrification Community: https://tec
.ieee.org/conferences-workshops
EATS 2019: AIAA/IEEE Electric Aircraft Technologies Symposium, Indianapolis, Indiana, United States, https://
propulsionenergy.aiaa.org/EATS/
IEEE Industry Applications Society: https://ias.ieee.org/
events-conferences/conference-schedule.html
Digital Object Identifier 10.1109/MELE.2019.2908915
Date of publication: 11 June 2019
IEEE Power Electronics Society: https://www.ieee-pels.org/
conferences
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
Viewpoint
(continued from page 64)
technologies with a low risk of
stranded investment by 2050).
SCE’s GHG abatement methodology assessed more than 40 key measures of clean energy technologies in
five main sectors:
1) transportation (electric, hydrogen
fuel cell, and natural-gas vehicles, among others)
2) electric power (large-scale
renewable generation, hydrogen
pipeline injection, biogas, and
so forth)
3) industrial [efficiencies in heating,
ventilation and air conditioning (HVAC), machine drive, and
so forth]
4) residential (efficiency in home
appliances, water and space heating electrification, heat-pump
water heaters, and air-source heat
pumps, among others)
5) commercial (water and space
heating electrification and efficiencies in ventilation, lighting,
and so forth).
SCE developed three scenarios to
achieve the 36 MMT of incremental
abatement (incentivized by California’s multisector cap-and-trade program): the renewable natural gas
(RNG) pathway, the hydrogen path-
way, and the clean power and electrification pathway.
Of these three deep, long-term
decarbonization scenarios, we determined that the clean power and electrification pathway is the optimal
combination of measures to achieve
the 2030 GHG goal (Table 1).
In the RNG pathway, less largescale renewable generation is
required because natural gas in
pipelines is substituted with RNG.
Excess renewable generation (mostly
wind and solar) is managed through
power-to-gas (PtG) conversion of
electric power into synthetic methane, with landfill capture and conversion as the main sources. An
important challenge to the RNG
pathway is that the commercialization of PtG technology is at a very
early stage of development, with a
limited number of pilot plants in
operation. Moreover, the price to
produce and potentially import significant amounts of RNG entails a
higher abatement cost.
In the hydrogen pathway, a
hydrogen-natural gas blend at 7%
hydrogen by volume is transported
over a natural gas pipeline network
for end uses. Excess renewable
generation (mostly wind and solar)
is managed through electrolysis to
produce hydrogen. An important
challenge to the hydrogen pathway
is the need to build hydrogen production facilities, which are not
currently present in California.
Moreover, hydrogen production is
energy intensive, and its potential
as grid-scale storage is limited, in
part, by its low round-trip efficiency.
The cost to produce and build the
infrastructure for hydrogen results
in the highest abatement cost of all
three pathways.
SCE’s Blueprint for Integrated
Electrification
The clean power and electrification
pathway focuses on three economic
sectors—electricity, transportation,
and buildings—and is defined by
three interdependent measures:
xx
80% carbon-free electricity
xx
more than 7 million electric vehicles (including light, medium,
and heavy duty)
xx
electrifying space and water
heating in almost one-third of
the state’s building stock.
As electricity becomes cleaner,
every electric vehicle and electric
TABLE 1. A comparison of decarbonization scenarios. (Source: Southern California Edison 2017a.)
Clean Power and
Electrification
RNG
Hydrogen (H2)
Carbon-free electric power
80%
60%
80%
Light-duty vehicles
7 million electric
vehicles
7 million electric
vehicles
2 million electric vehicles
4 million H2 vehicles
Medium-heavy-duty vehicles
21% of vehicles
electrified
12% of vehicles using
compressed natural gas
4% of heavy-duty vehicles
using H2
Commercial and residential
Up to 30%
electrification
42% of natural gas
replaced by RNG
7% of natural gas replaced
by H2
Average abatement cost (180 MMT)
US$37/MT
US$47/MT
US$70/MT
Incremental abatement cost
(last 36 MMT)
US$79/MT
US$137/MT
US$262/MT
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
61
VIEWPOINT
space and water heater becomes
cleaner over its lifespan.
Decarbonize the Grid
If the energy produced in California
by large-scale resources is 80% carbon-free and energy efficiency and
distributed solar are maximized,
GHG emissions will be reduced from
84 MMT/year to 28 MMT/year, or
31.1% of the 2030 GHG reduction goal
(Figure 1). Supplying 80% carbon-free
energy would require a state generation portfolio comprising nondispatchable resources, including
wind and solar, and dispatchable
resources, including hydroelectric
generators, as well as the addition of
up to 30 GW of renewable capacity.
SCE plans to integrate the resulting
high penetration of large-scale
renewable resources by diversifying
the anticipated renewables portfolio
in terms of resource availability and
location, increasing the capacity of
the transmission grid, and enhancing
the integration across the Western
Interconnection (one of the two
major ac power grids in the continental U.S. power transmission grid).
Under the clean power and electrification scenario, as many as
10 GW of energy storage from fixed
and transportable sources will be
required to help manage the volatility and uncertainty of nondispatchable resources, such as wind and
solar, by providing energy balancing
on hourly, daily, and seasonal bases.
The challenges faced by California
today, including the “duck curve,”
i.e., the difference between electricity demand and the amount of
available solar generation throughout the day, can be mitigated by
adding energy storage at scale and
enabling load shifting with electric
vehicles. SCE expects these challenges to be exacerbated by the
addition of more nondispatchable
renewables to the system; thus,
gas-fired generation and hybrid
systems, such as peaker plants that
combine battery energy storage
with gas turbines, may be needed
to preserve service reliability.
Decarbonizing California’s grid
will also require modernizing the distribution system to integrate the distributed energy resources that SCE
expects its customers will continue
adopting, including rooftop and community solar, battery storage, and
electric vehicles. Grid modernization
using existing and emerging smart
grid technologies will allow these distributed energy resources to be better
integrated and optimized and so help
improve overall system reliability,
resilience, and safety.
Electrify Transportation
The electrification of 24% of lightduty vehicles, 15% of medium-duty
vehicles, and 6% of heavy-duty vehicles, with the power to supply those
cars and trucks coming from an
increasingly decarbonized grid, will
help reduce GHG emissions from 169
MMT/year to 111 MMT/year, or 32.2%
of the 2030 GHG reduction goal (Figure 1). SCE sees the need for at least
7 million cars and light trucks,
180,000 medium-duty trucks and
vans, and 22,000 heavy-duty trucks
and buses on California’s roads by
2030 to achieve the state’s aggressive
climate and air quality goals and
help phase out internal combustion
vehicles by 2050.
Supporting 7 million electric vehicles will require a huge build-out of
charging infrastructure, including
up to 700,000 public and workplace
charging stations. For this reason, the
ongoing charging-infrastructure pilots
run by California utilities, which
account for more than 19,000 charge
points today, will need to step up to
rapidly deploy more infrastructure
and chargers to meet the expected
proliferation of light-duty electric vehicles.
The electrification of mediumduty and heavy-duty trucks and
industrial vehicles and equipment,
including forklifts, transport refrigeration units, passenger buses, and
intermodal freight trucks, is underway. Accelerating this will require
developing the adequate charging
infrastructure and innovative collaborations, for instance, electrification of port operations and goods
Industrial
17.2%
Transportation
32.2%
Electric Power
31.1%
Residential
and
Commercial
6.7%
Cap and
Trade
6.7%
Agricultural
6.1%
Figure 1. GHG reductions across six sectors that are necessary to reach California’s 2030 goals. (Source: Southern California Edison 2017a.)
62
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
movement and indoor agriculture.
Larger plug-in electric and plug-in
hybrid trucks are going through the
development stage, and the initial
deployments must be supported by
more charging infrastructure to
deliver clean and reliable electric fuel.
Electrify Buildings
SCE estimates that electrifying nearly
33% of space and water heating in
homes and businesses, in addition to
increased energy efficiency and
strong building codes and standards,
could reduce GHG emissions from 49
MMT/year to 37 MMT/year, or 6.7% of
the 2030 goal (Figure 1). Collaboration
among manufacturers, repair service
providers, and policy makers will be
required to achieve the electrification
of residential and commercial buildings. Current building codes and
standards are based on the 20th century paradigm of electric power generation dominated by petroleum,
natural gas, and coal. A rapid paradigm shift is necessary, based on
SCE’s vision of the decarbonized
grid supporting and incentivizing
the use of clean-electric appliances
and evolving technologies in new
buildings. For example, controllable
electric space and water heating,
powered by rooftop solar generation
with surplus solar power for electric
vehicle charging, could be incorporated in a future version of the zero-netenergy framework, which is focused
on reducing the carbon footprint for
new home construction.
Concurring Visions
SCE’s vision for a clean energy future
is shared by other utilities and government agencies. In 2018, National
Grid, Waltham, M a s s a ch u s e t t s ,
released the Northeast 80 × 50 pathway, its blueprint for reducing GHG
emissions to 80% below 1990 levels by
2050. National Grid’s pathway calls
for 67% carbon-free electricity, 10 million electric vehicles on northeast
roads by 2030, doubling the rate at
which buildings are retrofitted with
energy efficiency projects, and transitioning almost 5 million homes and
buildings that still use heating oil to
either gas or electricity. Similarly,
Portland General Electric published a
white paper in 2018 laying out its
vision for the role of a clean energy
future in achieving Oregon’s environmental goals. The company’s vision
includes achieving 70% carbon-free
generation by 2040, modernizing the
electric grid, and customer adoption
of new technologies, including electric vehicles. In 2018, the California
Energy Commission put forward its
decarbonization strategy for a clean
high-renewable future. The strategy
encompasses a 74% decarbonization
of electricity, 6 million zero-emission
vehicles, and electric heat pumps for
50% of new HVAC and water heating
by 2030.
An Electrifying Future
SCE has developed a blueprint for
integrated electrification that others
can follow for broad decarbonization.
It leverages existing policies and
uses existing technologies to produce the most feasible and costeffective solution to decarbonize the
electric power sector and, afterward,
transition fossil-fuel-dependent sectors to clean electric power.
We can transition to a low-carbon
economy by midcentury, and we can
meet predefined goals to reduce GHG
emissions across all energy sectors:
electricity, fuels, and gases. Additionally, we are proud, as an investorowned utility, to lead the way. Why
SCE? Because many resources and
stakeholders are needed to address
climate change, and electric utilities
have the size, scope, and infrastructure to support efficient electrification
fueled by clean electricity for all consumers. However, everyone is a stakeholder in this effort, and we need a
sense of urgency. Now is the time to
come together and figure out how to
respond to this crucial moment in the
history of our industry and of society
in general. To quote the British thinker
and philosopher Jonathon Porritt,
“The future will either be green or not
at all.”
The possibilities for electrification
are exciting. Not only can it make a
better world, it simply makes business sense. Efficient electrification
catalyzed by clean energy helps meet
customer demands and supports the
creation of more green jobs across
the economy. It creates a new energy
paradigm that can mitigate the
impact of greenhouse gases and
improve air quality and human
health today and for generations
to come.
For Further Reading
Southern California Edison, “The clean
power and electrification pathway,”
Southern California Edison, Rosemead,
CA, White Paper, 2017a. [Online]. Available: https://newsroom.edison.com/
internal_redirect/cms.ipressroom.com.
s3.amazonaws.com/166/files/20187/
g17-pathway-to-2030-white-paper.pdf
Southern California Edison, “The
clean power and electrification pathway: Appendices,” Southern California
Edison, Rosemead, CA, White Paper,
2017b. [Online]. Available: https://www
.edison.com/content/dam/eix/
documents/our-perspective/g17p a t h w ay - t o - 2 0 3 0 - w h i t e - p a p e rappendices.pdf
Biographies
Manuel Avendaño (manuel.avendano
@sce.com) is with Southern California Edison.
Devin Rauss (devin.rauss@sce
.com) is with Southern California
Edison.
IEEE Elec trific ation Magazine / J UNE 2 0 1 9
63
VIEWPOINT
Southern California Edison’s Blueprint
for Integrated Electrification
By Manuel Avendaño and Devin Rauss
ALIFORNIA HAS BEEN
aggressively confronting
climate change for more
than a decade. State policy makers,
supported by two-thirds of the
state’s adult residents (according to
a recent Public Policy Institute of
California poll), have backed increasingly more stringent regulations to
reduce greenhouse gas (GHG) emissions. In 2006, the state legislature
set initial goals to reduce the state’s
GHG emissions to 1990 levels by
2020 and to 40% and 80% below the
same baseline by 2030 and 2050,
respectively.
The key pillars of California’s climate change strategy to meet the
2030 GHG emissions target include
x reducing the petroleum used in
vehicles by 50%
x doubling the energy efficiency
savings at existing buildings
x managing natural and working
lands so they can store carbon
x reducing the release of short-lived
climate pollutants (for example,
methane and black carbon).
More recently, the state has established a target of 100% carbon-free
energy by 2045. The measure also
requires California’s electric companies to procure 50% of their energy
from renewable sources by 2026 and
60% by 2030.
C
Digital Object Identifier 10.1109/MELE.2019.2906633
Date of publication: 11 June 2019
64
I E E E E l e c t r i f i cati o n M agaz ine / J UN E 2019
Given that electric power ac counts for only 19% of California’s
GHG emissions, the state is also
addressing the remaining 81% of
emissions: transportation (45%), agriculture (8%), residential and commercial (11%), and industrial (17%).
Achieving California’s goals requires
significant resources, many stakeholders, and a massive and highly
organized effort. The electrification
of energy end uses—transport, heating and cooling, industry processes,
and others—will be vital to achieve
carbon emission targets.
Southern California Edison (SCE)
and its parent company, Edison
International, Rosemead, California,
have embraced the state’s ambitious
goals. In fact, Edison International
signed on to the “We Are Still In”
campaign, affirming continued commitment to support the Paris Climate Change agreement’s goals,
and has taken concrete steps to
expand the role of efficient electrification fueled by clean energy.
In late 2017, we released a white
paper laying out our vision for the
role of a clean energy future in
achieving California’s environmental
goals, based on the results of an
extensive modeling study to assist
in long-range planning. The underlying assumptions are being used in
current and upcoming planning and
continually updated and evaluated
by SCE.
Evaluation of Decarbonization
Scenarios by SCE
The SCE study focuses on reducing
emissions economy-wide by 180 million metric tons (MMT), from 440 MMT
in 2015 to 260 MMT in 2030. The modeling framework incorporates
economic adoption and renewablegeneration optimization models and
provides a view across multiple sectors of the economy. The study assumes
that 144 MMT of GHG abatement will
come from existing and expected
policies identified in the Scoping
Plan issued by California’s clean-air
agency, the California Air Resources
Board, to address Assembly Bill 32.
SCE used four key criteria to assess
potential measures and technologies
aimed at decreasing the remaining
36 MMT needed to reach the 180
MMT goal:
1) GHG abatement potential (total
technical potential instead of
feasible potential)
2) marginal abatement costs (cost of
an additional unit of abatement)
3) feasibility (for instance, availability of technology, infrastructure
requirements, economies of
scale, consumer preference, and
timing of deployment)
4) likelihood that technology will
enable California to meet its
more stringent 2050 GHG emissions reduction goal (for example,
(continued on page 61)
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