rexuS: ofthewater-energy thechallenges Meeting treatment andwastewater theroleofreuse withenergyrequired forwater areintertwined, O Waterandenergy production, soreusing forenergy andwaterrequired treatmeni, r s o n e to address water and e andclosinq wastewater and pttrnconHel Lunnovl,xwlte-xocHoo reducingresources.vnlrHrtHn is ofwastewater furtherthereusepotential explainhowexploring keytofutureurbanliving. rTrhe Sun is the source ofall I energy on Earth, and watet is the basis ofall life on out planet. The relationship between these vital rnedia only becomes clear on closer inspection: energy ftom solar radiation fuels the natural 'rr?ter cycle. Gigantic quantities ofseawater are desalinated by evaporation and transported as clouds, returning to eaith as fieshwater plecipitation.Without the input ofenergy from the sud, the entire water cycle would quickly come to a standstill. \Vhen warer expertstalk about the nexusofwater and energythey do not usuallyinclude thesenaturalglobal without which lile on Earth processes, would not be possible.ltis becauseof this common onrissionrhar,witlin the lastdecade,the terms'waterfootpdnt' and'virtual water'havearousednore and more interest.Florveveqin general, usedfbr the cechnicalprocesses energyconverslonrequrrewaler, while water usercquiresenergy.Even at rhislevel,thenexusofwater and energyisinexrricable,and the link belween the t\,vois stronger tl, an nright appearat {irst sight. Directly and indirectly,water is essentialfor checonvelsionofenergy. Water is used!o generateelectricily by hydropoweqwaveor tidal polver. Huge quantitiesofwater areneeded!o dxploreand extractfossilfuelsand for power plants,which usestean to drive turbinesand cooling weter to dissipate heat.In addition,the cultivarionof encrgycropsfbr biogasand biofuel producrion alsor.equires water. There is alsonanifold trseof energyin the rvatercycle:enelgy is requiredfor lvater and rvastewater distlibution, usageand treatment, with householdsrequiring rhe largestshare.On the other hand water and wastewatercontain energy in severalforms,which can be used in generatingelectricityand heat. To sum up: energyis neededfor lvater cyclenTar,agemer,!, water is neededfor energyproduction and water reusecan help to seveboth.As with water reuse,theunlocking and enhancedreuseofthe elcrgy con tainedin waslewateris a key tool in solvingthe waler energynexusthat urbanisedcentresfaceworldwide. nexus Thewater-enetgy Solving the rvatet energynexus to preserveour envlronnent ls undoubcedlythe challer,ge ofthis cennrry Populationgrowth and increasingliving standrrdsheve depletedresourcesand caused 10000000 I 000000 100000 biodiversitylosses, and evenclinate change.Itis thereforevital to rcvise our nodels of development,especially in terms ofholistic managemenc of water and energy, The traditionallinearapproachto wa[er managementoflen doesnot recogniseor undersrar,d, asit should, the inceractionsberweenwater and er,ergy.Wirhincreasingwater scarcity and soaringenergycosts,thestrong links betrveenwater and energy arebecoming ilcreasingly obvious. The effectsofglobal warming and climacechangereinfolce the need for a holistic approachto managir,g energyand rvater- alolg with rTutri ents in an inregratedsystemthat fits rvith gr,owingurban development- for life Energy The rotal solarpower supplyto the earthis in the rangeof10 nrillion -Watts per person[V/cap),most of rvhich is driving rhe globa1natural freshw:rtercycle (Kroissand Svardal, 2011). However,sol:rrirradiation and freshwater availabilityare extremelyvariableover tine and region,and population gro*th is often not adequatelymatchedby water or energyavailabiliry As illustraredin Figurc 1 the current nreanglobal primary power consumption is about 3000W/cap, and up to 6000W/cap for developedcountries. Some 1000W/cap ofenergy consurnptionis usedfor transportatiol and aln-rost 200W/cap for food produc tion. By comparison,the watel suPply uses10 to 50W/cap,while highly effrciencbiologicalnutrient removal wastewatertrcatmentplantsneeda powerinput ofbetweer, 0 and 20 'W/cap. Pumping energyrcquirenents for water systenr and energyrequirementsfor wastewaterpolishingbefore recyclingstronglyvary dependingon the specificlocal situation,butarein tl, e sanreorder ofmagnitude. Energy forwater t0000 '|000 o E 100 Food wsbr Global$lar Glob.l |naan6lob.l ftean Trafc pdmary prim.rY tampo.t prodlclion 3upply lreatnent iftadidon po*r pows The energyrequiredcoconveyand levelsis in the trcat water to acceptable rangeof0.05 to 5 kVh/m', depending on the water source(fieshwacer, tigure 1:Global 0nmary!ower seawatero[ wastewater)and specific regionalparameterssuchasclimate, consumption water availabiliry r,vateruse and andpowertor watersupply .populationdensity.Thetypical andI/astewater speci{icenergyconsumptionofthe (adapted major elenenls of!he urban water treatment phltlinAehkdo& cA @ z.etururt, o"""tinrtion lEraot e Z.ffWml stt" wati,,Projec! Cornel, 2010;Voutchog2010). 'Water end wastewaterEeatment facilitiei energyconsumpcionvaries acrossa similarrangefiom 0.2 to 1.41.5 kWh/mr dependingon the pumping head,leveloftreatment and plant capacity.Waterconveyancecan reach r,aluesof 1. 1 kWh/m' and may have a signifrcandy higher energy footprint in specificcases,such aslong-distance transportation: for instance,the StateWater Project in California, for example,uses2.5 kWh/nr. Adranced pastenater treatment for nutrient removal'and water reuse requires more enelgy. Nevertheless, water reuseis one ofthe most cost and energy eflicient alqernativewater resourcescomparedto desalination and long distalce water transpertation. Energy efhcient advancedwater recycling plants such asthe Groundwater Replenishment System (GWRS) project in OrangeCouncy, California, are producing rerycled rater ofdrinking water quality with a relatively low energy footpiint of0.53 kWh/rnr (Mehul, 2010). Comparing this to one ofthe most energyefficient desalinationplants,Ashkelonin Israel, which hasan energy consumption of 2.9 kWh/mr (Voutchkov,2010) and a sinrilar treatrnent capacity (265,000 m3ld and 330,000m3ld,respectively), lhe energy footprint ofadvanced water reuseis 5.5 times lower. Energy optimised nutrient removal with anaerobic digestion, asfouird for example at the Strasswastewater treaffnentplant inAustria (220,000 peopleequivalent(PE)),notonly hasa relatively low energy footprint of0.35 kWh/rn- but alsoproduceselectriciry, achieving energy self+ulliciency Q..lovaket aI.,2011). Until recendy,seawaterdesalination wds limited to regions with a predomi nandy desertclimate.Thelatest technologicaladvancesand en in water producassociated decrcase tion costsand energy demand have exp:nded the tecbaology's use to coastalareasffaditionally supplied with ftesh water resources.Desalination's energy consumptlon is still higher than ocher water supply alternatives, but the implementationofhigh efticiency reverseosmosis(RO) rnembranesand energy recovery deviceshas enabled the specilic energy consumptionto be reducedto2.5-2.8 kWh/m3 at large desalination plants, and cut annualisedspecfic costs. Globally, Iainwater haryesting @WH) technologies are becoming increasingly popular a.sthe desire for buildings to become rnore adaptable . and resilient to climate change and population growth increases.It is (' 035kwh/rr, St""" eneqysolf€uffichtltIIIWIP,luofia I O.Sf*Umftt[89-SE&q!9!4, "t €4 i fl: E 3z g $r tlb. otr[Ifio frbl lvrtu Pnll|trin.ryld.ldirq /r.dvdd 6'dvdld lrubtgrt dl.fihton ttqb|nt ftlht! tludg. drd!6$t nuficdoi 2r ing equipment and schenes charac. Figure Typicalenergyterisedby high energyconsumption, footpridof tpically in the rangeof0.3-1.2 themajor elenenls kWh,/mr with a signiiicant carbon andprocesses in footpdnt.It shouldhoweverbe noted watercycle that the majodty ofrainwater harvestmanagenenl iflg s]stems arc at small scale,being (ldattedfromiicda used for individual or high-rise buildandComel,2010,ings, so a direct cornparison with large Wilson,2009,facilities is not appropriate.Innorztive Voutcikov, 2010 gravity-driven RWH slstems,rccoverandlazarova ing kinetic energy from the water flow etat,2012).or using solar energy,rnay help reduce energyconsumptionand improve the sustainabiJiryof rainwater harvesting. Waterforenergy The water footprint ofenergy (that is, the volume offreshwater used in energy production) is not well documencedand understood.Nevertheless, in the framework ofsustainable development, the water footprint of conventional :nd renewable energy sourcesis becomingone ofthe major criteria ficr assessingtheir sustainabili+ W'ateris a crucial component in producing power and renewable energy (such asgeothermal power, heatpumps,osmoticpower andbioethanol) .Wich the growing interest in renewable bioenergy its high water demandpresentsanother challenge,particularly in conditions ofwater scarciqr ' As shown in Figure 3, the water footprint offossil fueJsis relatively low, in the order of0.38 to 0.72rn!/MWh energy for gas,nuclear and coal (Gleick,1994).Thewater usedby power plants for driving turbines arrd cooJing is sirnilar, around 1 to 3 m3lMVh. Nwertheless, the significance ofthis water requirement was highlighted during the Eurcpean 'huadred-year summer'in 2003,when numerous power plants were forced to reduce their output or even shut down becausethere was insufficient cooling water available. BR W|!rRe|||. Bnck:h $.irbr Rftr d-.lin.do. &dln.ton R:tnrel hrrvltf|rg al energy sources,at up to 250 mrlMwh, equivalent to 6 8m'/GJ (Mekinnen and Hoekstm,2011).The shift towards bioenergy requires more water,up to 600 and 1130m3lMWh for biogas and biodiesel from crops respectively(Gerberu-Leenes et al., 2009).Dependingon the methodsand rypes ofsubstrate used,the water demandis between68 and 443 nrlMWh for biogasproduction, between 144 and 1440rn-lMWh for bio-ethanolproduction,and betr,veen 360 and 2160 nflMWh forbiodiesel production.Evenin regionswith a comparatively large rainfall, irrigation water might be needed to cultil'ate energy croPs. An imporant factor for water consumptionin energyproduction is the quality and a ilabiJity ofused water Someprocesses poilote water more than others, and in different ways.For example, cooling lowers mosdy changethe temperatureofche wate! whereasthe water usedfor coal exEactionor plant opention (ash hardling or flue-gas desulphurisation processmake-up water) might be contaminated with suspendedsolids, acidsor heavymetals.ln termsof ar,ailability,er,aporation should be assessed.ln addition,water for cullivat ing crops is no longer directly available once used,in contrast to water fiom one-pxs cooling slstems. The rnost water efiicient way to generatebioenergy is to use total biomass,including the parts without an economic \,2lDe,to gene$te heat. Genenting electricityis the second bestoption. In principle,genenting energy from already availableresidues, for instance ftom the food industry, should have priority over the production of energycrops,because the wster demand is not the only maj or factor - further iniuences on the ecos)stem can be considercd, such asdeforestationJo gain further nexus Solving thewater-enelgy Integratedresourcemanagementin the Cities ofthe Future or eco-cities representsa major pandigm shift in the way new cities will be built or older ones retrofitted.The aim is to achieve a changeftom the current unsustainable statusto sustainability,neet the net zero greenhouse emission targes, ald reuseand recycle water and recovet resources,including nutrients (Novomy et al.,2010).A closedurban v/ater-energy cycle can be achieved thrcugh a holistic approach of\tater management'combined with heat and energy recovery Decentralisedor semi-centralised water distdbu4on systemswill be more efiicient for future cities when water reuseis inevitably considered @ieker et al.,2010).Watersuppliescanbe tailored to match demand more closely in centralisedwater inftasffuctures, adapting water quality to the given use. With substituting fresh water with appropiiately treated recycled water, it is possibleto save30 50% ofdomestic water demand.The implementatron of the semi-centralised approach to urban infrastructures would not only a1low substantialwater and energy saving,but would also provide new opportunities for energy recovery from biowaste throughout biogasprcdsction and for the'useofnutdents in sewagedudge to produce biosolids for agriculture and otheruses. It is importan! to sEessthat alternative water resourcesare not in compebition with each odrer or with conventional water supply sources. -They should insteadbe consideied as essentialcomponentsof an inlegrated water menagement Portfolio that bdancestheir usedependingon local conditions to improve weter and energy management and efticienry and securea reliable and sustainablelongterm weter suPply.The sYnergies benveen desalination and water reuse have to be strengthened asthere should be an incentive to keep.desalinated watel in the water useloop aslong component ofa sustarnablewater resourcesmanagement plan, does nbt provide dre gamevalue chain irnpact in terms ofreclaiming the energy already embodied in the water product. For alternative water resources, choosing the best option for water management meansdeveloping and applying a multi-criteria analysis, or the triple bonom line approach, basedon economic, environnental and socialimpacts. r0 000 4W Ito 5rs E e I lwo- ryo!.. 8l9dl6.d G.s ud€r Corl _sohr-Cnr|e coF ctopr aspossible,minimising freshwatei to the sea.lnthe Cities of discharges the Futurc, all weter resources,including rainwater and seawategifavailable, should be comidered in solving the water-energy nexusSustainability in water rcsource planningrequiresconsiderationof the embodied energy in the water cycle, and in water recycling in particular (Wilson,2009;Meda and Cornel, 2010).Waterreuseenablesenergyuse within the water cycle to be optimised, particularlywithin decentralisedand semi-autonomousurban slstems,and at a treafinent level that adheresto the 'fit for purpose'principle.Recycled water needsto be delivered at a cost that isjustifiedby its purpose,so energy-intensive processesshould be limited unlessexceptionally high water quality is requircd. It is impoitant to sfiessthat the value ofrecycled water includes the embodied energy that is reclaimed from the water rycle.when the capitd and operational costsof embodled energy in recycled water are accounted for, dre overwhelming savingsfrom operational energy recovery substantially ofiiet the costsofwater reuseinfrastructure flJifilson, 2009).Reclaiming treated westewaterpromotes eni/ironmental benelits by emuring better water quality and optimising energy use within the water cycle.Water consen€tion, while an important Toward energy-positive wastewatet tteatmeni Wastewater treatment plants have the potential to become environmental pladorms, and to provide an energy source for tomorrow's eco-cities as part ofa systemcharacterised by the srnallestpossible ecological footprint (GWRC,2011). It is important to stressthat energy self-sufficiency for wastewaterfteatment faciliEescannotbe considered asan objectivein itself,but asa component ofa globalwater management shategy that takesinto considera[on regional and local specilics aswell as environmental,social, and econornic issues,Imprcung wastewetertreaunent performance is and should be the ' prirnary objective, followed by choosing the best availablepractices and technologies for enhanced energy efticienry and the bestuseofsludge for energy produchon and rccovery. To be more attrachre, innovative techaologies for energy recovery must be cost-effecdve, reliable, easyto operate and should have no adverseimpacts on water quality or the envrronment. An analysisofcurrent practices shows that energy self-sufticiency tigure4: for wastewatertreatment is a feasible Lefi:Strass goal. However, for existing plants IYWIP intustia this requires a long optimisation (Cr€dit Bernhardprocess,relatively high levels of y{eti) investnent ald the use ofinnovative Right: AsSarnra technologies in new; more energyWMBlordan efticient facilities (GsrF.C, 201 1; (CrsditDegemonl) Svardaland Kroiss,2011). Figure3:lvaie] foolprintofenergy prodrclioI (Adapted lrom Gleik,lgg4, terbens-Leenes ct al,2009and iieconnenand [oskslra,2011). , I Rawsewage R o b L r s tb c n c h m a r k i n g p r o s r a r r r r e s lrl)d glridcliucs lor cncrlr' oprirnis.rtiolr h l ' c b c c r i n r p l c n r c n t c dn r E L r r o p c s i n c e t h c 'e r r l v 1 9 9 ( h ( A u s r i i r . F r r n c c , Gernranl. SrvirzerhrLl :rrd SrvcLlcu), d e n r c n s n - e t i r gI c o n s i d e r r b l cp o t c n t i : r l f - o l c n e r g , vo p t i n r i s a r i o ni n e x l s t i r r g pl:rnts ofbetr.een 20 anct 50% ( L i n d t n e f e t x ] . . 2 0 0 8 ; W e ! te t r l . . 2 0 0 7 ) . S i n r i l i u e r e r s , vr e d L r c t i o n p r - o g r a n r r e sh i l r , eb e e r l r u l c h c d i n A u s t r r l i : r .t h e U S u d C a r : r d u ( W E l l F 2 0 l { ) ) . A s I l e s u l r .r c v c l e l \ r a s r c w i r r c r trc.!rellr phllts i]l Europc hlvc achieve.l thc- soirls ofhigh crcrgv cllicier)c\ arld cncruv scl1]snt'licicncl.. Tod.nl t\\.o lnuniciprl uasrervrter t r c r t r n . - n tp l a n $ i n A u s t r i a r r e e l l c r q v seli sLrfflclerrr the 220.00(l l'jE Str':rss p l a D t ,( F l g r r t e{ t : r )r n d t h e 5 ( 1 . ( l 0 0 l ' ] E \Xrolfgrngsc'c'lschl phnt (Wctt ct.rl.. 2 ( ) 0 7 :N o \ r k e t a l , 2 1 ) l 1 ) . r n c lt h e r e r r e irurllbcr ofothcr ongoing prcjecrs. Iioth ofdrcAustli:rn energl seli s L r f l L c i e npt1 : r n t sh l v e a c t i v l r e d s l u d e c p r - o i : e s ew s i d r r r r r r i e r t r f i r ) o \ ' : r l( $ , i t h 1 c s r h l r l r r q t o t r l p h o \ p h o r u s / 1 ,r n . 1 ovcr.(j0% nitroecr rcrlxrval) and .ncrgv oPtimis;rtion ovcr a period of l o L r r r d 2 0 , v c : r r s . T h ck c , vc n e r ' g 1 optinli\.rior nrL'r\Lrfesfor rhese t t ' o p h n t s i n c l u d e o p t i l r r a lr e r r t i o u c o n t . o l . h i s h e r r e c o v e r vo f p : l r r i c u l r t c cuborr f;our thc pr irn;rr,vsertlellsto p r o v i d c n o r c o r g . u r i cr r a t t e l f o r . r n : r e r o b i cd i s e s t i o n .o p r i n r l s e c l n r e r o p h i l i c i r r i r c r o b j cs l r r d g cd i g c s t c l s , e ] l e r s r e f f l c i e r r rc o r r b i n c d h c l t r d p o \ \ , e r( a l H P ) L r n i $ . r n d u s t ' o f r h c I ) F M C ) N p r o c c s sl o r c l c r m m o n i f l c a !lor ofthc sl dgc .lc\\'.rtcring filtr-etc (Novrk ct i]..20i 1). \ r . , . 1 . . J . i., . 4 . , . , . . . r i ^ i,.. " - , . ^ , . r - , 1 ir thc litcraturc on the desielr arrd ,:,pcrrtron of ncw energy-sullicient wr\tcwxtcr trcxtnlerlt planrs.'f he As S . u n r ' .pr h n t i n J o r d r n ( F i g u r e - l ) 1 sI vcr\' sood e:ianrple. achie!'irle r trrgct of over 90% oIre]llsufncicucv ill e n e r g J s i r r c ej t s c o l r n l l i s s i o r i l l e i n 2 { ) { ) i i( F i c v c z ,2 t ) 0 9 ) . T h i sn e n ' 2 . 2 million 1'[ capaciw hciliq'trcrts 2a)7.0(l(lnr'/d ot $'aste\,irrcr lbr the inhrbitantsofAnrnl:r md thc s u r l o u r d j n e l r r - ] s ,p r o d u c r n g . r q L r . r l i t v cll]llcut ibr rcusc in igricultulc. Thc plant has an rctir.:ted sludge procL\s Nith ritrcqcn rcnovrl and d i s r n l c c t i o r ru s i n g c h l o r i n e . o d o u r t r - c , r t r r c nat | d a n a e r - o b i d c i e e s r i o no f t h c n r i x e d s i u d e e . l ' h e e r e r : l t v. l e r r n r r d f o r . h i \ p l a n t ( 8 5 % t o 9 5 % ) i s r r r c tb y n e x t s e l r e r i t i o l l r e c h n o l o g i c ss L r c hx ! h v d r a L L l i ct u r b i l e s r l c l b i o g r s - d l i v e n c o g e t r e f a r i o D . T h er l r c e l rc l r c rl j v c o r r s L 0 r r p t i o pr lc r p o P U l : r t i o 1e1g r i v a I e r ) ti s 2 1 . 3 l i w h / p c | 1 , , , v(rt h e p o p u l r t i o r r c c p i v a l e n t r e l a r e dt o 1 1 0 g ( l ( ) l ) , / P E . d u , i r h ; rn r e a n Figure 5:Energy 96 kwh/cap.yr (68 k\4hlcap.yr) C00halance sciematic for influeni typical wastewater treatmenl Ilants 168 kwh/cap.yr (adapted from (146kwh/cap.yr) Corneletal,20ll 72 kwh/cap.yr andLazarova etal, (78 kwh/cap.yr) 2012],. Effluentand respiredCOD StlrssWWTPIsenergyconsLlrrptiol. \ )ich is 19.9kWh/PE.verr(Novrk ct :r1,2{)11).but theAs Sflrrn pliru .rlsoh:rsdisinlecrion:rrclodour trc;rtmcDt l:]cilitles. Encrqt' rccovclv fiorr servagellorvs in thcAs S.urlra pliDt :linrsto recovcr thc potcntial(kiretic)errergycrrrbod icd irr rvastervarer Hor',,evcr, tltc cncrq'v IWA WorldCongress onWater, Climate andEnergy Biogas Electriciiy 43 kwh/cap.yr (38 kwh/cap.yf) 15 kwh/cap.yr (12 kwh/capyr) 53 kWh/cap.yr (30kwh/cap.yr) Digestedsludge 28 kWh/cap.yr (26 kWh/cap.yr) Lossesand water neat ,vickl ofthis energ"- sourrc is rcl.rrivelv l i n i t c d a r d d e p e n d so r r l o c . r lc o n d i tion\, piuljclrhrlv clcvrtion ditlirercc arrrl llo$,s Cherrric:rll,,-bound erer15' lionr the oreilrric lllxrter in \\'astc$,rtcr l u s t h c h i q h e s tp o r e r r t i r l l b r r c c o v c l v ( M c d . r . r n dC o r r c l , 2 { ) 1 0 ) . H c r c . t h c e n e | g v b r l r l ) c c d c - p c n , : losn t h c o r a r r r i c c o n c c r t r r | r o r ) o f t L r cw : ] \ t c \ \ n t e r .o r r f]Mt \-t WorldCongress onWater, Climate andEnergy "i*:trJ#i:L" The naugurallWAWorldCongresson Water,Climateand Enefgywlll be heldfrorn 13 to 18 tu]ayif Dublin, lreand.Over1000delegates, profess onalsin thesethreekey interlinked areas,willmeetto d sc!ssthe stateof-the-ariand debatekey ssues. RayEarle, ihe congress chair,explains thatthlsls a groundbreak ngevent:'Thlsis theveryfirst t me that we havebroughtthesethreelmportantissuestogether.We havehada lot of singleand some biatefaeventsonthewater-enefgynexus,bltthisistheflrsltimeweareookingatwater,energyand c]|mate change.' Awholesetofdlsclpneshaveto cometogether, he notes,rangingfrom reseaTchersto busnesses, thinktanks,deveopers,agricutura concerns, constructors, reta ers,andtheservice sectoramongothers. 'Thsisthefrsttirnewehaveookedattheseissuesinahos|cway,'lvl.Earleadds.Heseesthe needforjoinedupthlnkingonthesethreevitalafeas, tocreatepolicyandadvocacy, which soneof lWAskeyroes. 'Thereal driverls literalysLrrv va ,' he notes.'Thef nanca al'rdenvironmental cr sesgo hand n hand. The UN saysthattheworldwilldoubleiis population by2050,withthe pressures ihatwillbr ngiorwater andsanltat on,andat thesametimecl matechangewilibe bfingjngnaturaidtsasters.' Heobserves thattheseissuesarefundamentalenergysLttmateyfrornthesunandwaterfrom rarn.'lt is aboutgettingbackin harmony withnature,howdo wegetmoreefficient, cleanerand more goingforwardandwe haveto do it now' sustainable Thlsis themainthemeof theconference, heexpains,warnngthatthecurreftpathbe ng 'Weare us ng resources takenls unsustainable. that we are borrowlng, that we shouldhavetell forfuturegenerations.' To reversethe currert leves of oveTconsumptionwe haveto ookat howto harnesssoar energy, hydroelectricity andw nd powern a clean,efficient andsustainabie way,headds,acrossrneefr re processof generatiof,stofageand transmsslon,and usingth s greenenergyto rnovewaterarourd and provlde the powerrequired for saf tation. l\,4r Eare warns:'Wewon'tsLrrviveunlessweookaitherequirementsofthefood chaI andecosystems anda the requirements forwaterandenergy. lfwedon'tgetjoinedupthnkingalloftheprotocoswill reman dysfunctiona, lherew ll be moremortaliiy,we will losethe foodchainwe dependon and therewill be morenaturaldsasters.We havegoiio get backto softengineerng and naturasolutons-' 'lt hasto happennow Thisevent,he explains, ts invaluable. lt s absoutelyacrisissituaton-economically, envronmenta lyandin planstrateg termsof sustarna bility.'lt wi be mportantto ca yfor climatechange,he noies,andto accountfor ts consequences, property forlfstance,the poteniial andenvironmental impacts of floodng. Headdsthatbothadaptation afidm tigation Ieed to beaddressed, noting:'Wewafi a verystrongdec arationlrornlhe congress,sothat the IWAcan playa strongadvocacyrolefor futurecongresses and dec s on-makers.'Bylis Sledmafl f i c c o u n o , v i ss p c c i f L cp e r c . r p i t as ' . r t c l . o l r s u n r P r i o l l ,t h e t , v p co f s c N c rs .t l r c pelccntrge rrd rlpc ofindusn ul c l l l L r c r t si r n d o t h c r l o c r l c o r r r l l t l o r r s . F i g u r e i i l l L r s t f : r t ct \ \ o c \ r r p l c c r r egr r b r h n c , : s( C o rr r c lc t r l . . 2 ( l l i r L u z i r o v . ro t 1 1 . . 2 0 l l ) . I n b o r h c . t r c st h c t r c i r t ] r r e nP a r ' ( ) c c \ s ci su c t h c \ i n ] c . i r r c l r r r l i l r gp l r r n : r r , rs' c t t l i r g . n i t I i t i c l t i o n r r l c r i u i f l c r t i o n . . r n : r c r o l r i cd r r r l g c s t x b i l i s i r ! l o nr n . l u s c o i b i o g r s . T h c r l r r i l r r s s u r n p t i ( ) l si r c t h c ( l O i ) l o . l | ] s o f - l l i r r d - 1 2k g r c . r p . r ' : r, r c t h r n c ploductiou o10.35 I (ll Ir/qalOl.) r n r l . r r L c t l r r D ee r e r i l p o t . r ) t i i r l o j l 0 k W h , / r r ) ' . 1 ) e s p i t ci h c s l i g h t h r r o r c corccrrurterl rl;rstorrter irr thc ilst i n s t i r c c . t h c e n e r s v L r . r L ; r r ricsec l u i t e s i r n i h r : 5 7 / " ( c ) 6 k W h/ c r p . r ' c r r ) t s t r . r n s i i r r c t lt o t h c ' c l i g * t , : r . u r d o r r l v 2 6 f ' ( 1 3 k w h / c x p . \ ' t i s t r ; u r s i il c d i n t o m c t h . u t e .U s i n g d r e s r n t c . rlr corvelsion cillcicrcv of 32%,o 3.9% ofthc crrbodrcd chenric,rl c r r c r g v i s r ! ' c o \ ' c r c dr s c l c c t r i c i l v L r o u r r r el n e r g y i r w . x t c l . r t c r i s r t i l l . r r , r e l o b i cd i g c s t i o r t .E r r L r g i r g rnclgv cllLcicrt rr,.1 erelgr p r o r l L r c i rg t e c h r o l o g i e s .s u c h r s r r ) i . r o b l l L r e lc e l l s .n r i c r o b i r l c l c c t ,o l l s i sc e l l s . u r dn i c l o b i r l r t c \ r l i n r t i o n c c l 1 s . : r r fcr p c c t c d t o b c t i . r s i b l ei n t h c n c . r ' t i r t r u c . M r r i r r i s i n g $ c c r c l g , r ' g . r n rh , o n r c . r c ho i t h , , ' p o t e r t i . r l v r u r c c s o f c n c l g l s l r r q s r r r l g e n . r . r t i o n ( s c cb o x ) t o L r 1 l ] r l l o i r w l s t e ' t , r r e l n - c . r t n r c r rptl . r n t s , p r r t i c L r J r r l vd r e l ; r l g c s to n f \ . r o r - f . o l c r r I r L lf v | l ) n r . l l l v t o g e r r e r r r er l l o f d r c c n c r g r r r c c c l e tl o r p l , r r t o p e m r i o n . r n d c r c r r r i c l l . r r c r r c r q ) s L r p h L si r f i n r e s . Whilc in its inlincr'.rt prcscnt. susrrirrblc n rrtc't'rter r'e:rrnrent . r n d r c L r s ch : l c c o r r c o i r g e a n d . r r cl i l c l v t o q . r i r g r c . r t c ri n r p o l t r n c e i n t h c p l r ) r ) i l ] 1 l o l _ i l l ( c g r ' r r c r$l r t c l anrl cncr'{vrrn:rrgcnrcrt s_vstcrrr i n t h c f i r t L u r . A s* i t h l r t c r r c r r s c . t h c ' L u r l o c k i n g. u l l c r r l t r c c c l r c u s c oflhe elrcfgv contxinfd in t'.rstct':rtcr is.r Lcv tool ir soh'irll the nercr' e n e r g v c \ u s r L r . l tu $ i ] l ) a e r r a l . e s ice tolldrvirlc. 10-200k RENEWABLE ENERGIES 5-10% FROM ENERGIES SEWAGEFLOWS 2 - 10o/o SLUDGES 40 -+ 60-80% ENERGYSAVINGS (finebubbleconlrolled ae.ation, (wind power,photovollaic.sola. ihermal power, geoihefmal energyefficienimotorsand numns) (hydro'iurbines, healPumPs, in sewerheatexchangers) (anaerobic sludgedigestion, pfe-tGatment to increase d;gestability) remarks Figure 6:Major Concluding 'I h e c u r l c r r t c o n f l q L r r . r t i o ror f u r b a n components olthe 'positive enefgY \ . r t c r l l r i r r i r i l l r n e n r \ \ ' \ t c m \ r c . ] r ) st h r t plant'-zones s i g n i f r c . r t q r r r r l r i e ro l \ \ ' l t c r x l r d where theenergy r n r r ! ' \ : l r c c o r l s u r r r c dr u L l n u n i . ' n t su l e efficiency ol i n c * r . i c r l . l v r l : r r i r q . d . H i s r o f i i j i l l \ : waSlewaler r r r t c r ' . r n r lc r c r g r h l r l c b c c l l n r l n l g e r l treatment can i r c l e p e n r l t n d y rb u t i r t h c C l i n o f t h e heimproved.F L r t L r rreh e n h o l c l a t c r c y c l c s h o r r J d b c n r . r n . r g c ci rl : r s u r t . r i r : r b l c* : r v t h r t l i n r r t r r : r e r g l c o n s L r n r p t i o n: L n d r r r . l \ r n ) r s c c\ r r c f g v 1 e . o \ ' e f\ ' . ( 1 5k W h / c r p . ) ' t . A firn,:Lr c trl corrrporelrtol pronrising tcchrolos Thcrrrost s L r r t r i n a b l e$ r t c l r n . r r r . r l 1 c r r l dl ri e r sirl t b r r e c o v c rr r r g t h t ' c h e n r i c . r l hp r o p t l L r l b l n d c s i g r r . T h i sc o r s i s L so f d j s ! ri b L r t c d\ \ ' . r t c rs L r p p l i c \s\ h e r c . clLrdurg r r r u l t i p l cr r r t . r - r - e r o u l c c si n I r i r \ v r t c r h r r v e s r i n s .u l e c o l l c t t r d : r c r o \ st h c ' u r b r l r r r e i r o n r i n i n i s c p aniwillrequire p L u p i n g l c q u i L c r r r c r r t sr r. r l r v h c r - c ' treatment a g obalanaysisof lhewastewater 0pt misingtheenergyof a g venwastewater o n h . r f i r c t i o n o i t h c r \ r t c r s 1 l 1 p l vi s andthe bestintegrat on of theenergy waterqualityrequirements trainin termsof thecLrrreft treatment s t h r e e f o d r tm o p f o v e e n e r g y e f f c e n c y , t o r n a x i m s e t h e u s e o f s l u d g e l o r e n e f g y t r c . r t c t lt o p o r i r b i cs t r n c l : r r c l s . At ht c c r r t l ssues.Theam o i t i r c c h . r i r , s . r r t e N r t L ' r|-r c : r l r l l ] J r l t Fo!r ma n components ior designand producton,andto recover sources. energyfrom nternalor exlernal i r c l L r d c sr L c c c r r n r l i s e d ; r n dc c L r t r . r l i s c d h iat vL er sbeese)n o p e r a t i o n o f a ' p o s t v e e n e r g y (ptahnatt i s , a p a n t t h a t p r o d u c e s m o r e e n e r g y t h a n c o n r p o r ) ]rJ) t \ t o o p t i r r r i s ! c' r c f s \ ' et a , 2012): dentf ed (F gure6, Lazarova r'.'rolelr .urcltutcr l cr.rse,V/.i\ tc$,rlciand bestpracllces tor owenergyconsumplon (upto Energy savngsfroin mp ementngtechnologles h . r st o b c c o r r s i , . l c r cnr lo t o l r l v : r \ x 20% energyrecovery): . Useof bestavallabe energyrnanagernent practces,suchas optimsaton of aeratioasyslerndesign, f o t c n u r l l l t r n ) . l t i v c \ , J t c r r e s o ! u - c cf o r \ , l f l o u s \ \ n t c r f e u \ . : p l r r F o s c s , L n rl tl \ o efflcent aeraton control,and useof premum eff c encyrnotorsand variabe frequencydrivesfor arge org.trric J s J s o r u a eo t n L r r f i e r ) t s . u r d aerators) purnpsandaeraton devces(suchas b owersand mechanical . nnovatrve c o r \ r l f t r L r s .\ h r . h : 1 1 cp o t c r l t l , rL ol theconcentrated wastestreamhandlngtechnooges,Suchass deskeamtreatment \ourac\ oi elrefg\: on to reducetheenergyusedin biologica d geston bydeammonificat returnflowfromanaeroblc Thc potclrirl opdons fir solvrrg treatment wastewater . Nextgeneraton treatmenttechnologies t l r c \ y . r t c r c r l c l l i \ ' 1 r e \ u sc . u ) D . i r L \ o wastewater lreatrneni for domestc wastewater or decentrallsed c o n s i r l c r c dl r o n r r h e p o i n t o f v i c t o i and reusesyslems r h c e o n c c p t o 1 : d r cu r b l n n r c t . r b o h s n r , s t i c h c ' q u r r r cas c i n t o r l i l i r g w r t e n r . Energyrecoveryfroms udge(up to 60-80%energyrecovery)l primarysettingeificiency n i r h r s i n r i l . r t i n g: u l 1 c \ c r c t i r ) g l i r u c . Bestpractcesto mprovedigester designandoperationr enhanced . lnrovatvetech,roogiesfor sludgepre treatment t r ( ) r ) sA. s r r i r l i l i l r ! ! l ) o d ) ' .i r i s c s s c r r t i r l beforeanaerob c d g€stiof;co d geston (cogeneratiolr, . Combifedheatand powergeneration gasase ectricity to h.lt rcoclirg loops in ortlcl to fuelcels, frorndigester rrr\inrisc thc eDer$ obriinfd ti1)rn mlcroturbines) or mechanca enefgy(directdrlveor st rlingengnes),gasf cation . Directreuseof b ogasafterpuf I cationt0 the gasgf d t h c i n p L r t \( f i ) o ( 1c. u e f i l r ' ,\ ' r t c I r n d . llse of b osords I agrlc!tureor asa so dfue r L r ni e n t r ) b c t i r l c t h e r o r i c re s i c l u c ' s ( p o 1 1 u t : L n.tusr d c r r c r g i n g c o n t r n r i .,rntr) r'e erclc tccl. 1Vlor c'o!er'. Energyrecoveryfromsewagef ows therrna, hydrauic, potentlal(up lo 10%energyrecovery)l . Useof specf c ocalcondtions(topography,ocationand infraslrllcture) c l o r r l r ] cl o o p h r | r ' i c l s v i t c r t s c . u t to recovereneagylrom the tirr bcttcl sourcc bc irrtrorlLrced p ant'sinf uentand/ or etfluent r rrnt igoe . I n n o v a t v e w a s t e s t r e a m e n e r g y h a r v e s l i n g t e c h n o l o g e s s u c h a s h y d r o t ! r b i n e s a f d h e a t e xscchp a r .r. s r s l e 1 1r r t i x b c . r t l c c o v c rv r n d b i o g l s p r o r l u e t i o u . Thc Sur ls thc rollce oirllcrtcrgr, sources suchassolat,w nd or geolhermaenergy(upto energyfromextefnal ProdLrction of renewable o n E . u t h . r n r l u r t e r - i r t h c L r . r s iosf r L L 10%efergyrecovery), . l l s e o f a l t e r n a t i v e r e n e w a b l e e n e r g y t e c h n o l o g i e s t h a t a r e f e a s b e f o r t h e s t e s p e c f c c l r n a t el i t i o n o r r r p l r r c t l t i r o u r c o n r r r i n l t u t , . r sn . r t c l p r o f i ' s i o r r l t . r ' e s e r l c h e l s wh ch requre re ativelyowin t a capiiacostsandsitelootprnt, andfinanca ncentlves, conditions perod rrLl Llecision m.rl,crs. to s.rti'gurr-drhe and havea shoirreturnon nveslment . lfnovative ruirr rlrivels oflifc on orrr pllrct microw nd turb nesandcombned ta c{herfilaSystems, suchas pholovo technologies treatment energy fromwastewater Gaining Reterences BickerS,ConteLP anrlWaget M Qat0), SuituraLized suppb,dntltrcdtnentsfst.,B: ituelnkd hlfrnstrrcrrcolutia'ts JarJast!rctur\ 6 | (1 1), ututu drcrs.Water S.ien@ETuhnoLosy, 2905-2913. Comel4MedaA d BiekcrS (2411), trie ts.ltd Wdltcujdtet rs a \oM( of utryl, otiWatetSdenee. Etiitt t: lcnji.evdkr.Tieatisc Pt Wildercr,Else etverkg FieNczE (2009),As Sdrra WI,VTP: t vadt dter torLjaftl!the e erfy s+s"frd trcatunltpldnt.IWA ConJerereon l,l/atdn d Enug,, Capcfidlcn,Dcntna&,29 ta 31 OdaL)er 2409. Cdrrus betl\W HaeklttaAY anl t an dt MeetTH (2009),Thc idterJoatprht t'I aJthe NdtioiaLA.ddeny hiaencrg,. P/j.eediitss 9f S.ienreof the U"i@t1Stnte\afA,rctid ( P N A S ) . 1 4 5e 5 ) . Ckitk PH (1994),Watetd d.n.t&,.Annudt Reietu Enug, Etu,irornent.19. CII/RC (2011),WdtuA eneryyin the rbanwatu q,.le:i'|ryftt'ingenev qtheiery ij1nniipal vasteuatut@tne t. Repon preparcdby rhe NanydttgEttrnonncnt Ewat'lt RtsedfthI nitune (NEWRI), PUB Sinra]].re and Clnbdlwatcr RcsedrchCo.tlition (G\4/RC) , Snryaporc. KroissH andSnrdal K (2011), EneW dnd ltasterntethearnox.11lt IWA Confuenrcon Delign,Operdti.nard Eoqol ns of Laryc WdtteutdterTicatnvntPkt^, Scpt.nbu I ta 9, About theauthors 2A| 1, Buddpelt,Htlluary. Lazarova L a . d r c M V C h a oK H a d C o E I P ( 2 0 1 2 ) , Valentina isSenior Project Waterenewinten.tioti!in pdterrcule.IWA ManageratSuezPublishinr,lanion, U K. H, ond KroksH QA08), Environnemenl. Lhdtuet S, SclLddr But chna rbits of larscnn nic| dl uask water l(warg-Ho Choo trcdtmeltplntltsneatingorer 140,400 PE il isanAssociate A ltia.Water Seicrc ETi&nolog,,57(10) Professorat 1187-1493. l(yungpook MeddAdnd Canel P (2010),EneW dtitl llational t|dtct:ftLatianship! ad ffiouerypotential.IWA University,l(orea.WdtLrard Eftryy onJcrc"tt,A detddtx,'fhc Peter Cornelis a Professorat Iechnische lJniversitat Ilarmstadt, Germany. Ncthe dnds,l0 to 12 Narcnber2010. Nau',tkO, Keil S an.l Finkn C Q01t), Exdnryh: of atrl, selJ-sqnek' tluuti.ipal nuttientrenoutlplants.Water SeicceE 'ltdlnoLory, 54(1) 1-6 . NorohiyV (20 10),Wot'!t energ nexft n)wdftls zeropoLlution a CHC uissions oJ .futuffc(e.o)dtics.WatetttltdltnrcturcJw stahabtuConnuniics (HnoX, No]|dt/] V a Nd!o, tr c.l,, IWA lruqintin*, Lrldoil, pp15 58. Sr.t.ldl K aM tuoissH (201 1), E ergl |cElit" n1xJor ua!|e )aterteatxux.ILtte| S.ie'ift e'fl.hmlag, 64(5) 13 5 f | 3 5 I. VorxhkovN (2014),Stauaterdesdlitldtioti: turcnt tre isa chaLLengts. DLsdhnion - d Filtrdtian+ Se4tatiarPubliatio'l,5(2).4 7. WERF (201A),O,e hu' oJstokekeryy rcd dio trogrms andr delircs.fatthe u)dltcu)iterlelor. Cdntwell ct dl,WERF Report Ofi/S O 6 R07b,Wdtct Eht i n n tlentdl Research Fofidatiot a|d IWA Pbblilhntf,120pp. WettB, BulMucr Kalid FiuuL C 0047), EnetlaysctJtfficienq, asaftasibL..an.LptJor ua\tewnt.r hedh etu synons.Pto.&dinfs IWA LeddingEtlgeTeehtblor:tColfere ee,Si rapare, Se|itetbet2047,!p21 to 21. REGISTER NOW IWAWorldCongress on Water,Climateand Energy ReEister Nowto SecureDiscountedFees -sponsor or Exhibitat the Congress pleasevisitwww.iwa-wcedublin.org Formoreinformation. from acrossthe globeto exchangeideas, The Congresswill attract over 1000 like'mindedwater,climateand ener€lyprofessionals linkednatural,utilityand explorethe stateof the art and debatethe keyissuesunderlyingthe scienceand practiceofthese inextricably infrastructuralissuesof our time. It will featurea largeindustrypresenceand trade exhibition. ContactCongresssecretariatat: 2012, c/o KeynotePCo IWA-WCE Suite26, AngleseaHouse,CarysfortAvenue, Blackrock,Co Dublin,lreland tel: +353 1400 3660 Fax:+353 1400 3692 Email:[email protected] T rI :-.i9 Rr?HSl:v tFaS rlr ireIondinspires.comO.v".€gln === ESHltr' upo ."!N[ffi'"'s'