Energy Storage + Renewables

AhmedMUHAMMEDa.muhammed@necsaudi.com

+971-55-287-7803NECSaudiArabia

•  Today’sgridsrequiremoreflexibilitytoaddress:–  Increasedrenewablegenera?on

•  Compensa?ngforvariableenergyresources

–  ChangingloadpaDerns•  Genera?onnowdistributedtoloadcenters(PV)•  EVchargersshiJingconsump?onpaDerns

–  Agingtransmissionanddistribu?onnetwork•  Infrastructureisagingandneedsreinforcement

•  Upgradesinurbanenvironmentscanbedifficult

•  Energystorageinthegridisapowerfultool–  Increasecapacityu?liza?onforgenera?on,

transmission,anddistribu?oninfrastructure

Addingflexibility,efficiency,andreliability

Preparing Grids For A Renewable Future

Renewable Capacity Firming GridStorageApplica?ons

•  Problem–  “Firm”genera?oncapacityisconstantpowerproduc?onwhichisguaranteed;there

canbepenal?esifthepowerisnot“firm”andsystemoperatorsmustplantocompensatefornon-firmcapacity.

–  Renewablegenera?onlikewindpowerandphotovoltaic(PV)solarpowerhaveintermiDentoutputduetotheresourcestheyrelyon.

Constantpoweroutputisdesired

Renewable Capacity Firming

Solarpanelarrayscanbeshadowedbycloudcoverwhichaffectstheirabilitytomaintainconstantelectricityoutput.

Windspeedcanchangeoverthecourseoftheday,insomecasesblowingstrongerintheeveningcomparedtoaJernoon.Thesewindspeedvaria?onsleadtointermiDentandinconsistent,non-constantelectricityproduc?on.

–  IntermiDentrenewablegenera?onisduetovariabilityintherenewable“fuel”–inthiscase,sunlightblockedbypassingclouds.

Constantpoweroutputisdesired

Renewable Capacity Firming

Gridsystemoperatorsdesirecommitmentforconstantpoweroutputtominimizetheneedforotherresourcesintheirsystem,forinstanceacombined-cyclegasturbineoracoalplant,torampupanddown,whichcanincreasetheiremissionsandopera?ngcosts.Withenoughnon-firmandintermiDentgenera?onlikewindandsolar,greaterinvestmentinflexiblerampingresourcesisrequired.Insomecases,morecoalplants,gasturbines,orpeakerplantsneedtobeinstalledtocomplementtherenewablegenera?on–theveryfossilfuelresourcesthey’remeanttodisplace!

•  ValueAddedbyEnergyStorage–  Energystoragecanperformrenewablecapacityfirmingbystoringenergyfrompeaks

orfromotherbaseloadresourcesandusingittofillvalleysinrenewablegenera?onoutput

–  AllowsintermiDentelectricsupplyresourcesuchaswindorsolartobeafirm,constantpowersource–avoidingpenaltyfeesandcrea?ngasteadycontractrevenuestream.

–  Mayreducepower-relatedcharges(forexamplecapacitypaymentsordemandcharges),oritmayoffsettheneedforequipmentsuchaspeakerplants.

Constantpoweroutputisdesired

Renewable Capacity Firming

Source:SANDIAReportSAND2010-0815,EnergyStoragefortheElectricityGrid:BenefitsandMarketPoten:alAssessmentGuide,JimEyer&GarthCorey(February2010)

•  ValueAddedbyEnergyStorage–  Howdoesenergystorageworkwithnon-firmrenewablecapacity?

Constantpoweroutputisdesired

Renewable Capacity Firming

+ =EnergyStorage FirmRenewableCapacity

PVisintermiDent–passingcloudscausepoweroutputtodropquickly.Whentheclouddeparts,electricitybeginsflowingagain.

Energystoragecanfillinthevalleywithpreviouslystoredelectricity.

Thenetresult?Firmrenewablecapacity–consistentpoweroutputfromaPVarrayevenwhencloudspassby!

Power

Time

Power

Time

Power

Time

IntermiMentPV

PVsolarfarm

Curtailment Avoidance GridStorageApplica?ons

•  Problem–  Renewableenergyissome?mesturnedoffor“curtailed”tonotexceedtransmission

anddistribu?oncapacitylimitsorbalancethegenera?onwiththeload.Thiscurtailedenergyislostandnotsold.

Transmissionlineshavealimitedtransportcapacity

Renewable Curtailment Avoidance

Source:hDp://www.eia.gov/todayinenergy/detail.cfm?id=16831

Example:InTexas,windwasfrequentlycurtailedduetoexcessproduc?onthatcouldn’tbeabsorbedbyexis?ngtransmissionlines,causingnotonlywindfarmstoshutdown,butalsonega?vepowerpricesasenergyimbalancesdrovereal-?mewholesaleelectricitypricesdownduetotheoversupply.Asaddi?onaltransmissionwasbuiltovertheyears,curtailmentsdroppedandnega?vepricinglargelydisappeared.Buttransmissionisexpensivetobuild–insomecasesenergystoragemightbeabeDerop?on!

•  TypicalSitua?ons–  Renewablegeneratorswillsimplyshutdown

andnotreceivepaymentforelectricitythatwouldhavebeengenerated,evenifthewindisstrongorthesunisbright.Sincetheycan’tsellittoloadthatdoesn’tneedit,orusetransmissionthatcan’tmoveit,therenewableelectricityis“spilled”orwasted.

•  Issues–  Electricitythatwouldhavebeengenerated

andsoldbutisn’twillnega?velyimpactthegenerator’stotalreturnoninvestment,decreaseitscapacityfactor,andingeneralreducetheeffec?venessofthegenerator.

Transmissionlineshavealimitedtransportcapacity

Renewable Curtailment Avoidance

•  ValueAddedbyEnergyStorage–  Usingenergystoragetocapturewindenergyundercurtailmentcondi?onsgivesthe

systemoperatormoreflexibilitytomanageoversupplyorconstrainedtransmissioncapacityandavoidnega?vepowerprices.

–  Avoidingcurtailmentcanalsoincreasetheamountofenergygeneratedbyrenewables,andincreasetheamountitcansell

–  Addi?onally,ifrenewablegenera?onoccursata?meofnega?vepricing,storagecouldactuallygetpaidtochargeup!

Transmissionlineshavealimitedtransportcapacity

Renewable Curtailment Avoidance

Renewable Time-Shifting GridStorageApplica?ons

•  Problem–  Renewablegenera?onlikewindandsolaronlygenerateelectricitywhenthewind

blowsorthesunshines.Many?mesthisdoesnotcoincidewiththehighestpricethatitcanbesoldatorwhenitisneededmost.

Sellrenewableelectricityatpeak?meforahigherprice

Renewable Time-Shifting

Thisisaproblemwithwindwhichtypicallyblowsstrongeratnightwhendemandandpricesarelow,butPVgenera?oncannotmeeteveningdemandandcanalsobeexposedtolowerdemandpricingontheweekendsorholidays.

•  TypicalSitua?on–  Electricitysoldatcontractedfixedpricewhenitisproduced–  Electricitysoldwhenitcanatreal-?mewholesaleelectricityprices,

regardlessofwhatthatpriceis

•  Issues–  Renewableelectricitycannotbeprovidedwheneveritisneeded–

forinstanceineveningsaJerthesungoesdownbutdemandisincreasing

–  Sellingrenewableelectricityatthemarketpricemaynotenablethegeneratortorealizethemaximumvaluefromtheelectricityifsoldathigherprices

Sellrenewableelectricityatpeak?meforahigherprice

Renewable Time-Shifting

Did you know? Time-Shifting of energy can be accomplished for any generator, not just renewable generators. Any power plant that finds itself in a position where it could benefit from selling electricity during peak demand is a candidate for time-shifting. Renewable generators suffer the most since their “fuel” (wind and sun) are entirely uncontrollable, unlike coal, gas, nuclear, or hydro power.

•  ValueAddedbyEnergyStorage–  Renewableenergy?me-shiJcanallowop?mizedrevenuewithenergystorage

chargingduringoff-peak?mes,anddischargingandsellingthestoredelectricityduringon-peak?mes.

Sellrenewableelectricityatpeak?meforahigherprice

Renewable Time-Shifting

Anexampleisshownhereforawindwithenergystorageonasummerday.Windgenera?onisstrongeratnight,whenenergy’svalueislow,andisusedtochargestorage.Abouthalfoftheenergyusedon-peakisfromwindgenera?onthatactuallygetsgeneratedoff-peak.Theresultisfirm,constantpowerforfivehours,beingsoldatahigherprice(on-peak?me)ascomparedtoalowerprice(off-peak?me).

Source:SANDIAReportSAND2010-0815,EnergyStoragefortheElectricityGrid:BenefitsandMarketPoten:alAssessmentGuide,JimEyer&GarthCorey(February2010)

A word on arbitrage A commonly used term for time-shifting is “arbitrage”. However, the strict definition of “arbitrage” is the simultaneous purchase and sale of identical commodities across two or more markets to benefit from a difference in pricing. Time-shifting is not the same since the “buy low sell high” mechanism occurs at two different times separated by several hours, and are not simultaneous.

Renewable Ramp Management

GridStorageApplica?ons

•  Renewablegenera?onoutputisvariableandcanchangerapidly.

•  Thispowerrampcanmakeitdifficultforsystemoperatorstobalancethegrid.

•  Tocompensateforthis,someu?li?escanimposerampratelimita?onsforvariableenergyresources

Controlrapidchangesingeneratoroutput

Renewable Ramp Management

PVsolarhasbeenfacedwiththeserampraterequirements–notably,theUSislandterritoryofPuertoRicoimposedwhatitcalledMTR(minimumtechnicalrequirements)onanysolarpanelprojects,requiringrampratelimits.SimilarrequirementsareineffectforFrenchislandslikeGuadeloupeorReunion.

Windgenera?ononislandslikeHawaiitypicallyhaverampratelimita?ons,keepingpoweroutputchangestounderacertainMWperminute.Thisisdoneinanefforttopromoteamorestablegridenvironmentandonethatsystemoperatorscanmoreeasilymanage.

Renewable Ramp Management

NECES’s11MW/4.3MWhGSS®installa?oninMaui,Hawaii

▐  Wind Ramp Management ▐  11 MW Power Capability ▐  4.3 MWh Energy Capacity ▐  9 Battery Containers ▐  3 Inverter Containers ▐  External Chillers, Transformers ▐  Operational December 2012

Renewable Ramp Management

GSS®HRwithupto2MWoutputpercontainer

NEC ES provides multiple energy storage technology options on its GSS® platform designed for high power, balanced power and energy, and high energy

•  Renewablegenera?oncanlimitup-rampsonitsown,buttypicallycannotlimitdown-ramps.

•  Energystoragecanslowdownthedown-rampstomeetthelimita?onsimposedbythesystemoperator.

Howhasitbeenworking?

Renewable Ramp Management

Renewableresourcewithenergystorage(GSS®)

Thank you!

PleasevisitNECEnergyStorageSolu?onsformoreinforma?on:hDps://www.neces.com/solu?ons/for-the-grid/AhmedMUHAMMEDSolu?onsArchitectNECSaudiArabiaa.muhammed@necsaudi.com