CH2M HILL 2485 Natomas Park Drive Suite 600 Sacramento, CA 95833 Tel 916.286.0224 Fax 916.614.3424 DOCKET April2,2012 11-AFC- 2 427930.DI.DR DATE APR 02 2012 RECD. A R 2012 MikeMonasmith P 02 SeniorProjectManager SystemsAssessment&FacilitySitingDivision CaliforniaEnergyCommission 1516NinthStreet,MS15 Sacramento,CA95814 Subject: SupplementalDataResponse,Set2 HiddenHillsSolarElectricGeneratingSystem(11AFC2) DearMr.Monasmith: OnbehalfofHiddenHillsSolarI,LLC;andHiddenHillsSolarII,LLC,pleasefindattachedelectronic copiesofSupplementalDataResponse,Set2,whichprimarilyaddressestheproject’sBoiler OptimizationthatwasdiscussedduringStatusConference2,onFebruary28,2012. Inaddition,wehaveattachedthematerialsthatarebeingsentunderseparatecovertotheGreat BasinUnifiedAirPollutionControlDistrict. Weplantofilethisinformationelectronicallyandfollowupwithhardcopies.Pleasecallmeifyou haveanyquestions. Sincerely, CH2MHILL JohnL.Carrier,J.D. ProgramManager Encl. c: POSList Projectfile Supplemental Data Response Set 2 (Boiler Optimization) Hidden Hills Solar Electric Generating System (11-AFC-2) Application for Certifi cation Hidden Hills Solar I, LLC; and Hidden Hills Solar II, LLC April 2012 With Technical Assistance from IS061411043744SAC Hidden Hills Solar Electric Generating System (HHSEGS) (11-AFC-2) Supplemental Data Response, Set 2 (Project Description and Visual Resources) Submitted to the California Energy Commission Submitted by Hidden Hills Solar I, LLC; and Hidden Hills Solar II, LLC April 2, 2012 With Assistance from 2485 Natomas Park Drive Suite 600 Sacramento, CA 95833 Contents Section Page Introduction............................................................................................................................1 ProjectDescription(PD1)........................................................................................................2 ReductionintheNumberofBoilersandChangedPowerBlockArrangement.........................2 RelocationofSwitchyardandGasMeteringStation.................................................................3 InstallationofaTemporaryConstructionWell..........................................................................4 Summary....................................................................................................................................4 VisualResources(VR1throughVR5)......................................................................................9 AttachmentA–Figures AttachmentB–Tables APRIL 2, 2012 ii CONTENTS Introduction Attachedaresupplementalresponses(Set2)byHiddenHillsSolarI,LLC,andHiddenHillsSolarII, LLC(collectively,“Applicant”)totheCaliforniaEnergyCommission(CEC)Staff’sdatarequestsforthe HiddenHillsSolarElectricGeneratingSystem(HHSEGS)project(11AFC2).Thesematerialsarein responsetoquestionsraisedattheFebruary22,2012workshop,informationrequestedbystaff, anddiscussionsattheFebruary28thStatusConference. Thesupplementalresponsesaregroupedbyindividualdisciplineortopicarea.AFCfiguresortables thathavebeenrevisedhave“R1”followingtheoriginalnumber,indicatingrevision1.Additional tables,figures,ordocumentssubmittedinresponsetothissupplementaldataresponse(supporting data,standalonedocumentssuchasplans,foldinggraphics,etc.)arefoundattheendofthisData ResponseSet. APRIL 2, 2012 1 INTRODUCTION Project Description BACKGROUND On February 27, 2012, the Applicant submitted a letter to the Siting Committee for the HHSEGS project, made up of Commissioners Karen Douglas and Carla Peterman, informing them of a proposed design change for the HHSEGS that would reduce project environmental impacts, enhance plant efficiencies, and make the design more consistent with that of the Ivanpah Solar Electric Generating System (07-AFC-05C). These “Boiler Optimization” changes were discussed at the Status Conference. DATA REQUEST PD-1 During a status conference held by the California Energy Commission on February 28, 2012, the Siting Committee for the HHSEGS project requested that they be kept informed about the Boiler Optimization. Response:Followingacoordinateddesignreviewintendedtoidentifyopportunitiesforreduced environmentalimpactsandenhancedplantefficiencies,HiddenHillsSolarI,LLC;andHidden HillsSolarII,LLC(theApplicant),isproposingtomodifytheproposedHHSEGSprojectto optimizecostsanduseofnaturalresources.Primarily,theApplicantisproposingtoremove thelargeauxiliaryboilersfromthedesignforHHSEGSaspartofa“BoilerOptimization” effort.BoilerOptimizationwillresultinairemissionreductionsforHHSEGScomparedto thoseidentifiedintheApplicationforCertification(AFC). Reduction in the Number of Boilers and Changed Power Block Arrangement Undertheoptimizedprojectdesign,thenumberofboilersateachpowerblockwillbe reducedfromfivetotwo—thelargeauxiliaryboilershavebeeneliminatedandthemedium sizedandsmallestboilerswillremain.Theoperationoftheremainingboilershasalsobeen reoptimizedtosupporttheoperationofthesolarreceiversteamgenerator(SRSG)ina moreefficientandeffectivemanner. Asintheoriginaldesign,thesolarfieldandpowergenerationequipmentwillstarteach morningaftersunriseandwillshutdownwheninsolationdropsbelowthelevelrequiredto keeptheturbineonline.Eachsolarplantwillincludea249MMBtu/hrnaturalgasfired auxiliaryboiler(thisisthemediumsizedboiler,previouslycalledthe“startupboiler”)that willbeusedtoprewarmtheSRSGtominimizetheamountoftimerequiredforstartup eachmorning,toassistduringshutdowncoolingoperation,andtoaugmentthesolar operationduringtheeveningshoulderperiodassolarenergydiminishes.Asintheoriginal design,asmallnaturalgasfirednighttimepreservationboilerwillberetainedandusedto maintainsystemtemperaturesovernight. Giventheremovalofthelargeboilers,theannualnaturalgasuseintheremainingtwo boilersundertheoptimizeddesignwillbereducedbyabouthalfcomparedwithtotalgas useintheoriginaldesign.BoilerOptimizationwillalsoreduceemissionofgreenhousegas andcriteriapollutantsforHHSEGSunderallscenarios.Asaresultoftheoptimization,the generalarrangementofthepowerblockhasbeenrevised.Figure2.21R1showsthe APRIL 2, 2012 2 PROJECT DESCRIPTION HIDDEN HILLS SEGS SUPPLEMENTAL DATA RESPONSE, SET 2 updatedplotplan.Inaddition,Figures2.22aR2and2.22bR2providerevisedelevation drawings.AllfiguresareprovidedinAttachmentA,Figures. Thechangeinthepowerblockalsoresultsinachangeinequipmentredundancyasit appliestoprojectavailability.Asummaryofequipmentredundancyisshownin Table2.31R1(alltablesareinAttachmentB,Tables). Themajorcomponentsofeachsolarplant’spowerblock,asrevised,aredescribedin Table2.32R1.ThepowerblockisservedbythebalanceofplantsystemsdescribedinAFC Sections2.2.3through2.2.11. Minordesignchangeshavebeenmadetothefollowingsystems. Boiler Feedwater System TheboilerfeedwatersystemtransfersfeedwaterfromthedeaeratortotheSRSG.The systemwillconsistofoneturbinedriven(booster&main)pump,onemotordrivenbackup (booster&main)feedwaterpump,andonemotordrivenstartuppump.Theturbinedriven pumpissizedfor100percentcapacityforsupplyingtheSRSG.Thestartuppumpwillbe sizedfor25percentcapacityandincludeavariablefrequencydrive(VFD).Thebackuppump issizedfor50percentturbineloadandincludesaVFD.Thepumpswillbemultistage, horizontal,andwillincluderegulatingcontrolvalves,minimumflowrecirculationcontrol, andotherassociatedpipingandvalves.SeeTable2.31R1forfeedwaterpumpspares. Separateboilerfeedwaterpumpswillbeprovidedwiththenightpreservationandauxiliary boilers. Condensate System Thecondensatesystemwillprovideaflowpathfromthecondensatecollectiontanktothe deaerator.Thecondensatesystemwillincludetwo50percentcapacitymultistage,vertical, motordrivencondensatepumpswithVFDs.Thesystemalsoincludesdeepbedcondensate polisherswithoffsiteregeneration. Demineralized Water System Thedemineralizedwatersystemwillconsistofionexchanges.Resinmediafromthevessels willberegeneratedoffsitebyathirdpartywatertreatmentsupplier.Spareresinforthe twoplantswillbestoredinthewarehouselocatedinthecommonarea.Demineralized waterwillbestoredinthedemineralizedwatertank. Power Cycle Makeup and Storage Thepowercyclemakeupandstoragesubsystemprovidesdemineralizedwaterstorageand pumpingcapabilitiestosupplyhighpuritywaterforsystemcyclemakeupandchemical cleaningoperations.Majorcomponentsofthesystemarethedemineralizedwaterstorage tank;demineralizedwatertreatmentsystem,andtwo100percentcapacity,horizontal, centrifugal,cyclemakeupwaterpumps. Relocation of Switchyard and Gas Metering Station BasedondiscussionswiththeBureauofLandManagement(BLM)initsreviewoftheValley ElectricAssociation’s(VEA)rightofwayproceeding,Applicanthasagreedtorealignthe naturalgaspipelineandtransmissionlinetoavoidthemesquitethicketsthatwould otherwisebeimpactedbyconstructionofthegaspipeline.Sincethegaspipelineand transmissionlinesharearightofway,bothlinearsareaffectedbyanyroutingchanges. APRIL 2, 2012 3 PROJECT DESCRIPTION HIDDEN HILLS SEGS SUPPLEMENTAL DATA RESPONSE, SET 2 However,theBLMproposedrealignmentresultedintheneedtomodifytheswitchyardand gasmeteringstationlocationstobetteralignwiththenewlinearcorridorroute.Movingthe switchyardandgasmeteringstationnorthwithintheCommonAreawouldhaveresultedin potentialimpactstoculturalsitestheApplicanthascommittedtoavoid.Thus,inorderto implementtheBLMalignmenttoavoidthemesquitethicketandavoidtheculturalsites,the switchyardandmeteringstationarenowproposedtobelocatedimmediatelyacrossthe stateborderonBLMlandinNyeCounty,Nevada. Theserecommendedrevisionswillalsoresultinthegenerationtransmissionlinesonthe HHSEGSsitebeingplacedunderground,whichwillreducethepotentialforvisualimpacts andreducefuturemaintenanceneeds.Sincetheswitchyardandmeteringstationwillbe movedimmediatelyacrosstheborder,anypotentialimpactsofthosefacilitieswillbe