USE OF THE PRINCETON SCOREKEEPING METHOD TO …

1 @TheconsumptionchangespredictedbyPRISM forthesenbillingagreedwiththenOE2changes withinO@ @ FNonefoundMorethan075timesgasvalveampera ge,correctedAirflowrestrictionsincoldair return-removedWasdirty,cleanedWasdirty,r eplacedLeaksinductsandplenumtapedCategor y2 Cycledonlimit, F,loweredto170 ,correctedColdairreturnpulledinoutsideai r,repairedFanbroken,repairedwheretoTBopt ,canthenbeusedtocomputethenormalizedannu alconsumption(NAC),definedasfollows:NAC= Aopt*365+Bopt*HDD(TBopt)*365 NACisthenormalizedannualconsumptioninccf /yearAoptisthebaseloadforoptimumTBinccf/ dayBoptistheincreaseinconsumptionperincr easeinheatingdegree-daysinccf/F-dayHDD(T Bopt)isthenormalizedheatingdegree-dayspe rdaytobasetemperatureTBopt*TheNACreprese ntsthegasconsumptionwhichwouldhaveoccurr edduringthehypotheticalunormal"weatherye ar,andiscomputedforboththepre-retrofitan dpost-retrofitperiodsforeachresidence0 Wethendefinetheratioofpost-retrofitNAC(p ostNAC)topre-retrofitNAC(preNAC)asthecon sumptionindexThedifferencebetweenCIanden ergysaved~IfCIistoorcanbedemonstrated~is thefractionofthan,noenergy,preNAC,NAC, ,andthusthegasNAC,shouldbereducedforthat period~(Comparisonofyearlytotalsofelectr icusagecouldhavebeenusedalternatively).

2 PRISMRESULTSFORRETROFITST hemeanPRISM resultsfortheretrofits(withcorresponding standarderrorsinparentheses)areshowninTa bles2,3,and40 ThevalueofR2outputbythePRISM programisameasureoftheexplanablevariatio ninconsumptioneThusitisindicativeofthere liabilityoftheassociatedNACGA minimumR2of0@ @ @02)1510@ @ FeForretrofitsafter1982-83,35cases,theme anCIandchangeinTBare00950and1e6 F,respectively~Thereareonlyfivecasesretr ofitafterthe1983-84heatingseason, @6 @ @TheaveragecustomerusagedatafromthePubli cServiceCompanyareausefulstandardwithwhi chtocomparetheretrofitsonayear-by-yearba siseAveragecustomerdatafortheperiodwasdi videdintoMay-to-Mayyearstoincludeentires easonS0 Theseventhdayofeachmonthwastakenasthemet erreadingdate,accordingtoPSCoinformation &ThesedatawererunusingPRISM,andCIandchan geinTBweredeterminedfromtheoutputsforeac hpairofpre-andpost-retrofityears~Thesere sultsappearinTable6alongwithpertinentret rofitresults@ @lBenergysimulationprogram(6)

3 6 Theassumedprototypethermalcharacteristic sweresimilartothoseofmanyhousesretrofit, basedonconstructioncharacteristicsdescri bedbyConsumerCooperative~Theresidenceuse dwasaone-story,single-familyhousewith105 0sfoffloorarea~wasevenlydistributedonthe fourwallsandwasequivalentto10%offloorare s@AshadingcoefficientofO@7wasusedtoaccou ntforaverageindoorandoutdoorshadingcondi tions@Typicalframewallconstructionwasuse d,withnowall,attic,orfloorinsulation@Anc rawlspacewasspecified@Thebuildingwasassu medtohavethreeoccupantsandthefollowingap pliances:gashotwaterheater,washer,dryer, range,refrigerator,andtelevision~Thether mostatsetpointwastakentobe68 F$Gasfurnaceheatingwithnomechanicalcooli ngwasThefollowingparametricswererunforth isbuildingusingDOE2:1)Basecase2)Thermost atsetpointraisedZOFtolO F3)Thermostatsetpointlowered2 Fto66 F4)SolaravailabilityQsdecreasedby10%5)So laravailabilityQsdecreasedby20%6)Alterna tefurnaceefficiencycurveFl.

4 Z= + )AlternatefurnaceefficiencycurveF2 ~DOE2monthlyconsumptionresultswereusedas inputstothePRISM program,alongwithDenverTMYdata0 ThePRISM resultsareshowninTable7~Columnnumbersref ertotheparametricslistedabove*R2valuesfo rallparametricsare00997orhigher)indicati ngthatover99% $Forallparametrics,thestandarderrorsonBa ndNACweresmallpercentagesofthoseoutputse ThevaluesofAhadmuchlargerassociatedstand arderrors*Theseresultsareinkeepingwithth efindingsofthePrincetongroup(2)0 The2oneithersideofthethermostatsetpointa pproximatelyequalchangesinthebalancetemp eraturesof+1@7 @998@ @ @9934 TheNACvaluesdeterminedbyPRISM areconsistently97@ @001foreverycaseexamined~REFERENCES1)Car lisle,N~,DeKieffer,Ro,ll*TheColorad0 ResidentialFurnaceTune-ups:AnExamination oftheProgramandApplications,1111 Draft253/7-5-4,July15,1985$2)Fels,M~F~,S ocolow,R~HI$'Rachlin,J~N~)Stram,D00e,"PR ISM:AConservationScorekeepingMethodAppli edtoElectricallyHeatedHouses,9$PU/CEESR eportNoo196,October198403)Dunsworth,T08@ ,Hewett,M0J0'll~DataQualityConsideration sinUsingthePRISMP rogram,nProceedingsofthesecondChicagocon ferenceonenergyconservationprogramevalua tion,Vo101:170-1, 1985$124)Fels,M0F@,1l1lThePrincetonScInt roduction,UPU/CEESAn5)Hirst,E~,Goeltz,R0 'White,Do,"UsingEnergyBillingDatatoDeter mineHouseholdEnergyUseFingerprints)uProc eedingsofthefirstChicagoconferenceonener gyconservationprogramevaluation,Vol~1:27 5-295,August,1984~6)DoeUsersManual,Contr olDataCorporation,1983