2016 4 27 neea eql wct electric hvac€¦ · resistance hvac, and inverter driven heat pumps april...

Integrated DSM:

Communicating Thermostats and Energy Management for Resistance HVAC, and Inverter Driven Heat Pumps April 25, 2016

Prepared for: Northwest Energy Efficiency Alliance Dave Kresta, Program Manager

Prepared by: EQL Energy, LLC 3701 SE Milwaukie Ave., Suite A Portland, OR 97202 Primary Author(s) Ken Nichols, Principal /EQL Energy / 503.438.8223 / [email protected] Gregg Hardy, Ecos Research Mike Lubliner, Washington State Energy Office www.eqlenergy.com © 2016 EQL Energy, LLC. All Rights Reserved This document was produced by EQL Energy, LLC in accordance with an agreement with (Client). Client’s use of this report is subject to the terms of that agreement.

EQL Energy LLC | Communicating Thermostats with DHP and Electric HVAC

i

1 ProblemStatements......................................................................................................................2

2 Summary...........................................................................................................................................22.1 Findings....................................................................................................................................................22.1.1 ResidentialelectricresistanceHVACusagecontinuestogrowinthePacificNorthwest.22.1.2 DHPshavepenetrated6%ofelectricHVACPNWmarket,andgetting50%ofhomepotentialsavings...............................................................................................................................................................32.1.3 Web-enabledcommunicatingthermostatshavedemonstratedelectricenergyandcapacitysavingsthroughchangesinuserbehavior,improvedsensorandequipmentcontrol,andcustomersatisfaction............................................................................................................................................32.1.4 Web-enabledcommunicatingthermostatsexistforallresidentialHVAC,thoughfewexamplesinresistanceHVACandinverterdrivenheatpumps..................................................................42.1.5 UseofWCTsinresidentialelectricHVACwillprovidetheregionwith226aMWofcosteffectiveenergysavingsandover2,000MWofseasonalcapacity.............................................................5

2.2 Recommendations................................................................................................................................62.2.1 MarketResearchandoperationaldetailsofWCT/HEM.................................................................62.2.2 LabStudies..........................................................................................................................................................62.2.3 SEEMmodeling..................................................................................................................................................72.2.4 FieldStudies........................................................................................................................................................7

3 Background......................................................................................................................................93.1 MarketSizeandEnergy/CapacitySavingsPotential................................................................93.1.1 MarketSize..........................................................................................................................................................93.1.2 EnergyandCapacitySavingsSummary...............................................................................................103.1.3 SavingsbyEquipment,Sector,andRegion.........................................................................................123.1.4 RegionalHVACControlsandDHPMeasuresandResearch........................................................18

3.2 ResidentialElectricHVACproductsandcontrols...................................................................203.2.1 OnlyafewDHPvendorsoperatewithWCTs....................................................................................203.2.2 ThereareahandfulofWCTsthatworkwithelectriczonalandFAF,andthreeaftermarketWCTsthatworkwithbothDHPandresistanceHVAC.......................................................223.2.3 ResistanceHeatingManufacturers........................................................................................................223.2.4 WhatbenefitsotherthansavingelectricitydoWCTsprovidethismarket?.......................233.2.5 Whatlimitationsdoestheproducthavethatatypicalcustomermaynotexpect?..........23

3.3 GapsandmarketbarrierstoadoptionofWCTandHEMwithelectricresistanceHVACandDHP...........................................................................................................................................................243.3.1 Gapsandmarketbarrierstopotentialenergyandcapacityefficiency..................................243.3.2 Communicationprotocolsbeingusedandstandardsperspective..........................................243.3.3 Themesforcontinuedresearch,andfieldstudies..........................................................................25

3.4 NEEAstakeholdersareinterestedinWCTandBuildingEnergyManagement............254 Bibliography.................................................................................................................................26

4 References.....................................................................................................................................28

EQL Energy LLC | Communicating Thermostats with DHP and Electric HVAC Page 2 of 30

1 Problem Statements 1. ThermostatcontrolssoldwithDHPs,zonalheat,forcedairfurnaces,andhearthheatersdonot

reflectcurrentstateofarttechnology,leadingtoreducedenergyandcapacitysavings2. ExistinghomesthatinstallDHPsoftenhavesecondaryheatingsourcesthatareseparately

controlledandreduceoverallenergyandcapacitysavings.

2 Summary CommunicatingThermostats(WCT)arecurrently20%ofthenewresidentialthermostatmarket,andexpectedtoincreaseto50%by2020.RecentresidentialstudiesusingWCTsshowbothelectricenergyandcapacitysavings.Thesesavingsareoccurringthrough:

a. Improvedtechnicalcontrolofequipmentandfaultdetectionanddiagnosis(FDD),b. Learningalgorithmsanduseofsensorinformation,e.g.,weatherandoccupancy,c. Userbehaviorchanges,d. FirststeptofullHomeEnergyManagement(HEM),lighting,waterheater,etc.,e. Automaticresponsetogrideventsorpricing(capacity).

TheprimarymarketnowforWCTsaresinglefamilyhomeswithASHP,CentralAir,andGasFAF.However,thePacificNorthwestresidentialHVACloadremainsover60%inotherHVACtypesthatcouldbenefitfromWCTintegrationandfunctionality,includingElectricResistancezonalandFAF,inverterdrivenMini-splitheatpumps,andsectors,e.g.,Multifamily,ManufacturedHomes,andSmallCommercial.

2.1 Findings

2.1.1 Residential electric resistance HVAC usage continues to grow in the Pacific Northwest

PNWresidentialelectricresistanceHVACmarketisexpectedtogrow1%annually.Inthenext20yearsthenumberofhomeswithnon-heatpumpelectricHVACwillmovefrom1.9MM,consuming1,185aMW/yrto2.9MM,consuming2,260aMW/yr.(Navigant,2015)ThisPNWmarkettrendisreinforcedbyCadetManufacturingwhoexpectstosell200,000units/yrofelectriczonalheat,or


regionalestimatesofmanufacturedhomeswithelectricForcedAirFurnacesbeingsoldat2,200to4,000units/yr.Strategiestoreducethisenergyusageincludeimprovementinbuildingcodes,weatherization,improvedwindows,anduseofvariousheatpumpstoreplaceorsupplementnonheatpumpHVAC.WethinktherearefurthersavingsinthismarketbyintegratingWCTsandenergymanagementsystemswithnewandretrofittedelectricHVAC.

2.1.2 DHPs have penetrated 6% of electric HVAC PNW market, and getting 50% of home potential savings.

DuctlessHeatPumpmarketpenetrationinPNWhasbeenslowerthanexpected;anIllumestudyrecommendsmovingthe85%stockpenetrationforecastedin2028to2034.(Illume,2015)Todate,thePNWhasinstalledover100,000DHPs,orabout6%ofthemarket.MostoftheinstallationsareinsinglefamilyhomesandrepresentsupplementalHVACtoexistingelectricresistanceheating,andmayaddcooling.Energysavingsfromtheseinstallationsareabout24aMW/yr.Givencontinuedgrowthininefficientelectricresistance(ER)HVAC,pursuingWCTsandcontrolsforthisequipmentisagoodhedgeagainstslowerDHPandHPpenetration.

HomesthathaveinstalledsupplementalDHParegetting50%ofpotentialsavingsduetocontinueduseofotherlessefficientHVACsystems,andbehaviorthatincreasesenergyuse.(EcotopeInc.,2014).Non-HPheatcontinuedtoprovide50%ofhomeheating,andDHPmodelingstudies(SEEM)estimateda20%increasedusetoprovideotherbenefits,e.g.,increasedtemperaturesetpointsinmainlivingandsecondaryspaces,reducednon-electricsupplementalfuelconsumption,andincreasedoccupancyduringheatingseason.1InterviewsofDHPusersfoundfewoccupantsusedsetbackcapabilitiesandfoundDHPthermostatsnotuserfriendly.

2.1.3 Web-enabled communicating thermostats have demonstrated electric energy and capacity savings through changes in user behavior, improved sensor and equipment control, and customer satisfaction.

ThroughanEnergyTrustofOregon(ETO)studyofNestWCTthermostatwithAirSourceHeatPumps(ASHP)energysavingsrangedfrom5-20%ofheatingload(averageof786kWh/yr).(ApexAnalytics,2014).Savingswerenotachieveduniformlybyallparticipants,whichsuggeststhatsavingsaredependentonsituationandcustomerbehavior.Apexanalyst,NoahLieb,suggestedthesefindingsweredirectional,notstatisticallysignificant,basedonasamplesizeof161participants.Findingsincluded:

a. Manufacturedhomeshadalmostdoubletheaveragesavings.b. Lowerincomehomeshadalmostdoubleaveragesavings(1,654kWh/yr)c. Priorprogrammablethermostatusershadhighersavingsthannon-programmable.d. UseofAutoawayfeaturehadhighersavingsthanaverage.e. EnergysavingshigherinZone2thanZone1.

1 Ecotopeestimateda2.7Ftakebackintemperatureincrease.ThisanalysisguessedatbaselineindoorsetpointandtriedtocalibratebillingdatawithpreandpostinstallationresultsusingSEEM.HigherbillinganalysispostinstallationcouldalsobeattributedtomoreuseofinefficientERuse,sincethepre-installationsetpointwasnotmeasured.


f. HomesinPortland/MetroareahadslightlyhighersavingsthanSouthernOregonorWillametteValley.

Thisstudydescribedsavingsdifferences,butdidnotattempttoprovidereasonsfordifferences.ThehypothesisforthestudywasthatsavingswouldoccurbecauseWCTfeaturewouldlockouttheresistancestripheatwhenoutsidetemperaturesallowedforefficientheatpumpoperation.2Whilethismayhavecontributedtosomesavings,itappearssensorsandbehavioralchangeswerealsoacontributortoparticipantenergysavings.

CaliforniastudiesonSmallCommercialuseofcommunicatingthermostatsandBuildingAutomationshowenergysavingsover20%,butequipmenttypewasnothomogeneous.StudiesshowthatuseofWCTimprovecustomerprogramparticipationandcapacitysavingsby67to200%.(EnergyInsights,2015)Moreutilitiesareconsideringpricingprogramsasthemeanstoachievingdemandresponseobjectives.Whilethismayfitutilityandrevenuemodels,thesepriceonlyprogramsgetlesscapacitysavings,lessreliability,andcanleadtohighercustomerbills.SeasonalpeakcapacitysavingswithWCTandHEMhavebeendemonstratedforsummermonthsinterritoriesoutsidethePNW.Forexample,Nest’sdemandresponseprogram,calledRushHourrewards,reducedAirConditioningloadby50%for2hourpeakperiodsinTexas,California,(AustinEnergy,2015) (Nest,2013)Theseprogramshadnocustomercomplaintswithonlyahandfulofcustomerquestions.Nestranawinter2015/2016demandresponseprogramatPGE,noresultsavailableatwriting.

2.1.4 Web-enabled communicating thermostats exist for all residential HVAC, though few examples in resistance HVAC and inverter driven heat pumps

TherearesomevendorsofWCTandHEMthatworkwithERHVAC(Sinope,HoneywellRedlink,Aube,Energex,Iotas,Verve)andwithductlessmini-splitheat-pumps(Daikin,Mitsubishi,LG),andonlyoneaftermarketenergymanagementvendorthatwillworkwithboth(PowerWise).WCTs,sensors,andsoftwareareinearlymaturitystageandexpandingintoallHVACsegments.DespiteavailableWCTtechnologywithERHVAC,companieslikeCadet,Nordyne,Evcon,etc.arenotofferingWCTswiththeirHVACequipment.Thepaceofimprovementandadoptionisfast,yetgettingtheseproductsfocusedonenergysavingsinERHVACandDHPwillrequirefurtherstudyandmarkettransformationattention.InthePacificNorthwest,therearenoWCTsinstalledwithERzonal/FAF,orinverterdrivenheatpumps(unlessaveryearlyadoptercustomer).ThisHVACisresponsiblefor66%oftheresidentialheatingloadin2015(1,185aMW)ThissuggestsamarkettransformationopportunityifWCTintegrationcanbeprovencosteffectiveforenergyandcapacity.

2 ThisstudyhasshownthattheNestthermostat,whenusedasanalternativeapproachtoanoutdoorthermometercontrollingthelockoutofresistancebackupheat,canofferconsiderableenergysavings.TheNestthermostatpreventsexpensiveresistanceheatfromrunning,byusingalgorithmstooptimizeenergyuseundergivenweatherconditions.Itisthis“smartalgorithm”featureoftheNestthatmakesitsoattractiveforaprogramlikethis.


77%ofAmericansuseasmartphone,andover50%homeshaveconstantbroadbandservice.

2.1.5 Use of WCTs in residential electric HVAC will provide the region with 226aMW of cost effective energy savings and over 2,000MW of seasonal capacity.

With85%WCTpenetrationonASHPs,and700aMWusein2034,a12%energysavings,asdemonstratedinApexstudy,wouldsave73aMW.ForNon-ASHPelectricHVACweconservativelyestimatea7%energysavingsfromtheuseofWCT.ThisincludesdwellingswithElectricHVAC,DHP,oracombinationofthetwo.forthefollowingreasons:

1. RTFisusing5%savingsonameasuretomoveelectriczonalheatingfrombi-metaltoelectronicthermostats.3ThisRTFmeasureissimplyprovidingimprovedaccuracyonsetpoint,ornarrowingdeadband,anddoesnotnecessarilyincludeprogrammablefeatures.

2. 2002EWEBstudyshowsaverage18%savings(1,475kWh/yr)fromuseofprogrammablethermostatsoverbi-metalwithzonalHVAC.4WCTwilldobetterthanthis.

3. 90%ofthermostatsforzonalHVACarebimetallic.(bigsavingsopportunity)4. ManypeoplepointtoNestsavingswithASHP(12%)ascomingfromlockoutofresistancestrip

heat,butthatisonlyoneelementforsavings.EnergysavingsfromWCTsarefoundinGasFAFandCentralAC.RecentETOStudyfoundNestusewithGasFAFhad6%energysavings.5Thissuggestssavingscomingfromsomethingotherthanstripheatcontrol.

5. InETONestASHPstudy,WCTusehadhigherthanaveragesavingsinmarkets,e.g,.low-incomeandmanufacturedhomes.Thissuggestssavingscomingfromsomethingotherthanstripheatlockout.TheEnergyTrustofOregonexistingbuildingsprogrammanagersuggestedthismakessensebecauselowerincomehomespaycloserattentiontomeasuresthatcanprovide$20/monthofsavings,andtheyhavesmartphones.ThesearealsotargetmarketsforhighpercentageuseofelectricresistanceHVAC.

6. Savingsfrombehavioraltools,e.g.,Opowerarecominginaround2%.Thesetoolsprovideonlysocialinformation.WCTscanprovidemoreinformedfeedbacktohelpconsumerssaveenergy.

7. ThisdoesnotincludeCoolingloadsavings.

With85%WCTpenetrationonNon-ASHPHVAC,and2,260aMWbaselineusein2034,a7%energysavings(guess),Theregioncouldsave153aMW,andover2,000MWinWintercapacity.Thisisinadditiontoa442aMWsavingsthatcouldcomefrommoving85%ofthismarketintoDHPorinverterdrivenheatpumps.(Seetable2forbreakdown)WCTheatingelectricsavings:ASHP73aMW+non-ASHP153aMW=226aMW

3 http://rtf.nwcouncil.org/meetings/2016/04/ 4 http://rtf.nwcouncil.org/meetings/2016/04/ 5 http://assets.energytrust.org/api/assets/reports/Smart_Thermostat_Pilot_Evaluation-Final_wSR.pdf


2.2 Recommendations

Todate,moststudieswithWCTsarewithASHP,centralairconditioning,ornaturalgasfurnaces.WerecommendstudiesthatexamineWCTandHEMinallelectricHVACequipmentandcustomermarkets,includingSF,MH,MF,andsmallcommercial.

WCTs,sensors,andsoftwareareinearlymaturitystageandexpandingintoallHVACsegments.Inadditiontoprovingenergy/capacitysavings,theyalsoprovideoccupants,HVACcontractors,andutilitywithimportantdata,analytics,FDD(FaultDetectionandDiagnosis).OftentimesWCTscomewithothersensors,e.g.,occupancy,outdoortemperature,andabilitytoreceivepricingorutilityinformation.Manufacturersofelectriczonal,FAF,andinverterdrivenHP(DHP)don’tseemtobemovingquickly,oratall,toincorporateWCTintotheirproducts.ThepaceofWCTimprovementandadoptionisfast,yetgettingtheseenhancementsandafocusonenergy/capacitysavingsinERHVACandDHPwillrequirefurtherstudyandmarkettransformationattention.

2.2.1 Market Research and operational details of WCT/HEM

WorkwithelectricHVACsystems,andDHPmanufacturersandunderstandtheirviewstowardWCTusewiththeirproduct.UnderstandbettertheproductdevelopmentdriversoftheelectricHVACmanufacturers,andtheirwillingnesstoworkwith3rdpartythermostats.1. EvaluatemarketopportunityforWCTstofocusontheElectricHVACresidentialmarket.The

RTFissuggestingelectronicthermostatreplacementsforbimetallicforzonalheat.Mostofthecostofmeasureisinstallationonlinevoltage.TimetolookatWCTinsteadofelectronicthermostats.

2. HowisHomeManagementmarket(Nest,Alarm.com,Iris,Wink,etc.)lookingatenergymanagement?WhatstrategiestogetthesehomemanagementsystemstoworkwithresidentialcontrolofHVAC,lighting,otherappliances.

3. DetailedresearchformarketbarrierstoWCTintegrationwithDHPandelectricHVAC.4. LookatbarriersofgettingWCTswithFAF,especiallyinManufacturedHomes.

2.2.2 Lab Studies.

SinceWCTcontrolofERHVACandInverterDrivenHeatPumpsisrelativelynew,itisworthwhileunderstandingsomeofthetechnicalintegrationfeaturesthatwouldleadtoenergysavings.JustasNestfocusonASHPstripheatlockout,theremaybeintegrationbenefits.ForinstanceWCTuseofoccupancyorlearningalgorithmsmightidentifyreasonsforsavings.

1. StudieswithzonalandFAF2. StudieswithInverterdrivenheatpumps,3. StudieswithWCTcontrollingbothERandDHP.

ExaminehowWCTworkversusASHP,andexploretechnical,vendor,andcostissues.


2.2.3 SEEM modeling.

MuchofthesavingsfromWCTinvolvesuseofoccupancyandtemperaturesensors,learninghomeuserbehaviorandpatterns,andbetterequipmentcontrol.SEEMmodelingmaybeabletoconsiderWCTsavingsfromvariousbaselines,andaWCTwouldlooklikeotherprogrammablethermostats.Wedon’tthinkSEEMmodelingcancaptureenergysavingsfromuseofsensors,learningalgorithms,oruserbehavioralchanges.PotentialModelinganalysis:

1. EvaluatetechnicalinteractionsbetweenDHPandsecondaryHVAC,andevaluatingvariouscontrolstrategies.

2. DemonstrateenergysavingsfrombettercontrolstrategieswithvariousHVACequipment.Forinstance,inDHPstudies,occupantsdidnotuseprogrammablefeatures.WCTsmightimprovethiswithimproveduserfriendlinessandfeedbackfeatures.

3. UseSEEMtogeneralizesavingsfromlabtestingdataandfielddata.ThisaspectwasusedinEcotope’sDHPevaluationswhichdidincludebothlabandfieldstudydata.

SEEMmodelingcouldassistprovideenergysavingsestimates,andinformdiscussionswithvendors.

2.2.4 Field Studies

WethinkthatfieldstudiesincorporatingWCTswillbethemostbeneficialtoolatgaugingspecificequipmentandsegmentenergysavings,becauseoftheuseofsensordata,behavioral,andlearningfeaturescannotbeuncoveredinthelab,andcanonlybeguessedinmodeling.

1. ManufacturedHomes.OneyearstudyofenergyandcapacitysavingsusingWCTspecificallyinManufacturedHomemarkets,forbothnewconstructionstandardsandretrofits.UseWCT/HEMvendorsthatcancommunicateandcontrolbothDHP,andFAF.ThoughWCTsarenotoftensoldwithElectricFAF,thereareWCTsthatwillworkwithFAF.Innewconstruction,workwithChristopherDymondandtheNEEMandHPMHstandardefforttodefinestudyparametersandtechnologies.Forretrofitstudy,workwithprogrammanagersatBPA,ETO,andutilitiestodefinetechnologyandstudyspecifics.

InWashington2,500heatpumps(bothASHPandDHP)areinstalledinManufacturedHomeseveryyear.TheStateofWashingtonEnergyOfficeisworkingwithLabor&Industries(L&I)tocommissionandevaluateenergyusagedataonthesesites.ThisdataandmarketaccesscouldbeusedasaresearchprojecttodeterminesavingswithandwithoutWCTs,forASHPandDHP.ThisisalsoanopportunitytoengageL&ItoinstallWCTswhencommissioninghomeswithheatpumpsandelectricresistanceheat.2. Multifamily.OneyearstudyofenergyandcapacitysavingsusingWCT/HEMspecificallyin

Multifamilymarket.UseWCT/HEMvendors(e.g.,Iotas,Energex,Verve,other)toconstructastudyusing3groups(1.controlgroup,2.informationonly,3.Automation,sensors,andcontrol,and4.InformationPLUSAutomation/control).Studywilllooktomeasurethemarginalbenefitofcontrolwhichwillcostmoretoimplement.EQLEnergyhasbegunthefundingprocesswithBPATechnologyInnovation,ETO,andOregonBest.Siteshavebeen


identifiedandtargetgroupsperbuildingare90units.Wewouldliketoalsoperformstudiesonsmallermultifamilydwellings.

EQLvisiteda2015constructedmultifamilybuildingwithCadetwallheatersandinefficientAmanaPTACs.ThereareWCTopportunitiesforsavingsinthismarketwithorwithoutDHP.

3. SingleFamily.OneyearstudyofenergyandcapacitysavingsusingWCT/HEMspecificallyin

SingleFamilymarketelectricallyheatedandcooledwithsomethingotherthanASHP.UseWCT/HEMinsinglefamilyhomesnewandretrofitsthatheatwithER,zonalorFAF.IntegratedInverterdrivenHP,includingductless,shortrunducted,andcentral.StudyofHEM/WCTwith1)DHPand2)zonalheat.LikelyvendorwouldbePowerWiseorothervendorbecauseWCT/HEMtechnologytomanageDHPandZonalHeatisonlyintheaftermarket,atthistime.Thestudywouldneedtobeadetaileddiveintothecommunicationtechnologyandintegrationofmorethanonevendor’sHVAC.ThisstudywillbedictatedbyavailabletechnologyandcooperationofDHPvendors.

3a. WSUEnergyOfficesubmittedafundingrequestthroughBPATIthatlooksatasampleof

similarlysituatedtownhomesinKingCounty.Studyincludeshomeswithexistingzonalheat,andinstallingunitswithshortrunductedminisplits(DMS),andsomewithDuctlessMiniSplits(DHP).

EQLEnergyproposedaddingtheWCTstudyfeaturethatwillworkwillallHVACtypestoexaminemarginalenergysavingsandpeakcapacityreductions.ControlsforERheatersinhomeswheretheyarenottheprimaryheatingsource,inconjunctionwithaDHPinstalledinthemainlivingarea.WSUproposestoworkwithKCHAandJohnsonControlstoevaluateweb-controlledthermostats(WCTs)aswellaspotentiallysimplerandlower-costnon-WTCabilitytocurtailERusebasedonoutsidetemperature,acceptableoccupantbedroomcomfortswings,and/orbedroomzoneoccupancy.Theresultsofthatevaluationwillinformwhatisusedinthe10casestudyhomes.

4. SmallCommercial.OneyearstudyofenergyandcapacitysavingsusingWCT/BEM

specificallyinSmallCommercialmarketthatuseelectricresistanceHVACorresidentialHVAC.Marketsincludelodging,eldercare,smalloffice/retailwithElectricHVAC.VendorswouldincludeIotasandEnergex.CostsforthesesystemsareoverallhigherthanresidentialWCT($750-$1,200),butsavingsandcapabilitieswillalsobehigher.Commissioningandusertrainingisimportanttoachieveenergysavingsandimproveuserperceivedcomfort.6

6 http://wcec.ucdavis.edu/wp-content/uploads/2014/10/OutcaultACEEE_Thermostats.pdf


3 Background

3.1 Market Size and Energy/Capacity Savings Potential

3.1.1 Market Size

Thereareabout2MillionelectricallyheatedresidentiallivingspacesinthePacificNorthwest(singlefamily,manufacturedhomes,andmultifamily).Thesedwellingsuseabout1,950aMW/yr,with1,185aMWcomingfromresistanceheating(zonal,plugin,andFAF).A2015Navigantreportestimatedthatuseofresistanceheatingwillcontinuetoincreaseto2,260aMWby2034,a1%annualincrease.UsingthisdatatoforecastincreaseindwellingswithelectricHVACrevealsvaluesusedinouranalysisandshowninTable1below.Table1:MarketforElectricHVAC(non-HP)inthePacificNorthwest

(1)2015Illume,MPER4forNorthwestDuctlessHeatPumpInitiative(numberbasedon2010RBSAEcotopeSep18,2012)

http://neea.org/docs/default-source/reports/ductless-heat-pump-market-continues-to-increase-dhp-mper-4.pdf?sfvrsn=12

(2) 2012EcotopeRBSAsummary

http://neea.org/docs/reports/residential-building-stock-assessment-single-family-characteristics-and-energy-use.pdf?sfvrsn=8

(3) 2015ETONeststudywithASHP(12%heatingload,coolingwasnotpartofstudy)

http://energytrust.org/library/reports/Nest_Pilot_Study_Evaluation_wSR.pdf

(4) 2014NEEARBSAforMHandMF

http://neea.org/resource-center/regional-data-resources/residential-building-stock-assessment

(5) 2014EcotopeDHPFinalSummaryreportimpactandprocessevaluation,Ecotope

http://neea.org/docs/default-source/reports/e14-274-dhp-final-summary-report-(final).pdf?sfvrsn=8

48%ofpotentialsavingsfromDHPwest,23%savingsineast,becauseofsecondaryheatsourcelose30-40%ofsavings

(6) 2015Navigant,ResidentialInveter-DrivenHeatPumpTechnicalandMarketAssessment:

https://neea.org/docs/default-source/reports/residential-inverter-driven-heat-pump-technical-and-market-assessment.pdf?sfvrsn=4

WethinkthereisamarkettransformationopportunitytoacceleratetheintegrationofWCTsforbothDHPandresistanceelectricheat.WCTsalreadyare21%annualsalesofthermostatsandareexpectedtobeover50%by2020.(Talpur,2015)Weonlyfoundonemanufacturer,Daikin,sellingDHPwithWCTs

Electric HVAC (non-heatpump)Units SF MH MF Total SF MH MF Total

ElectricHVAChomes Units 728,047 483,920 750,900 1,962,867 1,092,071 725,880 1,126,351 2,944,301

zonal Units 505,066 9,678 600,720 1,115,465 757,599 14,518 901,081 1,673,197

FAF Units 222,981 309,709 15,018 547,708 334,472 464,563 22,527 821,561

DHPinstalled(basedonpenetration) DHPunits 97,149 3,871 22,527 123,547 928,260 616,998 957,398 2,502,656

DHPPenetration % 13% 0.8% 3% 6% 85% 85% 85% 85%

MeasuredDHPSavings

AverageAnnualelectricspaceheat kWh 8,116 8,848 3,900

ActualsavingsperhousewithDHP kWh 1,900 2,071 844

ActualDHPsavingspercentageofHVAC % 23% 23% 22% 23% 23% 22%

TotalPossiblesavingsifallHP 48% 62% 45% 60% 62% 60%

2015 2034Source(4)&(6)

(4)&(6)

(4)&(6)

(4)

(1)

(2)&(4)

(5)

calc

(5)


(DaikinresellstheEcobee).Wefoundafew3rdpartyWCTequipmentprovidersworkingwithresistanceheat(Sinope,Honeywell/Aube,andPowerwise),andafewworkingwithmultifamily/lodging(EnergexandIotas).AnotherinterestingresearchfindingwasthatresistanceheatingmanufacturerCadethasoveronemillionunitsinthePNWandstillsells200,000units/yrofresistanceheatersintheNorthwest,primarilywallheaters.EQLvisiteda2015constructedmultifamilybuildingwithCadetwallheatersandinefficientAmanaPTACs.ThereareWCTopportunitiesforsavingsinthismarketwithorwithoutDHP.

3.1.2 Energy and Capacity Savings Summary

BasedonseveralstudiesonexistingDHPinstallationswethinkannualaverageMWsavingsforDHPinstallationstobeabout24aMW/yr.IfthesesameinstallationshadWCTthatcontrolledthesecondaryHVAC(zonal,FAF)weestimateanimprovedsavingswouldbe7aMW.Thisrepresents7%savings.Ifwelookoutto2034whereresidentialelectricHVACisexpectedtoincreaseandWCThas85%marketpenetrationofelectricHVACtheannualsavingswouldbe153aMW.SeeTable2ThissavingsislookingatWCTuseforallERHVACandDHPs.UsingEcotope’scalculatedenergysavingsanda85%stockpenetrationthesavingspotentialis442aMW/yr.Table2:EstimatedEnergyandCapacitySavingsfromWCTusewithDHPandSecondaryHVAC

EnergySavingsResearch(Ecotope2014)StudiesonASHPsavingsfromuseofWCTs(NestandHoneywell)showaveragesavingsbetween7and20%,whichgenerallycomefromavoidingorreducinguseofstripresistanceheatpresentinmostASHPs.(ApexAnalytics,2014)WeexpectWCTstoachieveanaverageof7%savingswithHVACotherthanASHPandwillbedependentonhousingstockandcustomerbehaviors.RegionalDHPinitiativesavingsestimatesarebeinginformedbystudiesconductedbyEcotope,RTF,ETO,andBPA.The2014EcotopeFinalSummaryonDHPImpactEvaluationlookedat3,899DHP

Electric HVAC (non-heatpump)Units SF MH MF Total SF MH MF Total

2015 2034

DHPPenetration % 13% 0.8% 3% 6% 85% 85% 85% 85%

AnnualEnergyUsageandSavingsCalculationsUsageElectricResistanceHVAC aMW 675 489 334 1,498 1,018 738 504 2,260

SavingsPotentialifDHP100%marketand

100%ofHVAC aMW 324 304 150 778 611 459 303 1,372

ActualSavings:DHPsavings23%xmarket

penetrationaMW 21 1 2 24 203 147 93 442

%savingswhenaddingERcontrolsorWCT 7.0% 10.0% 7.0% 7% 10% 7% guess

EstimatedsavingsbasedonguessforER

controlorWCTaMW 6.3 0.4 0.7 7 61 63 30 153

CapacitySavingsifWCTonDHPandSupplementalWinterCapacity kW 1.0 1.0 0.5 1.0 1.0 0.5

SummerCapacity kW 0.5 0.5 0.5 0.5 0.5 0.5

WinterCapacity MW 97 4 11 112 928 617 479 2,024SummerCapacity MW 49 2 11 62 464 308 479 1,251


installationswhichdisplacedelectriczonalheating.Averagesavingsinsinglefamilyhomeswere1,900kWh/yrfromabaselineaverageof8,116or23%.DHPCOPsinPNWaverage3witharangefrom2to4.SavingswerereducedfromCOPorlabresultsbecause:

1. Homescontinueduseofsecondaryheatwas30-40%.SeeFigurebelowthatshowsuseofsupplementalheatcontinues.Dependingonhowthermostatsareset,thesupplementalcouldevenbecometheprimaryheatsource.HavingathermostatthatcontrolbothwouldhelputilizeDHPmoreoften.

2. Savingswerealsoreducedby20%basedonbehavioralchangesthatincreaseduse.Ecotopeinferredthisfromdataanalysisbetweenameteredsampleandbillinganalysis.RTFhasrecognizedthenon-energybenefittotheDHPMeasureforincreasedcomfort($40/yr).EcotopefoundincreasedusewithDHPforfollowingreasons:

a. Classictakebackcustomersturnedupsetpoint(thiswasdemonstratedviapreandpostenergyuseforspaceheating)

b. Customersleftheatonalldayandnightc. Unoccupiedheating

Figure1:DHPSupplementingZonalElectricHeat

PeakDemandSavingsInordertoachievepeakdemandreductionsinhomeHVAC,itisimportanttoincludeWCTsandcommunicatingcontrolstoallheatingcircuits.Thesedevicesautomatetheprocessofparticipatinginrateorloadcontrolprogramsandleadstohigherdemandsavings.


LBNL2015reportfoundthatpeakdemandreductionsforpricingprogramsusingWCTswere27%to45%,whilewithoutWCTs(-1%to37%).WCTs“lowerthetransactioncostsassociatedwithrespondingtopricesandcriticalpeakeventsbymakingiteasierforcustomerstoaltertheirelectricityconsumptionatspecifiedtimes.”(LBNL,2015)ASMUDWCTpilotevaluatingenergyandcapacitysavingsinmultifamilyfoundcapacitysavingsof29to35%whentiedwithapeakpricingprogram.(ACEEE,2014)Thisiscomparedtoa5-7%capacitysavingswhencustomersareonpeakpricingprogramandeducation.TheNPCCRegionalTechnicalForum(RTF)hasdiscussedthecapacityandenergysavingsfromDHPseeFigure2below.

Figure2:2014EnergyandCapacityforDHP,NorthwestPowerandConservationCouncil

3.1.3 Savings by Equipment, Sector, and Region

EquipmentTwostudiesbyEcotopeevaluatedpilotsforSinglefamilysupplementingzonalheatandSingleFamilyandManufacturedhomessupplementingelectricforced-airfurnaces(FAF).Bothstudiesshowedthatsavingswerereducedby30-40%fromtheuseofsecondaryheatsources.ThestudyonFAFfoundsavingsofabout5,500kilowatthours(kWh)resultingfromtheuseofDHPs.Thedriverofthesesavingswastheoccupant’sFAFandDHPcontrolstrategy:occupantswhomadetheDHPtheirprimaryheatsourcesavedconsiderablymoreenergythanthosewhoretainedtheFAFastheirprimaryheatsource.ThesavingsresultedfromacombinationofDHPefficiency,reducedenergywastefromductlosses,andachangefromheatingthewholehousetokeepingthemainpartofthehousecomfortablewiththeDHP.InventoryofheatingequipmentwasprovidedinNavigant2015andsummarizedinTable3below.


Table3:ElectricHeatingUsebySystemTypeandSector(Navigant2015)Primary Heating System Type Total Load

(aMW) Single Family Manufactured Multifamily

Air Source Heat Pump 478 83% 17% 1% Baseboard Heater 638 66% 1% 33%

Boiler 19 100% 0% 0% Dual Fuel Heat Pump 41 100% 0% 0% Ductless Heat Pump 55 92% 8% 0% Forced Air Furnace 484 38% 60% 2% Ground Source Heat Pump 25 100% 0% 0%

Packaged Terminal Air Conditioner or Heat Pump

8 0% 0% 100% Plug-In Heater 44 78% 22% 0%

Source: Navigant 2015 Analysis of RBSA data SingleFamilyThereare728,047singlefamilyelectricallyheatedhomes,ofwhich505,066havezonalresistanceheat,and222,981withFAF.(Illume,2015)NEEAhasanambitiousgoalof85%ofthesehomeswithDHPby2028,whichmaybemovedoutto2034,basedonrecommendationsby(Illume,2015).Sincethe2008-2009largescalePNWDHPpilottherehavebeenlabtests,fieldmonitoring,billinganalysis,costanalysis,impactandprocessevaluations(Ecotope),aswellasregularmarketprogressevaluations(Illume).Thispreviousworkhasbeenoursourcetoestimatemarketsizeandopportunityforbettercontrolandintegrationwithsecondaryheatingsources.13%ofSFnewconstructiongetselectricheating.(RLWAnalytics,2007)ThegoalforDHPsupplementalheatistoreduceuseofzonalheatingasshownin


Source: Navigant Analysis ManufacturedHomesFromTable2above,Manufacturedhomescomprise22%oftheNorthwest’snewconstructionmarketelectricload(approx.2,000to4,000units/yr)and14%oftheexistinghomesintheNorthwest.(NavigantMarketAssessment,2015)Almostallnewmanufacturedhomesareshippedwithelectricforcedairfurnaces,dominatedbytwovendorsEvconandNordyne(Nortek).Thisequipmentcancost$200fora16kWunit,plus$100forducting.ThismarketwouldrequireinterventiontogetmanufacturerstomovetoDHPorASHP,orincludingWCTs.February2016theRTFapprovedtheUES(UnitEnergySavings)measuretouseDHPinManufacturedhomes.AtitsFebruary2015meeting,theRTFagreedwiththeprofessionaljudgmentthatsavings,cost,andlifearenotsignificantlydifferentthanthesavings,cost,andlifeforthesamemeasureinsinglefamilyapplications.Thesinglefamilyresultswereuseddirectlyforthismeasure.Multifamily(MF)andCommerciallodging WethinkinMFtherearesimilarsavingpercentagesinmodifyingcustomerbehaviorandavoidinguseofsecondaryorprimaryheatsourcesthatuseelectricresistanceorPTAC(PackagedTerminalAirConditioner)units.Theperunitsavingswillbelowerthansinglefamilyormanufacturedhomes,butopportunitiesexisttocombinesavingsforallunitsatagivenlocation.Thatsaid,ifmarkettransformationeffortsweresuccessfulincombiningcontrolofDHPandsecondaryheat,thenMFcouldtakeadvantageofimprovedenergysavings.Ecotope2012foundinMFinstallationsofDHPs824kWh/yrsavingsinunitsfrom400-1,100sf.(Ecotope,2012).Wealsorecognizethatmultifamilyisalargeopportunitytoachieveenergysavingsthroughbettercontrolsofbaseboard/wallheatandPTACunits,withorwithoutDHPs.Aspartofthisresearchpaper,

612

413

281

147 127

76 69 33

9 19 4 2

Washington Oregon

Single Family Manufactured

Idaho

Montana

Tota

l Ele

ctric

Hea

ting

Load

(aM

W)

Figure3:ElectricHeatingbySectorandState(Navigant2015)


EQLEnergywalkedthrougha500-unitPortlandapartmentbuildingthatwasbuiltin2015.TheHVACincludedinefficiencyelectricresistancePTACandwallheatersandelectricwaterheat.Technologytoachieveenergysavingsinhotelandmultifamilyaregenerallybasedonoccupancysensors.AccordingtotestingdonebyBCHydroandPacificGas&Electric,EnergexsystemsreduceHVACandlightingcostsbyupto40%,aswellasincreaseequipmentlifeanddecreasenoise.SeeTable4summarizingstudieswiththesetechnologiesshowaverageannualenergysavingsof900kWh/yr.EQLhasworkedwithEnergexonaprojectatUniversityofBritishColumbia-Vancouver.Table4:OccupancySensorEnergySavingsinMultifamily

BPAlookedathoteloccupancysensorsavingsin2010and2011andfoundanaveragesavingsof12%,fromturningofflightsandHVAC.(BPA,2010)InspeakingwithBPAmanager,ErikBoyer,BPAdidnotpursueaprogramofOccupancyControlSensors(OCS)forhotelsbecausethebaselinestudyshowedthathotelstaffwouldturnoffroomHVACandlightsaftercleaning.Mr.Boyerfeltthatthistypeofcontroltechnologymaybecosteffectiveinapartments,collegeresidence,ormultifamily.USDOEhadamorecomprehensivereportthatfoundincreasedsavings,butincludedareasnotrelevanttoNorthwest.(USDOE,2012)NewConstructionFroma2007reportonSingleFamilyresidentialnewconstruction,itappearsthat13%ofnewhomeshaveelectricheatininORandWA.Navigant2015,basedonRBSA,estimatedthatelectricresistanceheatingwillcontinuetoincreaseinuseby1%ayearfrom1,185aMWtodayto2,260aMWby2034.

Table5:2007studyonSFNewConstruction,heatingtype

State Gas Electricity Pellets Propane n % EB % EB % EB % EB

ID 90% 5% 3% 3% 0.4% 0.6% 6% 4% 179 MT 100% - - - - - - - 18 OR 82% 6% 17% 6% - - 0.5% 0.8% 178 WA 77% 5% 16% 4% - - 6% 3% 229

Overall 82% 3% 13% 3% 0.1% 0.1% 4% 2% 604

Washingtonenergycoderequiresthatheatpumpsmusthaveoutdoorthermostatsandlockoutuseofresistanceheatwhentemperatureisabove35F.Thisseemsanopportunitytodothiswheneverresistanceheatingisbeingspecifiedinanysectornewconstruction.SellingmainlivingareahastohaveDHP.Soahomewith4heatingareaswouldhave3resistanceheatareasstillusingresistanceheat.

Location units kWhsavings perunitsavings# kWh/yr kWh/yr-unit

ConestogaCollege 275 150,000 545

UnivTowers 470 210,077 447

WeinbrennerPlace 72 120,889 1,679

CreeburnLakeLodger 600 573,271 955

http://www.nrgee.com/energex-inc-removes-wasted-energy-from-empty-rooms/


SmallCommercialWealsonoticedfromthe2014CBSAthatthereareseveralCommercialsectorsthatareappropriateforWCTandBuildingEnergyManagementsimilartoresidential,e.g.,lodging,residentialcare,universityresidences,schools,andsmalloffice/retail.SeeFigurebelowfromCBSA.LargerCommercialBMShaveenergy/capacitysavingsopportunities,butthetechnologyisveryspecifictosectorRetrofittingsmallcommercialwithDHPscanhavetremendousenergysavings.ABPAsponsoredreportbyEcotopefoundanaverageof4,185kWh/yrenergysavingsatsixsites.ThisreportfoundthatmorethanhalfthesiteshadDHPprovidingmorethan90%oftheheat.ThisisincontrasttoresidentialDHPretrofitswhereDHPonlyprovided45-80%ofthespaceheat.(EcotopeBPA,2012)WedothinkthataswelearnmoreaboutsavingsfromHEMandWCToptimizationandmanagingcompressorcycles,thattherewillbesavingsinthissector.EQLEnergyworkedwithCypressEnvirosystemstoreplacepneumaticthermostatswithcommunicatingthermostats.Ourstudyfocusedondemandresponseandwedidnotmeasureenergysavings.


Figure4:2014CBSAHVACEquipmenttype


3.1.4 Regional HVAC Controls and DHP Measures and Research

ThermostatsMeasuresETOprovidesa$50rebateforNestthermostatswithASHP,FAFelectricorgas.(ETO,2016)Thiswassupportedbypilotstudiesthatshowed12%electricsavings,andundocumentedgassavings.PacifiCorpandPSEinWashingtonprovidesrebatestocustomersforinstallationofWCTs.(PacifiCorp,2015)CurrentlytheRTF’sonlyresidentialthermostatandcontrolmeasureisReplacementofbi-metalthermostatswithelectronicthermostatsinnewandexistingsinglefamilyhomes.Lineandlowvoltagethermostatsareeligible.Measuresspecificinclude:Costis$235,lifeof15yrs,newandexistingconstruction,benefitcostratioispositiveinHeatingzone2and3,andneutralinHeatingZone1.WeexpecttheRTFtoconsideraddingWCTsasameasureforASHP,andwouldliketopreparemarkettouseWCTsforDHPandelectricresistanceheating.RTFhasnotaddedcommunicatingthermostatstoUESmeasures.TheystillhaveanelectronicTstatreplacementforbi-metalsavings/cost,andtheyareexaminingsavingsfromresidentialbehavior,e.g.,Opower.WearesurprisedthatWCTshavenotbeenaddedtoRTFmeasures.Table6:RTFMeasureonElectronicTstatreplacementforbi-metal(2012)Annual Savings Assumptions 5%

Heating Climate Zone

Pre80 Post ResWX Use (kWh)

Annual Savings (kWh)

Average Cost/Dwelling

Heating Zone 1 8,716 436 $235 Heating Zone 2 11,941 597 $235 Heating Zone 3 14,453 723 $235 Based on EWEB's Comfort STAT program. Average of 5 Thermostats per dwelling. RTFResidentialBehaviorRTFhasasubcommitteeonresidentialbehaviorsavingsandiscurrently(2016)exploringUESmeasure.(RTF,2016)Mostresidentialbehaviordiscussionsarearoundgenericmeteringfeedback,e.g.,OPower.Thesetoolsshowwholehousesavingsof1-3%.Forinstance,SeattleCityLightandPSEstudiesfound1.7to2.0%savings–about200kWh.Thistypeoflowvaluegenericinformationishardtocapturesavingsandthesubcommitteeisdebatinghowtoproceed.WithregardtoHVAC,WCTsprovidehighervalueinformation,sensors,andlearningmethodsthatdemonstratehigherpercentagesavingsthanmerelyrepackagedbillingdata.RTFWCTOptimizationLayerRTFhasaproposal(Mar.2016)fromWeatherBugtoconsideraddingacontrolsoptimizationlayertoWCTsbasedonweatherdata.JoshRushton,RTFanalyst,hasreachedouttoindustryparticipants,e.g.,RobertWeber(BPA),PaulSklar(ETO),BobbetteWilhelm(IdahoFalls),andKenAgnew(DNV-GL)toconsidertheproposal.InourviewRTFshouldconsideramorecomprehensivelookatWCTs,disaggregatedin-homeinformationandcontrolsystemsforenduses,e.g,waterheat,lighting,EVCharging,pool/spapumps,etc.


WethinkthatfocusingontheoptimizationlayerisimportantandthatWeatherBugmaybeagoodplatformforcommunicatingwithcertainWCTs.Theypromoteopenstandards,whichisnotthecasewithallWCT(e.g.,Nest).ETOCurrentlyETOhasaDHPincentivefornewconstructionandRTFisevaluatingthismeasure.NEEAisthebestsourceofdataonDHPforexistinghomes.CoolingWethinkthatusingDHPswithWCTscanimprovebothenergyandcapacitysavingsinthesummer.Wedidnotestimatethesavingsvaluebecausewecouldnotfindanydetailedreportsthatdiscussedenergysavingsfromcooling.IncaseswhereDHPsareusedtodisplacewindowshakersorsmallairconditioners,coolingsavingswillhappen.Yettheelectricsavingsfromcoolingisstilllessthan10%ofheatingsavings.OfcourseaddingaDHPwheretherewasnopreviousACincreasesenergyuseandprovidesaddedbenefits.WewouldarguethatacrossthePNW,summerpeaksareincreasingduetomoreuseofACandhigherCDD.SupportingtechnologythatassistsinreducingACcapacitywillbenefittheregion.SeveralstudiesfoundthatDHPseitherdisplacedlessefficientcoolingorwerenotusedmuchinlocationsthatdidnothavepreviousAC.

Thereisnoapparentevidence,basedonthecurrentdata,thattheinstallationofDHPshascreatedasignificantnewcoolingload.Sitesthathadanotablepre-installationcoolingloadevidentinbillscontinuetohaveitinDHPusage,butthesitesthatdidnothavemuchcoolingbeforedonotseemtousetheirDHPsmuchincoolingmode.(Ecotope,2010)

WashingtonCodeWashingtonbuildingcodesrequiresresidentialbuildingswithERHVACtoaddaDHPtolargestzoneindwelling.ThismeansthatthereisanopportunitytoimprovesavingsbyfindingcontrolsandsetupproceduresthatcouldlockoutERHVAC.WithR403.1.1thereisanopportunitytoincreasesavingsbyinstallingWCTinsteadofprogrammabletstat.

R403.1.1Programmablethermostat.Wheretheprimaryheatingsystemisaforced-airfurnace,atleastonethermostatperdwellingunitshallbecapableofcontrollingtheheatingandcoolingsystemonadailyscheduletomaintaindifferenttemperaturesetpointsatdifferenttimesoftheday.EXCEPTIONS:1.Systemscontrolledbyanoccupantsensorthatiscapableofshuttingthesystemoffwhennooccupantissensedforaperiodofupto30minutes.2.Systemscontrolledsolelybyamanuallyoperatedtimercapableofoperatingthesystemfornomorethantwohours.

WithR403.7.1thereisanopportunitytoprovideimprovedsavingsbyusingWCTthatworkswithbothDHPandsecondaryheat.


R403.7.1Electricresistancezoneheatedunits.Alldetachedone-andtwo-familydwellingsandmultiplesingle-familydwellings(townhouses)uptothreestoriesinheightabovegradeplaneusingelectriczonalheatingastheprimaryheatsourceshallinstallaninverter-drivenductlessmini-splitheatpumpinthelargestzoneinthedwelling.Buildingpermitdrawingsshallspecifytheheatingequipmenttypeandlocationoftheheatingsystem.

WithR403.1.2thereisWCTopportunitytoprovideimprovedsavingswhilemanagingstripheatlockout.

R403.1.2Heatpumpsupplementaryheat(Mandatory).Unitaryaircooledheatpumpsshallincludecontrolsthatminimizesupplementalheatusageduringstart-up,set-up,anddefrostconditions.Thesecontrolsshallanticipateneedforheatandusecompressionheatingasthefirststageofheat.Controlsshallindicatewhensupplementalheatingisbeingusedthroughvisualmeans(e.g.,LEDindicators).Heatpumpsequippedwithsupplementaryheatersshallbeinstalledwithcontrolsthatpreventsupplementalheateroperationabove40°F.Atfinalinspectiontheauxiliaryheatlockoutcontrolshallbesetto35°Forless.

3.2 Residential Electric HVAC products and controls

WCTsalreadyhave21%annualsalesofthermostatsandareexpectedtobeover50%by2020.(Talpur,2015)However,WCTsareprimarilybeingusedwithASHP,gasfurnaces,andcentralairconditioners.

3.2.1 Only a few DHP vendors operate with WCTs

DHPmanufacturersarebeginningtoincludeWCTsintotheirproduct,Daiken,Fujitsu,Mitsubishi,Panasonic,LG,etc.Theyaredoingthistorespondtocustomerpreferences,andenergysavingshasnotbeentestedorproven.

1. DaikinresellsEcobeewithsomeoftheirDHPs.TheycallittheEnvi.2. PowerwisehasiPhoneandAndroidappsareavailableforcontrollingthemini-splitheatpumps,and

remotelymonitoringtheirenergyuse.ItsupportscontrolsforMitsubishi(includingMrSlim),Fujitsu,Daikin,Panasonic,LG,andSamsungmini-splitheatpumps.Figure5showsagraphicofPowerWisesystemworkingwithDHPandconventionalHVAC.

3. FujitsuhasaWifienabledmoduleandthermostat.http://www.fujitsugeneral.com/wifi.htm


Figure5:PowerWise2015WCTformini-splitsandotherHVAC

WCTwithDHPandresistanceheatingisalimitedgroupofvendors.CurrentuseofWCTwithDHPandzonalheatinthePNWisnearzero.Thedevelopmentstageisearlyandisfacedwithmarket,cost,technical,andcommercialbarriers.a. DHPwithfullyintegratedWCT(methodA)

TwoDHPmanufacturersthatweareawareof(DaikinandMitsubishi)haveworkedwithWCTvendors(EcoBeeandHoneywell)tointegratecontroloftheDHPwiththeWCT.TheseproductsareavailablefromDHPinstallers.ItisnotknownifthisconfigurationimpactsenergyefficiencycomparedwithtraditionalDHPcontrolsnortheextenttowhichfurtherintegrationworkbetweenthesevendorsisoccurring.BecauseonlytwoDHPvendorshaveadoptedthisapproach–eachwithasingleWCTvendor–significantadditionalmarketdevelopmentwouldneedtooccuriftheDHPsegmentofresidentialHVACmarketadoptsitasstandardpractice.

b. DHPintegrationwithWCTusingdrycontactterminalbinaryinput(methodB)weareawareoftwovendors,MitsubishiandLG,thathaveincorporateddrycontactterminals.Weunderstandthisallowsthemtoworkwithmostthermostats(includingWCT)using24Vcontrols.ThisapproachisalsoatanearlystageindevelopmentbecauseonlytwoDHPvendorshaveadoptedit.ItisnotknowntheextenttowhichtheuseofbinarycontrollogicwithDHPswilldegradeenergyefficiency,ifatall.Oneoutcomeofthisstudywillbetoassessthisquestion.AdditionallearningsfromthisstudycouldassistNEEAindeterminingwhereleverpointsmayexisttoengageinmarketinterventionwithDHPandWCTvendorsandidentifyingspecificaspectstoconsiderwithregardtointegrationmethode.g.,whetheroneshouldbeprioritizedovertheotherandwhy.WearealsounsureifthismethodallowscontrolofsecondaryHVAC.


c. WCTcontrolofsecondaryelectricresistanceheat+DHPMostDHPinstallationsretainorincludesomeelectricresistanceheatingsysteminthehouse.AddingWCTcontroltothisheatsourcewillhavebothenergyandcapacitysavings.Becausesignificantsavingshavebeenshowntooccurthroughcontrolofresistanceelementsinair-sourceheatpumps(EnergyTrustNestHeatPumpControlPilotEvaluation),connectingWCTsthatareinstalledincustomerhomeswithanyresistanceheatlocatedinrelevantlocationsisanobviousopportunity.Thiscapabilityisavailabletodayonlyasahomeenergymanagementsystemorexpensiveretrofitofexistingsecondarycircuitsandin-linevoltagecontrols.Significantmarketdevelopmentislikelytobeneededbeforethisconfigurationisstandardpracticeorcosteffective.PartofourprojectproposalistoassessthefeasibilityaswellasenergyandcapacitysavingsfromincorporatingzonalresistanceheatcontrolwithaWCT/DHPinstallation.

3.2.2 There are a handful of WCTs that work with electric zonal and FAF, and three aftermarket WCTs that work with both DHP and resistance HVAC.

WCTsarenotwidelyusedforDHPorelectricresistanceheating.TheaftermarketWCTsinthisspace,andoftenfromsmall,sometimesstartup,companies.ThistechnologyisnotbeingdeployedinthePNW.

WCTsthatworkwithresistanceheatingandDHPsInclude:a. PowerWiseb. Pebble.http://www.minisplitwarehouse.com/product/mini-split-wifi-thermostat-controller-

with-7-day-schedulec. Ecobee(calledEnvibyDaikin).IntegratedwithsomeDaikinunits.Ecobeeisnotinvolvedin

productdevelopment.TheyjustsellatstattoDaikin..ListofWCTcompaniesisgrowingandincludes:Nest,Ecobee,Emme,Venstar,MountainLogic,Ecofactor.(WSUEnergyOffice,2012)Sinope,Honeywell,Emerson,Enerjoy,MagnumEnergySolutions7etc.

3.2.3 Resistance Heating Manufacturers

WeresearchedandspokewithfirmsinboththeelectriczonalandFAFmarket.ThisgroupdoesnotappeartomovingquicklytowardsWCTofferings.Thereareseveralaftermarketsolutions,buttheHVACmanufacturerswespoketofeltWCTpricepointistoohighfortheirmarket.Zonalheatincludes:Cadet,QMark,Dimplex,andEnergyJoy,8WespokewithCadetwhoestimatestheyhaveover1MillionunitsinthePNW,andsell200,000unitsperyearinthePNW.Thisequipmentisclearlyrelevantnowandintothefuture.Theyhavecreatedmoreefficientwallheaterswithuseoffans,anddoincludeprogrammablethermostatsfromHoneywellintheequipmenttheysellandsupport.TheydonotofferWCTandhavenoneartermplans.

7 http://www.magnumenergysolutions.com/uploads/Mx-PFC-E02036.pdf 8 http://baseboard-heaters-review.toptenreviews.com/


ElectricFAF,e.g.,JohnsonControls,whomarketsColemanFAFunderlicensebyYork.Nordynebrandedundernamese.g.,Frigidaire,Maytag,Broan,Intertherm,andMiller.NordyneInc.8000PhoenixPkwy.O'Fallon,MO63366-3827(636)561-7300GettingWCTstoworkwithFAFequipmentismucheasierthanzonal,orlinevoltagecontrols.Thiscouldbedoneinnewconstructionoraftermarket.

3.2.4 What benefits other than saving electricity do WCTs provide this market?

WCTsprovidemultiplecustomerbenefitsincluding:1. Convenienceofusingasmartphoneorotherweb-enabledinterfacetomanagethethermostat.2. Detectandinformofequipmentissuesormaintenanceneeds.3. Learningfeaturesthatfocusonusercomfortandenergysavings.4. Informationandcommunicationwithotherhomedevices,e.g.,smokealarms,camera

monitoring,waterheater,etc.5. WCTsprovideutilitywithdata,communicationandcontrolfeaturesfordemandandpricing

programs.WCTsprovideHVACinstallersandequipmentinformationregardingHVACequipmentperformanceandsignalmaintenanceneeds.(Informationmayleadtobehavioralchangesthatsaveenergy–requiresmoreresearchinthismarket)

6. Forcedairfurnaces.Themarketwillberetrofitsandreplacementelectricheatingsystems.7. Abilitytoreceiveutilitycommunicationre:pricingorgridneeds.(demandresponse)8. WCTswithhomeenergymanagementhavemanyotherbenefits,includingotherenergysavings

approaches,e.g.,lighting,waterheat.HEMbenefits.CleaResulthasdoneseveralsurveysthatsummarizesotherbenefitsofHomeEnergyManagementsystems(WCTbeingoneelement).Theseinclude:

1. Automatedenergysavings(i.e.applianceknowstoturnonwhenenergyratesarecheapest,onlyapplicableinareaswithtime-of-use(TOU)rates)-53.2percent

2. Enjoyingamorecomfortablehomethat“learns”heating&coolingpreferences-49.8percent3. Usingsmartphoneappstocontrolthehomewhileaway(lights,heating/cooling,etc.)-48.6

percent.4. Improvingtheenvironmentwithdecreasedenergyuse-48.2percent.5. Receivingalertswhenappliancesneedattention(waterheater,airfilter,furnace,etc.)-47.2

percent

3.2.5 What limitations does the product have that a typical customer may not expect?

TheselimitationswerediscoveredintheEnergyTrustofOregonNeststudyin2015.9a. Equipmentincompatibility.Atpresent,customerswithDHPs,andzonalheatcannotgetoffthe

shelffunctionalitywithWCTs.b. Wifiandrouterissues.IfWCTuseswifi,thentheirusermayrunintotechnicaldifficulties,e.g.,

passwords,incompatibilitywithrouterorotherconnectivityissues,can’tusewithhotspots,

9 http://energytrust.org/library/reports/NestPilotStudyEvaluationwSR.pdf


SomeWCTsareincompatiblewithRouters.Signalstrengthatthermostatlocationistooweak.(Thisisbeingaddressedwithproprietarycommunicationprotocols,e.g.,Weave,Zigbee,Insteon,Z-wave,Emo)

c. WCTtechnicalandwiringissues.WCTsarerelativelynewandwillexperienceerrors.DependingontypeofHVAC,wiringmayneedtochange.

WCT(Web-enabledcommunicatingthermostats)capabilitiescurrentandemerging:Ecobee,Nest,Honeywell,DHPvendors,etc.DualControloptionsforotherHVAC:a)zonalelectric,b)ForcedAirFurnace,and3)hearthheaters:Auberelays,Energex,Nest,Powerwise,etc.

3.3 Gaps and market barriers to adoption of WCT and HEM with electric resistance HVAC and DHP

3.3.1 Gaps and market barriers to potential energy and capacity efficiency

WCTsarerelativelynewandthevendorsofDHPsandzonalheathavejustbeguntoaddresstheincreasingcustomerinterestinusingWCTs.Weseemarketbarriersincluding:a. CostofWCTsmoreexpensivethantraditionalthermostat.b. DHPandresistanceheatingfoundmoreofteninlowerincomedwellings,whomaybelesswillingto

getamoreexpensivethermostat.c. DHPandzonalheatcustomersegmentinterestinWCTmaybelessthanotherresidentialHVAC

segments.d. Utilitypricingprogramsforcapacitydon’tyetexistinthePacificNorthwest.Theyarecoming.e. LackofawarenessbycustomersofWCTbenefits.f. ElectricHVACmarketusuallyinlowerincomemarket,whichmeansfocusonlowestpossibleinitial

cost,e.g.,ManufacturedhomeswithFAFcosting$250,orlowcostPTACsandwallheatersinapartments,etc.

g. Landlordtenantissues.h. LackofstandardsandcommunicationprotocolsinHVACcontrolsandWCTs.i. Setupandinstallationcostandchallenges.

3.3.2 Communication protocols being used and standards perspective.

CommunicationbetweenDHPandthermostatisproprietary.Therefore,usinga3rdpartyWCTmaybechallenging.SomeDHPvendorsareintegratingWCTswithDHPunits,butweareunsurewhatenergysavingvaluethismayhave.RegardingWCTsandhomemonitoringeachcompanysupportstheirownprotocol.Nestandpartners–Weave,HomeDepot–Wink,Lowes–Iris,Amazon–Echo,Apple–Homekit.


3.3.3 Themes for continued research, and field studies

InPNWresidentialsectors(SF,MH,MF),whataretheenergy/capacitysavingsandotherbenefitsfromusing:1)WCTswithDHPs,2)WCTswithDHPandsecondaryHVAC,and3)WCTswithElectricHVACandnoDHP?SeeRecommendationssectionforspecificstudies.

Ifsavingscanbeverified,thenconsider:

1. Participateorcontributetostudieslookingatcommunicationandprotocolstandards,e.g.,CEA

2045.Presently,EPRIandothersareinvolvedinCEA2045communicationwithwaterheaters,poolpumps,airconditioners,etc.ThismaynotbethebeststandardforWCTmarket,butisanexampleofprojectstopromotestandardenergyenduseequipmentcommunicationinterfaces.

2. MarketTransformationplanningwithWCTstoprovideenergyandcapacitysavingsinthePNW.OnceWCTsavingsareprovenandcosteffectivenessisexpectedtobeachievable,werecommendNEEAandpartnersconsideramarkettransformationstudytoevaluate.

3. EvaluateconsumerbehaviorwithWCTandElectricHVAC(DHP,zonal,FAF).Lookatdistinctionbetweentotalsavingsobservedandsavingsinbillinganalysis.

InEcotope’sstudiestheyfoundapproximately20%lossinenergysavingsbetweenthenetsavingsobservedfromthebillinganalysisandthetotalsavingsobservedfromtheoperationoftheDHP.Itislikelythattheconditionsthatwarrantthisincreaseinsavingsalsoexistinthelargerpilotpopulation,andasimilaradjustmentcouldbeapplied.Overall,itwouldappearthatmoredetailedunderstandingofthedistinctionbetweenthetotalsavingsobservedinthemeteringstudyandthesavingsderivedfromthebillinganalysisshouldbemoreclearlyunderstood.

4. EvaluatingbuildingcodesandmarkettoprovidelockoutofsecondaryHVAC.Usethermostat

stagecontrolswithERHVACequipment.

3.4 NEEA stakeholders are interested in WCT and Building Energy Management.

IntheNorthwest,BPA,publicpower,ETOandmetroutilities(multifamily)areperhapsthestakeholderthatwouldbenefitthemostfromfurtherresearchandprogressingettingWCTstoworkwithelectricspaceheating.InJanuary,MikeLublinerspenttimewithJanicePeterson,fromBPA’senergyefficiencygroup,atAHRIandASHRAEtalkingwithvendorsandconsideringtheopportunitiesforcommunicatingcontrolsforDHPandelectricresistanceHVAC.IOUsandETOhavepilotedprojectsusingNestandotherWCTs.Resultsareshowingpositivesigns,andBPATechnologyInnovationroadmapidentifiescontrolofsecondaryelectricheatasinconjunctionwiththeinstallationandoperationofDHPmini-splits.


BPATIRoadmapControlofelectricresistancezonalheatersinconjunctionwithductlessmini-splitheatpumps.Withtheinstallationofductlessheatpumps(DHPs)inhomeswithzonalelectricheatthereisnocontroloftheinteractionofthetwosystems.Occupantsdonotgetclearsignalswhentheelectricresistancesystemisoperatingwhenitisnotneeded(i.e.whenDHPiscoolingonorwhenDHPcouldhandletheloadifnotbeingoutpoweredbyelectricresistance).Keyresearchquestions:

1. Aretherecommercialavailablecontrollersofelectricresistanceheatersthatcancommunicatewithothercontrols?

2. Aretherecommercialavailablecontrollerstheclearlyindicatewhentheyareonandhavetoturntheelectricresistanceheatoffatthecontroller?

3. WhatistheenergysavingspenaltywhenelectricresistanceandDHPsystemcompete?4. Whatcontrolstrategiesproducethemostenergysaving?5. Whatistechnicallypossible?

NortheastandCanadaOutsidetheNorthwest,thereareothermarketswithhighpercentagesofelectriczonalandFAFHVACequipment,suchasCanadaandNortheast.Someofthevendorswe’vediscussedinthispaperarelocatedandsellingintothesemarkets.NEEAcouldconnectwithsimilarorganizationsIthesemarketstoevaluatethetechnologiesandmanufacturersdiscussedinthispaper,e.g.,NEEP10.27%ofCanadianhouseholdsareelectricallyheatedandhavestandardsandcoderelatedtoLineVoltageThermostats(LVT)11.Severalprovincesusecommunicatingthermostatsanduseitforcapacityfocusedprograms.

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