HIGH TEMPERATURE HEAT PUMPS for the Australian food industry · exhaust stream as well as ... High temperature heat pumps for the Australian food industry - Opportunities assessment

HIGH TEMPERATURE HEAT PUMPS for the Australian food industry: Opportunities assessment August 2017

AustralianAllianceforEnergyProductivity(A2EP) ii

AUTHORSHIPOFTHISREPORT

ThisreportispublishedbytheAustralianAllianceforEnergyProductivity(A2EP).A2EPisanindependent,not-forprofitcoalitionofbusiness,governmentandenvironmentalleaderspromotingamoreenergyproductiveandlesscarbonintensiveeconomy.

ThemembersoftheprojectteamthatcompiledthisreportareJonathanJutsen(A2EP),AlanPears(SeniorConsultant),LizHutton(ProjectManagerandResearcher).

©AustralianAllianceforEnergyProductivity2017

ThispublicationislicensedundertheCreativeCommonsAttribution4.0International(CCBY4.0),subjecttotheexemptionscontainedinthelicence.ThelegalcodeforthelicenceisavailableatCreativeCommons.

ACKNOWLEDGEMENTS

A2EPwouldliketothanktheNSWOfficeofEnvironmentandHeritagewithSustainabilityVictoriaandRMITUniversityforsupportingthiswork.

A2EPwouldalsoliketothankthemanystakeholderswhogenerouslygavetheirtimetoprovidevaluableinputandinsightsinthepreparationofthisreport.AfulllistofcontributorstothisreportcanbefoundinAppendixA:Heatpumpstakeholdercontributors.

Note:Acknowledgementofthissupportdoesnotindicatestakeholders’endorsementoftheviewsexpressedinthisreport.

Thewebsitewww.industrialheatpumps.nl,publishedbyDeKleijnEnergyConsultants&EngineersofTheNetherlands,isasourceoftechnicalinformationanddiagramscontainedinthisreport,andalsothefrontcoverimages.A2EPgratefullyacknowledgesthecontributionoftheworkofDeKleijnEnergyConsultantsandEngineers.

Whilereasonableeffortshavebeenmadetoensurethatthecontentsofthispublicationarefactuallycorrect,A2EP,SustainabilityVictoria,NSWOfficeofEnvironmentandHeritage,RMITUniversityandothercontributingstakeholdersgivenowarrantyregardingitsaccuracy,completeness,currencyorsuitabilityforanyparticularpurposeandtotheextentpermittedbylaw,donotacceptanyliabilityforlossordamagesincurredasaresultofrelianceplaceduponthecontentofthispublication.Thispublicationisprovidedonthebasisthatallpersonsaccessingitundertakeresponsibilityforassessingtherelevanceandaccuracyofitscontent.

Citation:Jutsen,J.,Pears,A.,Hutton,L.(2017).HightemperatureheatpumpsfortheAustralianforindustry:Opportunitiesassessment.Sydney:AustralianAllianceforEnergyProductivity.

AustralianAllianceforEnergyProductivity2017Level11,UTSBuilding10,235JonesStreet,Ultimo,NSW2007andRMIT,PCPM,L8,Building8,360SwanstonStreet,MelbourneVIC3000

email:[email protected]:0295144948web:www.a2ep.org.au,www.2xep.org.auABN:39137603993

AustralianAllianceforEnergyProductivity(A2EP) iii

ExecutiveSummaryThepurposeofthisreportwastodefinethelikelyfeasibility,andrangeofapplicationsforheatpumpsinthefoodindustry,withafocusonhightemperature(HT)heatpumpsdeliveringusefulheatat66oC-150oC.

Thisworkisacontinuationofthe2xEPprojectinvestigatingtheopportunitiesforinnovationintechnology/businessmodelsthatcouldtransformenergyproductivityinthefoodvaluechain(http://www.2xep.org.au/innovation-next-wave.html).Thefirstoverviewreportdefinedonekeytransformativechangeasbeingtheelectrificationoffoodprocessing,displacingfossil-fuelfiredboilersandsteamsystems.Onecentraltechnologyrequiredforthistransitionistheapplicationofheatpumpstorecoverheatfromwastestreamstoboosttemperatures,displacesteam,andinsomecasessimultaneouslyprovideprocesscooling.

ThisworkisparticularlyimportantatatimewhenEastCoastAustraliancompanieshaveseenasignificantriseingaspricesinthelasttwoyears,withpricesoftenmorethandoubling.Asheatpumpseffectivelyuseelectricitytoharnessheatfromwasteheatstreamsortheenvironmentatefficienciesofover300%,theycancosteffectivelydisplacegaswhengaspricesarehigh(andwhenthecostofrenewableelectricityisfallingrapidly–assolarPVcanbeusedtopowerheatpumps).

TheprojectteamconsultedextensivelywithstakeholdersandconductedresearchtodefineinternationalbestpracticesinheatpumpstechnologyandapplicationgloballyandtounderstandtheexperienceandcapacityinAustralia.Wethenevaluatedthelikelyeconomicreturnfromusingheatpumpsinarangeofapplicationslocally.Thisevaluationisatpre-feasibilitylevel.Basedonasuccessfuloutcomeofthisproject,wecouldpotentiallypilotheatpumpsinthemostpromisingapplicationswithstrongreplicationpotential.

Thekeyfindingsofthisprojectare:

Hightemperatureindustrialheatpumptechnologyhasdevelopedrapidlyinthepastdecade.Therearenowmanycommercialproductsforindustrialprocesses,includingthefoodprocessingindustry.Thousandsofunitsarenowinservice,inJapan,SouthKoreaand(toalesserextent)Europetosupplyheatatupto95oC.Andthetechnologyhasalsoextendedtodevelopmentofheatpumpsdeliveringsteamatupto150oC.Atthesametime,therearebarelyahandfulofhightemperature(over65oC)industrialinstallationsinAustralia.

HightemperatureheatpumpscouldplayanimportantroleinAustralianindustrytorecoverheatanddisplacesteam/hotwatergeneratedfromnaturalgas(andLPG).Withtherapidescalationingaspricesandpotentialgassupplyconstraints,andtheneedtomovetolowcarbonenergysolutions,hightemperatureheatpumptechnologycouldplayanimportantroleinAustralianindustry.

Themosteconomicallyattractiveapplicationsoccurwhereheatpumpscanbeusedtoupgradeheatfromwastestreamsand/orcapturelatentheat,(likewastewater,hothumidair(e.g.fromdryers),condenserheatfromrefrigerationsystems),andwheresimultaneousheatingandcoolingdutiescanbedelivered.Classicapplicationsofhightemperatureheatpumpsinfoodprocessinginclude:

• Fooddryingandwashingprocesses,wheretheheatpumpcoolsidecaptureslatentheatinthe

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exhauststreamaswellassensibleheattoprovidehot,dryinletair,waterorsteamattherequiredtemperature;

• Heatingprocessorcleaningwaterbyupgradingwasteheatfromawasteheatstreamorarefrigerationsystem;and,

• Pasteurisationwheretheheatpumpmayprovideheatingandcoolingdutiestodisplacesteam.

Theeconomicsofhightemperatureheatpumpshaveimprovedduetogaspriceescalation,technologydevelopmentandearlystageeconomiesofscale,andnowappearbroadlyviable.While,thereisasignificantcapitalcostforhightemperatureheatpumps,thedevelopmentofpackaged‘Ecocute’unitsinJapanprovidesrelativelyeconomicalvolumemanufacturedunitsforheatingwaterandairto90oC.Economicanalysisshouldconsiderallthevaluestreams.Manyinternationalcasestudiesonlyreportthedirectenergybenefits.ThevaluederivedfromusingHTheatpumpsmayincludefourtypesofenergyproductivitybenefits:

• DirectenergysavingsfromtheCOPofheatpumpsof3ormore(andwheresimultaneousheatingandcoolingispossible,thiscandouble).Ageneralisedcomparisonofthecostofgeneratingheatwithheatpumpsindicatesthatheatpumpsmaygenerateheatwithupto50oC+temperatureliftatsay$10/GJ(basedon$160/MWhpower);significantlylowerthanatypicalboilerandsteamsystemusingnaturalgas–at$12/GJgascost,heatdeliveredtoprocesswouldtypicallycostover$15/GJfromasteamsystem(>$25/GJforaninefficientsystem).

• Therecoveryofsensibleandinsomecasesalsolatentheat,whichwouldotherwisebewasted.• Useofheatpumpsassteppingstonestowardscompletereplacementofboilersandsteam

systems,generatingpotentiallymuchgreatersavings,whereexistingsystemshavelowefficiency.

• Additionalenergyproductivitybenefitsincludingenablingincreasedplantthroughput,betterheatingcontrolleadingtoproductqualityimprovementsandgreaterreliabilitythansteamsystems.

WhiletheeconomicsofHTheatpumpsareapplicationandsitespecific,itappearsthattherewillbemanyheatpumpsolutionsthatpaybackwithinsixyears(deliveringover15%perannuminternalrateofreturn)justbasedondirectenergybenefits.Wheretheseinstallationsallowretirementofboilersandsteamsystems,orwheretheheatpumpfulfilsacoolingandheatingdutysimultaneouslythesystemscouldpaybackinlessthan3years.Giventheseratesofreturn,thereispotentialforwell-designedfinancingmechanismstoprovidelowupfrontcost,cashflow-positivefinancepackagesforheatpumps.

TherearesignificantbarrierstoimplementationofHTheatpumpswhichexplainstheverysmallnumberofinstallationstodate.SomebarrierstoimplementingHTheatpumpsintheAustralianfoodindustryinclude:

• Historicallycheapcoalandthengasprices,whichhavesupportedthecontinuationofcentral,steambasedheatsupplysystemsandunder-investmentinenduseefficiencyimprovement;

• Lackofbusinessknowledgeoftheapplicationofthistechnologyastherearealmostnolocalexamplesandlimitedlocalsupplierexpertise;

• Limitedincentivestoimplementthetechnology(whichwerecentraltorapiddeploymentinJapanandKorea);

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• ThereisskillrequiredtooptimallyimplementHTheatpumps(otherthaninapplicationsthatjustdirectlyreplaceaheatingsource)includingusing‘pinch’thermodynamicanalysis,anddetermininghowtoextractthegreatesttotalbusinessbenefit.ThisexpertiseisnotwidespreadintheAustralianmarket.

ThesebarriershavebeenovercomeinJapanandKoreathroughgovernmentsupportincludinginformationprovision,technicalsupportincentives,andinvestmentincentives.

TheprojectteambelievesthatthereissufficientpotentialforapplicationofHTheatpumpstodisplacenaturalgasanddeliveranattractivereturnfortheAustralianfoodindustrythatfurtherworkisjustifiedtodevelopthemarket.Thismayincludepart-fundingtheconductofdetailedfeasibilitystudiesandcaseimplementationprojects,todemonstratetheapplicationinapplicationswherethereissubstantialreplicationpotential.

AlistofrecommendedactionsisprovidedSection8Conclusionsandnextsteps.

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Contents1 Purposeandcontextofthisreport................................................................................1

2 Scopeofworkandprocessfordevelopingthereport....................................................2

3 Hightemperatureheatpumptechnologyandoverviewofapplications........................33.1 Technologyoverview....................................................................................................................33.1.1 Basics......................................................................................................................................33.1.2 Efficiency-Coefficientofperformance...................................................................................53.1.3 Refrigerants............................................................................................................................53.1.4 Developmentsinheatpumptechnology................................................................................63.1.5 Examplesofnewtechnologyapplications..............................................................................7

4 HeatpumpapplicationsforAustralianfoodprocessing...............................................114.1 Dryingprocesses.........................................................................................................................134.2 Washingprocesses......................................................................................................................144.3 Heatingprocesswaterusinganaddonheatpumptoarefrigerationsystem...........................154.4 Pasteurisation..............................................................................................................................18

5 Commercialfeasibilityfactorsandbarrierstoimplementation...................................205.1 Commercialfeasibilityfactors.....................................................................................................205.2 Barrierstoimplementation.........................................................................................................32

6 Industrialapplicationsandcasestudyexamples.........................................................346.1 Sampleinternationalindustrialapplications...............................................................................346.1.1 HeatpumponaFrenchfrydryer..........................................................................................346.1.2 Add-onheatpumpinthefoodindustry................................................................................346.1.3 Hybridheatpumpatslaughterhouse...................................................................................346.1.4 Add-onheatpumpforsportscentre.....................................................................................356.1.5 Canadiandairyplant1..........................................................................................................356.1.6 Canadiandairyplant2..........................................................................................................366.1.7 Poultryprocessingandmeatpackingplants........................................................................366.1.8 Babyfoodprocessingplant...................................................................................................37

6.2 Australiancasestudies................................................................................................................386.2.1 LobethalAbattoir,SouthAustralia.......................................................................................406.2.2 SheneEstateDistillery,Tasmania.........................................................................................426.2.3 Foodprocessingfacility,Victoria..........................................................................................436.2.4 Saltprocessingfacility,Victoria............................................................................................44

7 Scaleofopportunity....................................................................................................45

8 Conclusionsandnextsteps.........................................................................................48

AppendixA:Heatpumpstakeholdercontributors............................................................50

AppendixB:Internationaltechnologyreview...................................................................51B.1Foodindustrycasestudies............................................................................................................51B.2Researchanddevelopment..........................................................................................................54

AppendixC:CoefficientofperformancebackgroundInformation.....................................57

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AppendixD:Hightemperatureheatpumpswithnaturalrefrigerants...............................58

AppendixE:Pinchanalysis................................................................................................62

Figures

Figure1–Heatpumpleverage:Mostinputfromlowergradeheatstreamsorrenewablesources....3

Figure2–Heatpumpcomponents.......................................................................................................3

Figure3–Thethermodynamiccycle(usingammonia).........................................................................4

Figure4–Refrigerantcharacteristics:temperatureversuspressure...................................................5

Figure5–Characteristicsofaselectionofrefrigerants........................................................................6

Figure6–Heatpumpdevelopments....................................................................................................7

Figure7–CO2heatpumpsforheatingwaterandair(Mayekawa)......................................................8

Figure8–TypicalapplicationofreverseRankineheatpump...............................................................9

Figure9–Cascadedormulti-stageheatpumps(KOBELCO:SGHseries)..............................................9

Figure10–Steamgenerationpump:amixtureofHFC245faandHFC134arefrigerant(KobeSteel) 10

Figure11–Energycontentofairandwatervapourinsaturatedair(kJ/kgofdryair)........................12

Figure12–Conventionaldryingprocess.............................................................................................13

Figure13–Industrialwashingmachinewithheatpump....................................................................14

Figure14–Add-onheatpump............................................................................................................16

Figure15–Refrigerationsystem.........................................................................................................17

Figure16–Conventionalpasteurizationprocess................................................................................18

Figure17–Pasteurizationprocesswithadd-onheatpump................................................................19

Figure18–TransitionfromIndustry1.0toIndustry4.0.....................................................................22

Figure19–RelativecostofelectricitytogasinEuropeancountries..................................................23

Figure20–Heatpumptemperatureliftversuscostofdeliveredheat..............................................24

Figure21–Infrastructureinafactoryusingdistributedheatpumps.................................................28

Figure22–Heatpumpwithoutthermalstoragetank.........................................................................29

Figure23–Heatpumpwiththermalstoragetank..............................................................................29

Figure24–CO2trans-criticalindustrialheatpumpinCanadiandairyplant.......................................35

Figure25–NH3heatrecoveryheatpumpinaCanadiandairyplant..................................................36

Figure26–Combinedcooling/heatingusingheatpumpsintwoexampleapplications....................36

Figure27–Energy/watersavingsatbabyfoodplant.........................................................................37

Figure28–Coefficientofperformanceforheatingforammoniarefrigerant....................................57

HightemperatureheatpumpsfortheAustralianfoodindustry-Opportunitiesassessment

AustralianAllianceforEnergyProductivity(A2EP) 1

1 Purposeandcontextofthisreport

ThisreportwaspreparedbytheAustralianAllianceforEnergyProductivity(A2EP).A2EPisanindependent,not-forprofitcoalitionpromotingdoublingtheenergyproductivityoftheeconomyby2030.

Thisreportexaminesthefeasibilityofutilisingindustrialheatpumpsproducingoutputfluidsat66oC-150oCforfoodprocessing.

Thisworkisacontinuationofthe2xEPprojectinvestigatingtheopportunitiesforinnovationintechnology/businessmodelsthatcouldtransformenergyproductivityinthefoodvaluechainfromplatebacktofarm.Thisprojectfollowsfromourfindingthatonekeytransformativechangewouldbetheelectrificationoffoodprocessing,displacingfossilfuelfiredthermalprocesses.Onekeyelementofthischangewasseentobetheapplicationofdistributedheatpumpstorecoverheat,displaceboilersandsteamsystemsandinsomecasessimultaneouslyprovideprocesscooling.

ThisworkisparticularlyimportantatatimewhenEastCoastAustraliancompanieshaveseenarapidescalationofgaspricesinthelasttwoyears,withmanycompaniesseeingcontractpricesdoublefrom$6/GJto$12/GJormore.Inaddition,renewableelectricitycostshavefallenandthereisanincreasingfocusondemand-sideenergyproductivityimprovement.Increasingnumbersofbusinessesareinvestingin‘behindthemeter’renewablesandimprovementsinprocessefficiency,whilebeginningtorecognisethemanybusinessbenefitsofinnovation.Asheatpumpseffectivelyuseelectricitytoharnessheatfromwasteheatstreamsortheenvironment,theycanverycosteffectivelydisplacegaswhendomesticpricesasthesefactorsplayout.

Ouraimsfromthisworkwereto:

• Understandtheavailabilityofheatpumptechnology;

• DeterminewhetherheatpumpsarelikelytobeeconomicalinAustralianfoodprocessingapplications;

• Definebarrierstobeovercometoallowincreasedapplication;andfinally,

• Definethenextstepsthatshouldbetakentofulfilthepotentialofthistechnologyinthelocalmarket.

Whatisenergyproductivity?

Energyproductivity(EP)referstothevaluecreatedfromusingaunitofenergy.ToimproveEP,wecanincreaseeconomicvalueaddedbyusingenergymoreeffectively,oruselessenergy–inshort,domorewiththeenergyweuse.

EP=Valueadded($)/Energy(primary,GJ)

Theidealcommerciallysustainableapplicationsforheatpumpsinindustrywillhavebothproductivityaswellasenergybenefits,forexample,improvedplantreliability,reducedmaintenance,enhancedcontrollability,improvedproductqualityorincreasedthroughput.Thiscouldbedirectlythroughapplicationofthetechnologyorthroughenablingthepartialorcompletereplacementofcentralsteamandhotwatersystemswithhighlyautomatedlocalheatingsystemsusingheatpumpsandotherhighlyproductiveelectro-technologies.Boilersandsteamsystemsoftenhavesurprisinglypoorsystemefficiencies,andhighmaintenanceburden.



2 Scopeofworkandprocessfordevelopingthereport

Thisreportwaspreparedusingtheapproachsetoutbelow.

Scopeofworkandmethodology

1. ExamineinternationalbestpracticeandworkdonetodateinAustraliaonhightemperature(HT)heatpumpsthroughwebresearchanddirectcontacts.

2. DevelopastakeholdergroupofpartiesinterestedinHTheatpumptechnologyapplicationsincludingequipmentsuppliers,researchers,potentialend-users,andgovernment.Wealsoinvitedour65-person2xEPInnovationworkinggrouptoprovideinput.Weinterviewedarangeofkeystakeholderstounderstandthecurrentmarketandsomeofthekeytechnologyoptionsandbarriers(seeAppendixA:Heatpumpstakeholdercontributors).

3. DefineidealapplicationsofindustrialheatpumpsinAustralianfoodprocessing,takingintoaccountAustralianconditionssuchas:thesmallscaleofthemarketandthefactthatmostcompaniesmakeavarietyofproductsinshortproductruns;thecompetitivesituation,profitabilityandinvestmentplansoflocalbusinesses;energypricesandtrends–andtheimpactofrapidlyescalatinggasandgridelectricityprices,fallingon-sitegovernmentenergyandcarbonpolicies,decliningcostsofrenewableelectricity,climaticconditions(andrangeofconditionsinNSWandVictoriabyseason);and,otherfactorsidentifiedinthecourseofthework.

4. Selectthemostpromisingapplicationsandconductpre-feasibilityanalysesincludingfirstcutcostsandbenefits.Itproveddifficultwithinthetimeperiodtodevelopreallifecaseexamples,andtherearesofewinthemarketthiswaschallengingandwehadtotrytogetcaseexamplesfromlinkingcompanieswithsites.

5. Extrapolatethefindingsfrom3.and4.todefinethelargerscaleopportunitiesandchallengesforHTheatpumpsinthefoodprocessingindustry.Definepotentialgasdisplacementpotentialandgreenhousegassavingspotential.

Deliverables

1. Draftreportcoveringthedefinedscope,distributedtostakeholdersforcomment.

2. Workshopconductedbyphone,invitingthekeystakeholderstodiscussthedraft.

3. Finalreport,deliveredtofundersandstakeholdersandpostedontheA2EPwebsite.

4. Fourfactsheets-onepagecasesummariesof3Australiancasestudiesanda1pageoverviewfactsheetonhightemperatureheatpumpsforthefoodindustry.



3 Hightemperatureheatpumptechnologyandoverviewofapplications

3.1 Technologyoverview

3.1.1 Basics

Industrialheatpumpsusearefrigerationcycletoveryefficientlytransferheatfromtheenvironmenttowasteheatstreams.Heatpumptechnology(drivenbyelectricity)candisplacegasandupgradeheat(bothsensibleandlatent)fromwastestreamssuchaswastewater,hothumidair(e.g.fromdryers)andcondenserheatfromrefrigerationsystems,forutilisationinarangeofapplicationslikeblanchers,dryersandpasteurisers,asdepictedinFigure1and2below.

Figure1–Heatpumpleverage:Mostinputfromlowergradeheatstreamsorrenewablesources

Source:Pachai,AC2013,Applyingaheatpumptoanindustrialcascadesystem

Figure2–Heatpumpcomponents

Source:DeKleijn2017,www.industrialheatpumps.nl

PreferablyfromPV

à



Heatpumpscanplayanumberofroles:

• Raisethetemperatureofafluid.

• Simultaneouslycoolafluid,whichcanalsobeusedfordehumidifying.

• Recoverwasteheatfromastream,includinglatentheatfromwatervapour.

Alowtemperaturewasteheatflowcanbeupgradedtousefulhightemperatureheatusingaheatpump.Themechanicalheatpumpdrivenbyanelectricmotoristhemostwidelyused.Itsoperatingprincipleisbasedoncompressionandexpansionofarefrigerant.Aheatpumphasfourmaincomponents:evaporator,compressor,condenserandexpansiondevice.Intheevaporator,heatisextractedfromawasteheatsourcebyevaporatingtherefrigerantatlowpressure.Thegasiscompressedanditstemperatureincreases(justlikeinabicyclepump).Inthecondenser,thisheatisdeliveredtotheprocessatahighertemperatureastherefrigerantcondensesandreleasesitslatentheat.Electricenergydrivesthecompressorandthisenergyisaddedtotheheatthatisavailableinthecondenser.Theefficiencyoftheheatpumpisdenotedbyits‘coefficientofperformance’(COP),whereaCOPof3meansthreetimesasmuchheatenergyisdeliveredastheamountofmechanicalworkinputfromthecompressor.

Figure3–Thethermodynamiccycle(usingammonia)


Inthefigureabove,theblacklineshowstherelationshipbetweenpressureandboilingpointofAmmonia.AtlowpressureandtemperatureAmmoniaisevaporatedintheevaporator,absorbingheatastheliquidisconvertedintogas–storingthelatentheatofvaporisation.Theenergyneededforthisisprovidedbyawaste-heatstream.ThecompressorincreasesthepressureoftheAmmoniavapour,increasingitstemperature(likeinabikepump).Thevapouristhencondensedathighpressureandtemperatureinsidethecondenser,releasingitslatentheatofvaporisation.DuringthecondensationofAmmonia,heatisreleasedatahighertemperature:ausefulsourceofenergy.TheliquidAmmoniaistransportedtotheexpansiondevicethatlowerspressure.Thelowtemperature,lowpressureAmmoniaflowstotheevaporatorwhereitagainabsorbsheatenergyasitevaporates.



3.1.2 Efficiency-Coefficientofperformance

Theefficiencyofrefrigerationsystemsandheatpumpsisdenotedbythecoefficientofperformance(COP).TheCOPistheratiobetweenenergyusageofthecompressorandtheamountofusefulcoolingattheevaporator(forarefrigerationinstallation)orusefulheatextractedfromthecondenser(foraheatpump).Mostoftheelectricenergyneededtodrivethecompressorisreleasedtotherefrigerantasheat,somoreheatisavailableatthecondenserthanisextractedattheevaporatoroftheheatpump.ForaheatpumpaCOPvalueof4meansthattheadditionof1kWofelectricenergyisusedtoachieveareleaseof4kWofheatatthecondenser.Attheevaporatorside3.0-3.5kWofheatisextractedandadditionalheatfromtheelectricityinputtorunthemotor/compressorisadded,sothatatotalof4unitsofheatisdeliveredwhenonly1unitofelectricity(ormechanicalenergy)isused.

FormoreinformationonCOPseeAppendixC:CoefficientofperformancebackgroundInformation.

3.1.3 Refrigerants

Avarietyofrefrigerantsareavailableforusageinmechanicalheatpumps.Improvedrefrigerantsarebeingdevelopedovertime.Evenwatercanactasarefrigerantifthepressuresandtemperaturesaremanagedappropriately:infact,becauseithasaveryhighlatentheatofevaporationitcanbeveryeffective.Dependingontheircharacteristics,differentrefrigerantsaresuitablefordifferenttemperatureranges,andhavedifferentefficiencies.Selectionisbasedonseveralcriteria:

Pressure:Atagiventemperaturethecondensationpressureisdifferentfordifferentrefrigerants.

Figure4–Refrigerantcharacteristics:temperatureversuspressure


Criticaltemperature:Aboveacertaintemperaturearefrigerantreachesitssupercriticalarea.Withinthesupercriticalrangethefluidandgaseousphaseoftherefrigerantcannolongerbedistinguished.



Energyefficiency:Theefficiencyofaheatpumpdependsonthechoiceofrefrigerant.

Naturalversussyntheticrefrigerants:Mostsyntheticrefrigerants(mostlyHFCs,asCFCs,whichalsodamagedtheozonelayer,havebeenphasedout)contributestronglytothegreenhouseeffect.Thisimpactcanbe3,000timeshigherthanCO2.Naturalrefrigerantswithverylowclimateimpactareavailable,andthesemayworkmoreefficientlythantherefrigerantstheyreplace.Syntheticrefrigerantswithlowerclimateimpactsarealsobeingdeveloped.Sincedifferentrefrigerantshavedifferingheattransfercapacityandlatentheat,changingrefrigerantsmayaffecttheoverallheatingorcoolingcapacityofasystem.Thismayleadtoaneedtoreplaceequipment,ortoimplementenergysavingmeasuresthatreducetheamountofheatingorcoolingrequired.

Otherselectionfactorsincludeinvestmentcosts,requiredsizeoftheinstallationandsafetyandpermits.FormoreinformationonnaturalrefrigerantsseeAppendix D: High temperature heat pumps with natural refrigerants.

Figure5–Characteristicsofaselectionofrefrigerants


3.1.4 Developmentsinheatpumptechnology

Heatpumptechnologyhasrapidlydevelopedinthelastdecade,particularlyHTheatpumpstodelivertemperaturesofover80°C(andupto140-150C°forcascadedormulti-stageheatpumps).Becauseheatpumpsaremoreefficientwhenoperatingacrossasmallertemperaturedifference(about2-4percentperdegreereduction),systemsthatusemultipleheatpumpsinseries(cascadingormulti-stage)canachievelargeefficiencyimprovements,sotheycanoperateacrosslargeroveralltemperaturedifferencesathighefficiencies,althoughtheyaremorecomplexandexpensive.Thesedevelopmentshavegreatlyextendedtherangeofapplications.HTindustrialheatpumptechnologydevelopmentinJapanhasfocusedon:

• Hotwaterandhotairsupply,usingCO2refrigerant.Thesepackaged‘Eco-Cute’heatpumpscanproducehotwateratupto90°Cwithaheatingcapacityofupto72kW,and



havebeencommercializedinJapanandsoldglobally.• CO2heatpumps,capableofgeneratinghotairto100°Cwithaheatingcapacityof110kW,

havebeenalsocommercializedinJapan.• Heatingandcoolingofcirculatingwaterandsteamgenerationusing‘ReverseRankine’

cycle.• TheJapanesehavealsoreportedondevelopmentofindustrialheatpumpsthatcan

providesteamat120to165°Cusingcascadingormulti-stageapproaches.

Improvingtechnologiesandeconomiesofscaleofproductionofpackagedunitsaremakingheatpumpsmorecompetitive,supportedbydecliningcostsofrenewableelectricity(andenergystorage)andincreasingcostsofnaturalgas.

Someexamplesoftheuseofthesetechnologiesareprovidedonthefollowingpages.

Figure6–Heatpumpdevelopments

Source:IEAHPPAnnex352013,ApplicationofIndustrialHeatPumps,Task3

3.1.5 Examplesofnewtechnologyapplications

PackagedCO2heatpumps

Figure7(left)showsatypicalarrangementandenergyflowsofaCO2refrigerantair-sourceheatpump(withreciprocatingscrewcompressor)supplyinghotwater,deliveringhotwateratatemperatureof90°C,andwithaheatingcapacityof74kWandCOPof4.2.Figure7(right)showsthe



typicalarrangementandenergyflowsofaCO2refrigerantwatersourceheatpumpwhenusedforthesupplyofhotair,whichcangeneratehotairatatemperatureof100°C,withaheatingcapacityof110kWandCOP3.7.

Figure7–CO2heatpumpsforheatingwaterandair(Mayekawa)

Source:IEAHPTAnnex352014,ApplicationofIndustrialHeatPumps,PioneeringIndustrialHeatpumpTechnologyinJapan

Heatingcirculatinghotwater

Inmanyindustrialprocesses,hotwaterafterbeingcooledby5to10°Cisreheatedandcirculated.The reverseRankine cycle iswell suitedused for heating circulatinghotwater at 60 to80°C, anddeliversahighCOP.

Figure8showsaschematicofatypicalapplicationofthereverseRankinecycleair-orwater-sourceheatpumpwithHFC-134arefrigerant.Whilecoolingwater-solublecuttingoil,thisheatpumpheatsthe liquid, which washes the machined parts, thus providing simultaneous cooling and heating.Threeoperatingmodes-heatingmode,coolingmodeandheatingandcoolingmode-areavailable,using the heat exchanger between the air and refrigerant in either direction of heat flow, asrequired.ThetotalCOPinheatingandcoolingmodereaches5.

Asanexampleoftheeffectachievedusingtheseheatpumps,areductionof84%inprimaryenergyconsumptionand80%inCO2emissionscomparedwiththeconventionalcombinationofcoolingbychiller and heating by boiler steam, has been reported. At factories producing cars or auto parts,manyheatpumpsofthistypearestartingtobeadopted.



Figure8–TypicalapplicationofreverseRankineheatpump

Source:IEAHPTAnnex352014,ApplicationofIndustrialHeatPumps,PioneeringIndustrialHeatpumpTechnologyinJapan

Cascading/multi-stageheatpumpsforsteamgeneration

Cascadedormulti-stageheatpumpsandotheroptionstoachievelargertemperatureincreaseswhilemaintainingefficiencyarebeingdevelopedinJapan(see9).Byusingheatpumpsinseries,thetemperaturedifferenceacrosseachunitisreduced:efficiencyimprovesby2-4%foreachdegreereductioninthetemperaturedifference,solargeefficiencygainscanbeachieved,althoughequipmentcostisincreased.Alternatively,largertemperatureincreasescanbeachievedatsimilarefficiency.

Figure9–Cascadedormulti-stageheatpumps(KOBELCO:SGHseries)




Exampleofsteamgenerationusingheatpumps

SinceanHFC-245farefrigeranthasacriticaltemperatureexceeding150°C,asingle-stagecompressionortwo-stagecompressionheatpumpcanbeusedforre-heatingcirculatinghotwateratatemperatureexceeding80°C,orsteamgenerationatatemperatureexceeding100°C.Thedualcycle,whichconsistsofanHFC-245facycleforthehigh-temperatureside,andanotherrefrigerant(HFC-134aorHFC-410A)forthelow-temperatureside,isalsoefficient.

Figure10showsaschematicdiagramoftwomodelsofasteam-generatingheatpump.TheSGH120versiongeneratessteaminitiallybyheatingpressurisedwaterandevaporatingitinaflashtankafterleavingtheheatpumpunit.Thismodelgeneratessteamat120°C,withaflowrateof0.51t/handaCOPof3.5fromawastehotwaterinputtemperatureof65°C.

TheSGH165modelgeneratessteamat165°C.Aftertheheatpumpunitgeneratessteam,thesteamcompressorincreasesthesteampressureandtemperaturestillfurther.Theflowrateofthesteamis0.89t/handtheCOPreaches2.5fromawastehotwatertemperatureof70°C.TheSGH120modelhasasinglestagecompressorwithaflashtank,andtheSGH165modelhasaddsasteamcompressor.HFC-245faisselectedastherefrigerantoftheSGH120model,andamixtureofHFC-245faandHFC-134aisselectedastherefrigerantoftheSGH165model,consideringthecapacityperunitrefrigerantflow.

Figure10–Steamgenerationpump:amixtureofHFC245faandHFC134arefrigerant(KobeSteel)




4 HeatpumpapplicationsforAustralianfoodprocessing

Typicalheatpumpapplicationsaresummarisedinthetablebelow:

Applicationtype Features TypicalIndustries

DryersCapturesensibleandlatentheatfromexhauststreams Milk,pasta,noodles…

FoodwashingCapturesensibleandlatentheat(watervapour)fromexhauststreams

Potatoes,vegetables,fruit

Waterheatingforprocessandcleaning

Capturewasteheatfromprocessorrefrigeration(orair)compressors Allfood

Pasteurisation Canbeheatingand/orcoolingrole Milk,juices,…..

Combinedprocessheatingandcooling

Idealapplicationsusethecondenserforheatingandevaporatorforcoolingsimultaneously

Anexampleisbread-productcoolingandproving

Drying

Food dryers generally use air heatedwith steam, gas or hotwater.Warm air picks upmoisturefromthewetproduct,andgenerally thishumidwarmair isexhaustedandwasted.Conventionalheatexchangerscanonlycaptureaproportionof thiswasteheat.Aheatpumpcanextractheatfromthehumidair-bothsensibleheatandlatentheatbycondensingthewatervapour.Thenowdrycoolairisheatedbytheheatpumpforreuseinthedryer.(Notethatthelatentheataccountsformostoftheavailableenergyinthehumidwarmairstreams).

Thefigurebelowshowsthelatentandsensibleheatcontentofsaturatedair,andhowaheatpumpcanrecoverit.Asnotedelsewhere,theheatpumpcanalsoupgradethetemperatureoftheheatitrecovers.



Figure11–Energycontentofairandwatervapourinsaturatedair(kJ/kgofdryair)

Source:PearsA2017,IdentifyingHeatRecoveryOpportunities,PlantEnergyEfficiencyConference,22-23May,HiltonMelbourneSouthWharf

Heatingprocesswaterwithwasteheatfromarefrigerationsystem

Wasteheatfromarefrigerationsystemtypicallyhasatemperatureof25to30°C.Withtheuseofanadd-onheatpump,wasteheatfromthecondensingsideoftherefrigerationsystemisusedtoheatwatertotemperaturesupto80°C,atCOPsof4orhigher.

Pasteurization

Thepasteurisationprocessrequiresproductstobeheatedabove70°C,andthencooled.Heatexchange(regeneration)betweencoldandhotproductflowsisalreadyimplemented,butislimitedbyheatexchangerefficienciesandequipmentdesign.Extraheatingtobringtheproducttopasteurisationtemperatureistypicallyprovidedbysteam,andproductcoolingafterheatexchangeisprovidedbyexternallysourcedchilledwater.Aheatpumpcanextractheatfromtheproducttobecooled(displacingcoolingfromchilledwater)andsupplythisheatatahighertemperaturetoproducttoreachpasteurizationtemperature(displacingsteam).Thisisanexampleofaheatpumpsimultaneouslyheatingandcoolingaprocess.Inthesecases,theeffectiveCOPcanbeparticularlyhigh,butthisbenefitneedstobebalancedwithschedulingchallenges.

05001000150020002500300035004000

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90

enthalpykJ/kgdryair enthalpywatervapourkJ/kg

EnergyfromdehumidiIicationatconstanttemperature

kJ/kgofdryair

Temperature(degreesC)

Energyfromtempreductionbyheatexchanger



Waterheatingforprocessandplantcleaning(includingcleaninginplace–CIPsystems)

Waterisneededatelevatedtemperatures–typically65°C+forcleaningprocessplant,includingusingcleaninginplace(CIPsystems),aswellasforprocessneedsattemperaturesupto80°C+.Heatpumpsarewellsuitedtothisduty.TheJapanese‘EcoCute’heatpumpsthatuseCO2asrefrigerantarewellsuitedtoprovidingheatatthesetemperatureswithahighCOP.

4.1 Dryingprocesses

Themostcommondryertypeisoneinwhichairisheatedwithsteam,gasorhotwaterandthencirculatedoverthewetproduct.Astheairpicksupmoisturefromthewetproduct,itshumidityincreasesandtheenergycontainedinthewarmvapourstreammaymakeitausefulheatsource.Indeed,sinceevaporationconsumesover2.3MJ/litre,thereisusuallyalargeamountofpotentiallyusefulenergyavailablefromcondensingthewatervapour(seeFigure11whichshowstheenergycontentofsaturatedair).Normallythishumidairisexhausted.Withaheatpump,heatcanbeextractedfromthehumidair.Theairiscooleddownanddehumidifiedintheevaporator.Theextractedheatcanbeupgradedintemperaturebytheheatpumpandusedtoheatthedryer.So,theheatpumpservestwopurposes-heatthedryeranddehumidifyandrecirculateair,deliveringhighenergyefficiency.Thefigurebelowshowsatypicaltraditionaldryer.Hotair(1)at70°C,iscirculatedoveraproductbeltinsidethedryer.Thehotairisusedtoevaporatewaterfromtheproduct,andthetemperatureoftheairdecreasesanditshumidityincreases.Thecool,humidair(2)isthenpartlyexhausted,however,themainpartoftheairisrecirculatedinthedryer.Tocompensateforexhaustedhumidair,freshdryoutsideairisbroughtintothecycle(3)andpreheated(4).Afterpreheatingthisairismixedwiththerecirculatedhumidairandthemixture(5)isthenheatedtotherequiredprocesstemperature.

Figure12–Conventionaldryingprocess


Theexhaustedhumidaircontainsalotofenergy.Thetemperaturelevelofthisairislowanddirectreuseinsidethedryeristhereforenotpossible.Applicationofaheatpumpgivesthepossibilityforwasteheatrecovery.Withaheatpumptheextractedlatentheatfromtheexhaustairisupgradedtoahighertemperaturelevelandreusedtoheatthedryer.



Thisapproachisnowusedindomesticheatpumpclothesdryers,whichnowachieveenergysavingsof60to75%relativetotraditionalresistiveheatingdryers.Thesedryersdonotneedventing,althoughthecondensedwatermustberemovedorpumpedaway.

4.2 Washingprocesses

Washingoffoodnormallyinvolvessprayinghotwater,sometimesmixedwithasolvent,overtheproduct.Aconventionalwashingmachineisshowbelow.Thewashingwaterispumpedthroughaheatexchangerandisheatedbyagas-firedboiler.Thewashingwaterispressurizedwithasprayfanandsprayedovertheproduct.Somewashingwaterwillevaporateintheair,butmostflowsbacktothewatertank.Thewashinginstallationisoftenequippedwithanairdischargefantopreventtheinstallationfromvapourflowingoutthroughtheopeningsinthewashingmachine.Theairdischargeblowshumidhotairtotheatmosphereandmaintainsanegativepressureinsidethewashingmachine.Thedischargeaircontainsalargeamountofenergy.

Figure13–Industrialwashingmachinewithheatpump


Usingaheatpump,itispossibletoreusetheheatfromthedischargeairtoheatthewashingwater.Awashingmachinewithheatpumpisshownabove.Theevaporator(coldside)oftheheatpumpisplacedinsidetheairdischargeduct.Intheevaporator,humidairiscooleddownbelowthedewpoint.Thetemperaturelevelofthiswasteheatisincreasedbytheheatpump.Inthecondenser,thisheatisusedtoheatthecentralheatingcircuitofthewashingmachine.Itwillstillbenecessarytousesomesteam(orheatfromanotherexternalsource)toheatwashingmachinesoftraditionaldesign.Butahighlyinsulatedunitshould,inprinciple,notneedadditionalexternalheat,astheheatfromtheelectricityinputdrivingthemotorcouldoffsetmodestheatlosses.Itisalsopossibletodirectlyheatthewashingwaterwiththecondenser.However,whenawashingmachinehasmorethanonewashingsection,itiseasiertoheatthecentralheatingcircuit.



Toachieveahighefficiency,itisimportantthatthedischargeairhasahighrelativehumidity.Thiscanbeattainedbycontrollingtheamountofdischargeairbasedontherelativehumidityorthepressureinsidethewashingmachine.Thismeansthat,withoutaheatpumptocapturethatlatentheat,efficiencyislow.

Theheatdemandofthewashinginstallationdependson:

• In-outgoingtemperatureoftheproduct.

• Amountofvapourthatisevaporatedanddischarged.

• Heatlossesthroughsurfaceofwashingmachine.

Basedonthesizeofeachoftheseheatflows,itispossibletodetermineifthecompletewashingmachinecanbeheatedwithaheatpump.

4.3 Heatingprocesswaterusinganaddonheatpumptoarefrigerationsystem

Typically,thefoodindustryneedstocool/freezeproductsbeforetransport.Hotwaterisneededfortheprocessandforcleaningpurposes.Wasteheatfromarefrigerationsystemtypicallyhasatemperatureof25to30°C.Withtheuseofanadd-onheatpump,wasteheatfromthecondensingsideoftherefrigerationsystemisusedtoheatwatertotemperaturesupto80°C.Theadd-onheatpumpwillfurtherincreasethepressureoftherefrigerantfromtherefrigerationsystemtoachievehighcondensationtemperatures.



Figure14–Add-onheatpump


Thefigureaboveshowsanindustrialrefrigerationinstallationonwhichanadd-onheatpumpisinstalled.Twopipesconnecttheadd-onheatpumptotherefrigerationsystem.Thecompressoroftheadd-onheatpumpispositionedinserieswiththecompressoroftherefrigerationsystem.Theheatpumpcompressorwillfurtherincreasethepressureofthecompressedgasesfromtherefrigerationsystem.Acondensationtemperatureof70°Cresultsincleaningwaterof65-70°C.Thepressureofthecondensedrefrigerantattheoutletofthecondenserisreducedanditflowsbacktotherefrigerationsystem.

Thedischargegasesoftherefrigerationsystemcondensateatatemperatureof25to30°C,however,duetocompressiontheyaresuperheatedupto60to100°C.Thesuperheatedgasesarecooleddownbyanintercoolerbeforetheyarefurthercompressedbytheheatpump.Coolingoccursbymixingliquidrefrigerantfromthecondenserwiththesuperheatedgases.Becausethegasesarecooled,compressionwillbemuchmoreefficient.Moreover,dischargegastemperaturesoftheheatpumpcompressorarenottoohigh.Toohightemperaturesmaydemolishcompressoroil.

Thecapacityoftheheatpumpcompressoriscontrolledbytheheatdemandofthecleaningwaterflowingthroughthecondenser.Thecapacityandthustheamountofcompressedgasesflowingthroughtheheatpumpcompressorvariesduetothiscontrolsystem.Therefrigerationcondensertakescareofcondensationoftheremainingcompressedgases.Onlytherequiredheatisprocessedbytheadd-onheatpump.



Figure15–Refrigerationsystem


Thefigureaboveshowsatypicaltypeofrefrigerationinstallation.Theseparationvesselcontainsfluidaswellasgaseousrefrigerant.Thefluidrefrigerantiscirculatedoverevaporatorswiththeuseofapump.Therefrigeranttemperatureislowerthantheprocessthatneedstobecooled.Therefore,therefrigerantcanextractheatoutoftheprocessattheevaporator.Theheatcausestherefrigeranttopartiallyevaporate.Thegas/liquidmixtureisthenledtotheseparationvessel.Tomaintainaconstantpressurelevelinsidethevessel,gasisextractedfromtheseparatorbythecompressor.Duetothecompression,boththepressureandtheboilingpointoftherefrigerantareincreased.Duetothishigherboilingpointcompressedgasescanreleaseheattowardstheirenvironment.Thisheatreleasetakesplaceinsidethecondenseroftherefrigerationsystem.Becauseoftheheatthatisremovedtherefrigerantwillcondense(becomeliquid–[bothgasorliquidcanbecalledafluid]).Thepressureofthefluidrefrigerantisthenloweredanditistransportedbacktotheseparationvessel.Hence,yetanothercyclecanbestarted.

Theamountofwasteheatthatisreleasedatthecondensersideisalmostequaltotheheatthatisextractedfromtheproductthatneedstobecooled.Thedifferenceisadditionalenergyduetoelectricenergyusedfortherefrigerationcompressor.Ingeneral,thewasteheatextractedatthecondensersidehasatemperaturethatistoolowtobeuseful.Applicationofanadd-onheatpumpgivestheopportunitytoefficientlyupgradethewasteheattoausefultemperaturelevel.



4.4 Pasteurisation

Productneedstobeheatedabove70°Cforpasteurisation,afterwhichiscooled.Mostpasteurisersutiliseheatexchangebetweenthecoldandhotproductflows.Thecoldproductbeforepasteurizationisusedtopre-cooltheproductdirectlyafterpasteurization,orlookingatittheotherwayaround:thehotproductisusedtopre-heatthecoldproduct.Inadditiontothisextraheatingandcoolingareneededforpasteurization.Thisisnormallyprovidedby,forexample,steaminjectionandaflowofchilledwater.Inmanysystems,theefficiencyofheatrecoveryislow.Aheatpumpcanbetheidealsolutiontoextractheatfromtheproductthatneedstobecooledandsupplythisheatatahighertemperaturetotheproductthatneedstoreachpasteurizationtemperature.

Thefigurebelowshowsatypicalmilkpasteuriser.Milkcomesinat10°Candispreheatedto62°Cdegreeswithregenerativeheatfrommilkbeingcooledafterpasteurisation.Themilkisthenheatedto72°Cwithhotwater,oftenproducedfromasteamheater.Afterthisdesiredpasteurizationtemperatureisreached,themilkneedstobecooleddownbackto10°C.Atfirstcoolingissuppliedbyregenerationwithfreshmilkto20°C.Toreachthedesiredmilktemperatureof10°C,acoldwatercircuitisused.Thiscircuitiscooledwiththeuseofarefrigerationsystem.Thecoolingcircuitreleaseswasteheatatitscondensersite.

Figure16–Conventionalpasteurizationprocess


Pasteurizationwiththeuseofanadd-onheatpump

Applicationofaheatpumpenablestheopportunitytoreusethewasteheatfromthemechanicalcoolingsysteminthepasteurizationprocess.Theadd-onheatpumpreplacessteamforthepasteurizationprocess.Compressedgasesfromtherefrigerationinstallationhaveacondensationtemperatureof25to30°C.Theheatpumpcompressorincreasesthepressureofthegaseousrefrigerantfurthersothecondensationtemperatureisover80°C.Heatingforpasteurizationisthussuppliedbytheheatreleasedatthecondenseroftherefrigerationsystem.Aftercondensationoftherefrigerantintherefrigerationsystem,itspressureisreducedinsideanexpansionelementafterwhichtherefrigerantissentbacktotheoriginalcoolingcycle.



Figure17–Pasteurizationprocesswithadd-onheatpump




5 Commercialfeasibilityfactorsandbarrierstoimplementation

5.1 Commercialfeasibilityfactors

Heatpumpscanbeusedinmanyindustrialprocessestoupgradeandthusrecoverwasteheatfromwastewaterstreams,hothumidair,andcondenserheatfromrefrigerationsystems,forreuseinprocessorcleaning.Wherewasteheatflowshavehighertemperaturesthanpotentialuses,directheatexchangeispossible,andaheatpumpisnotjustified.Wheretheusersneedheatathighertemperaturethanisavailablefromawasteheatstream,thenitcouldbefeasibletouseaheatpump.Incomplexindustrialapplications,apinchanalysismayberequiredtoassessthesuitabilityofwasteheatintegration.(SeeAppendix E: Pinch analysis,whichprovidesadditionalinformationonthisapproach).Forlesscomplexapplications,themethodfollowingwillhelpevaluatethebenefits:

Overalleconomicsofheatpumps

Theprimaryfactorsinfluencingtheeconomicsofheatpumpuseare:

• Therelativepriceofelectricityandavailablefuels(seenextsectionfordetails),ormoreaccuratelythedeliverycostofheatpumpservicescomparedtothosefromalternativeformsofheating.Theactualcompetitionisnotbetweenthecostofnaturalgasandelectricity,buttheeffectivedeliveredcostofheatatthetemperaturerequiredatthelocationitisneeded.Wheredistributedheatpumpsandotherdirectheatingcandisplaceaboilerandsteamsystem,thiscanreleaselargeamountsofhiddensavings,asthesesystemstypicallyhavelargelossesandsotheeffectivecostofdeliveringheattoaprocesscanbedeceptivelyhigherthanexpectedafteraccountingfortheselosses.Notethatnaturalgasboilersalsohavesignificantelectricityconsumptionforancillarieslikefansandpumps,whichisoftenforgotten.

Incountryareas,gastransmissionchargescanbeparticularlyhigh,ornaturalgasmaynotbeavailableandthenLPGorotherexpensiveheatsourcesareused,whichmakesheatpumpsmorecompetitive.Notealsothatrenewableelectricitygenerationon-sitecannowbecheaperthangridelectricity,andwillbecomeincreasinglyattractiveovertime.

• Thelifttemperatureoftheapplication(betweenthewastestreamtemperatureandtheprocessneed).SeeFigure20foranindicationofthiseffect.

• Thecapitalcostoftheheatpump,andtheinstallationcostoftheheatpumpasanewprojectorretrofit.Thecapitalcostwillbeimpactedbytheneedforredundancyforplantreliability.Onestrategytoachieveatleastpartialredundancywithoutacostpenaltyistoinstallmultiplesmallerstandardunitsinsteadofonelargeheatpump.Thiscanbemoreeconomicalasuseofmodular,massproducedheatpumpsmaydeliverunitcapitalsavings,andreducedmaintenancecostsfromuseofstandardisedequipmentandspares.

• Economicsofheatpumpsshouldfactorinallbusinessbenefits,notjustthevalueofenergysavings–seesectionbelowfordiscussionofbroaderbusinessbenefits.

• Financingoptions:whereaheatpumpisperceivedtohaveanunacceptablylongpaybackperiod,itmaystilldeliveraworthwhileinternalrateofreturn.And,iffinancecanbeaccessedatanacceptableinterestrateoveralongertimeperiod,theprojectmayofferapositivecashflowusingborrowedfunds.Anditsimpactonreducingoverallbusinessscostsmeansthatitcanalsoincreasebusinessassetvalueassoonasthesavingsarevisible.



Financiersarebecomingmoreinterestedinfinancingenergyproductivityandon-siterenewableenergyprojectsastheyimprovetheirunderstandingofthem.TheCleanEnergyFinanceCorporationhasplayedamajorroleinthechange,andpartnerswithfinancierstoofferattractivefinancepackages.

Heatpumpcostsshoulddeclineaseconomiesofscaleandstandardisationarecaptured,designersandinstallersbecomemoreskilledandsupplychainsmature.Timingofinstallationtomatchequipmentretirement,plantexpansion,developmentofnewplants,etc.canalsohelpeconomics.

• Theabilityoftheheatpumptosimultaneouslydelivermultiplefunctionse.g.heatingandcooling,orheatinganddehumidification,canenhanceeconomicbenefitsofHTheatpumps.

• Operatinghours–retrofittingheatpumpsisquiteexpensive,soagoodreturnoninvestmentisfacilitatedbyhighoperatinghours-ideally3shifts/7days(i.e.24/7operation).Alternatively,availabilityofcheapelectricityfromsolarPVandincreasingpeakdemandchargesmayimproveeconomicsforoperationswithlargelydaytimeoperatinghours,butthecapitalstillmustberepaidwithlessoperatinghours.Overnightandweekendoff-peaktariffscanalsoimproveeconomics.

• Theamountofwatervapourinawasteheatgasstreamfordryingapplications.

• Processefficiencyimprovementsimplementedinparallelwithinstallationofaheatpumpthatreducetheenergywasteoftheprocess.Thismayincludeupgradinginsulationofprocessequipment,installationofvariablespeeddrives,sensors,monitoringsystemsandcontrolstosupportsmarteroperation,optimisationofmaintenanceregimes,etc.Improvingprocessefficiencyreducesthesizeandcapitalcostoftheheatpump,aswellastheoperatingcost.

• Installationofrenewableenergyand/orenergystoragesystems(whichcanstorethermalenergy,notjustelectricity),establishmentofcontractstopurchaserenewableenergy,andcontractstomanagedemandandexportelectricity.Theseareoftencost-effectiveindividually,butcanachievesynergieswithheatpumpsandotherenergyefficiencymeasures.

• Therelativecapitalandoperatingcostsoftheheatpumpagainstalternatives,aswellasprocessandbusinessbenefits,discussedbelow.

• Also,asnotedearlier,ifaheatpumpcanprovidebothheatingandcooling,itsefficiencyisverysignificantlyimproved:andthermalstoragecanhelptomatchheatorcoolingavailabletodemand.

Understandingenergyproductivitybenefitsdeliveredbyaheatpumpapplication

Heatpumpscanoftendelivervaluetotheproductionprocessinadditiontoreplacingasteamheatingsystem.Anothersetofkeyeconomicdeterminantsofsuccesscomefromusingheatpumpstogenerateincreasedbusinessvalue.Formanyapplicationstobeattractiveandcommerciallysustainable,heatpumpswillnotonlyberequiredtoeffectivelyrecoverwasteheat,butwillalsoneedtodeliversomelevelofbroaderbusinessbenefit.

Thesebenefitsmayincludeenabling:



• Improvedplantreliability(partiallydependentonredundancy)• Reducedsystemmaintenance(particularlywhereitdisplacedallorasignificantpartof

steamreticulationsystem)• Enhancedcontrollabilityleadingtoimprovedproductquality• Increasedthroughput• Reducedwaterbills,wheretheheatpumpcondenseswaterthatcanbeutilizedon-site• Reducedenvironmentalmanagementcostse.g.boilerblowdownandchemicals.• Spacesavingscomparedtoaboilerandsteamsystem• Improvedworkingconditions–lessnoiseandheat

ThismaybeachieveddirectlythroughapplicationofthetechnologyorthroughenablingthepartialANDultimatelycompletereplacementofcentralsteamandhotwatersystems(Industry1.0)withhighlyautomatedlocalheatingsystemsusingheatpumpsandotherhighlyproductiveelectro-technologieswithhighlevelsofrealtimemonitoring,smartcontrolandoptimization(industry4.0).Combininginstallationofaheatpumpwithprocessefficiencyandothermeasures,asnotedearlier,canamplifytheoverallbusinessbenefits.

Figure18–TransitionfromIndustry1.0toIndustry4.0

Source:https://en.wikipedia.org/wiki/File:Industry_4.0.png

Othercapitalandrelatedmaintenancebenefitsthatshouldbetakenintoconsiderationinanevaluationofaheatpumpproject

Therecanbeacaseforinstallationofaheatpumptoreplacespecificprocessesorpartsofasteamsystemwherelossesareparticularlyhigh(forexample,processesattheendoflongsteampiperunsorpoorlyinsulatedpipes),orwheretimesofusediffer(forexample,requiredforlongeroperatinghours)fromtimeswhensteamisneededforotherprocessesandthesteamsystemcouldbeshutdownifthisprocesswasconvertedfromsteam.Notealsothatwherecondensatereturnfromprocessestoboilersinvolveslongpipes,theuseofpoint-ofenduseheatpumpstoreplacecondensatereturnmaybeworthwhile.Iftheplanthaslimitedsteamcapacity,forexample,duetoaneedtoincreaseproduction,theremaybeadditionalvaluegeneratedbyuseofheatpumpsinpartsofasystem,andotherenergyefficiencyimprovementstrategies.



Aheatpumpcanalsoavoidthecostoftheinfrastructure(andenergyuseoffansorpumps)toremovewasteheatandhumidairfromaprocess.Itcanprovidepotentiallyusefulwaterthroughcondensing.Itmayreducecostsofmeetingenvironmentalstandards(forexample,odoursorliquidwastes)byrecirculatingairorcondensingwaterinsteadofexhaustingit,andprovideforimproveddryerproductqualityfromeffectivelyconvertingthedryertoaclosedprocessasmake-upairisnotrequired.

Theimpactofrelativeenergypricesofelectricityandfuelsondirectenergycostsavings

Figure19–RelativecostofelectricitytogasinEuropeancountries

Figure20belowisadaptedfromtheUSDepartmentofEnergy1togiveanindicationoftherelativecostsofheatingliquidsusingboilersandheatpumps.Ascanbeseen,theeconomicsisheavilyinfluencedbytheamountthatthetemperatureistobeincreasedbetweentheoriginalwasteheattemperatureandthetemperaturerequiredbytheultimateprocess,thatis,thelift.Thehigherthelift,thelowertheCOPandtheworsetheeconomiccaseforusingaheatpump.

TypicalnewcontractindustrialelectricitypricesintheeastcoastofAustraliain2017/18are15-17.5c/kWh,afterrecentenergypriceescalation.Note:whereaplanthasinstalledPVtheiraverageelectricitypricecanbelower,particularlyifalargerproportionofplantoperatinghoursareindaytimeandgridelectricitycontractsincorporatepeakdemandchargesandtimeofusepricing.

TypicalindustrialgaspricesineastcoastAustraliain2017/18are$10-$12/GJandoftensignificantlymoreforsome2017contracts,afterdoublingduetosupplyconstraintsbroughtonbyhighLNGexportsfromGladstone.

Duetogaspriceescalationrelativetopowerinthelasttwoyearsandpotentialgasshortages,fora40oCliftintheexampleinthediagramwitha16.5c/kWhpowerprice,heatwouldbegeneratedatsay$7.75/GJbyaheatpump.Thiscanbecomparedtoanalternativegasboiler:atagascostof

1https://www1.eere.energy.gov/manufacturing/tech_assistance/pdfs/heatpump.pdf

Country RatioAustria 2.74803Belgium 2.68827Bulgaria 1.81882CzechRepublic 3.28846Denmark 1.34661Estonia 2.41489Finland 1.62201France 2.0554Germany 2.21645Hungary 2.69643Ireland 2.13351Italy 3.93987Latvia 3.09091Lithuania 2.89744Luxembourg 1.49882Netherlands 2.44648Poland 2.56748Portugal 2.21408Romania 2.90667Slovakia 3.14368Slovenia 1.74831Spain 2.78157Sweden 1.43411UnitedKingdom 3.62963

ThistableshowstherelativecostofelectricitytogasinEuropeancountries(2015).Thelowertheratio,thebetterthecompetitivepositionforusingheatpumps.TheratioinEastcoastAustraliaiscurrently3.3-4,dependingonthespecificpricesavailable.AscanbeseenthisratioisstillhigherthanmuchofEurope,butsubstantiallylowerthanithasbeeninthepast.

Notethatthistableisjustaguidetorelativedeliveredenergycosts,anddoesnotaccountforsteamsystemefficiencies,andinAustraliathiswouldtypicallybesignificantlyworsethancountrieslikeGermany.



$12/GJandevenassumingahigh75%efficiencyfordeliveryofheatfromtheboilersystemtotheapplication,thiswouldresultinacostofheatdeliveredofover$16/GJ.Evenifyourequireda60oCliftandtheheatpumpCOPwasthusloweroramoreexpensivemulti-stageorcascadedheatpumpwasneededtoachievehighefficiency,theeffectivecostofheatdeliveredfromtheheatpumpwouldbeabout$11/GJ,significantlycheaperthanthedeliveredheatfromthegas-basedsteamalternative.

Figure20–Heatpumptemperatureliftversuscostofdeliveredheat

Adaptedfrom:USDepartmentofEnergyhttps://www1.eere.energy.gov/manufacturing/tech_assistance/pdfs/heatpump.pdf

Theefficiencyoftheconversionanddeliveryofheatfromgas(orotherheatsource)isalsoaverysignificantfactorinthecomparison.Manyboilersystemsrunatunder50%efficiency,effectivelymorethandoublingthecostofheatrelativetothegasprice.

Note:Becautiousaboutsimplisticcomparisonoftheratioofgastoelectricitycostasadeterminantoflikelyprojecteconomicsasthisapproachcanleadtorejectionofapotentiallyprofitableapplicationofheatpumps.Systemsthinkingthatcombinesimprovementofend-useefficiencytoreducethesizeoftheheatpumprequired,ortakesadvantageofuniquefeaturesofheatpumpscanmakeabigdifferencetoheatpumpcosts.Useofcascadedormulti-stageheatpumpsandMVRcouldalsoworkbetterthanasinglestageheatpumpwherebiggertemperatureliftsarerequiredorwherehigherefficiencycanbejustifiedduetohighcostsofalternativeheatsources.

Anotherwayoflookingataverybasiccomparisonfortheoperationalcoststoheatwater:



HotWaterRequirement

EnergySource

Efficiency:AvgCOP

EnergyConsumption

CostofSource

CostofHotWater

Requirement

HeatPumpsavings

1KWh NaturalGasBoiler

0.33-0.8delivered

1KWh/0.8=1.25-3KWh

$12/GJ=$0.0432/KWh

1.25-3kWhx$0.0432/kWh=$0.054-0.13

1KWh WaterCooledHeatPump

6.0 1KWh/6.0=0.167KWh

$0.15-$0.18/KWh

0.167kWhx$0.15-$0.18/kWh=$0.025-$0.03

44-75+%AtCOP4,17-50+%



CO2footprintreduction:HotWaterRequirement

EnergySource

Efficiency:AvgCOP

EnergyConsumption

CO2SourceEmissions*

CarbonFootprint

HeatPumpCO2

footprintreduction

1KWh NaturalGasBoiler

0.9difffromprevioustable

1KWh/0.9=1.11KWh

185gCO2/KWh

1.11KWhx204gCO2/KWh=226gCO2

1KWh WaterCooledHeatPump

6.0 1KWh/6.0=0.167KWh

1090gCO2/KWh–VIC

840gCO2/KWh–NSW&ACT

780gCO2/KWh–QLD

530gCO2/KWh–SA

0.167KWhx1090gCO2/KWh=182gCO2–VIC

0.167KWhx840gCO2/KWh=140gCO2–NSW&ACT

0.167KWhx780gCO2/KWh=130gCO2–QLD

0.167KWhx530gCO2/KWh=89gCO2–SA

-11%VIC

-31%NSW&ACT

-36%QLD

-56%SA

Greaterwhereelectricityisfromrenewables

Note:whileofficialNGGIdatasuggestsTasmaniahaveverylowemissionintensity,thisisanaveragevalue.Atthemargin,theBasslinkcablelinksTasmaniaintotheNationalElectricityMarket.Achangeinconsumptionofaunitofelectricityleadstoareduction(orincrease)inproductionofaunitatthemarginalgreenhouseintensityoftheNEM.

NotethatacrosstheNEMastherenewablepowercomponentgrows(expecting42%by2030),thecarbonsavingsfromusingheatpumpswillgrow.However,atfringeofgrid,andattimesofpeakdemand,higherpowerlinelossesincreasethecarbonintensityofelectricity,especiallywhereSWERlinesareinvolved.Iftheplantusedallrenewableenergyfromsolar(plusbatteries)thenthecoefficientwouldbezero.NotealsothatiftheCOPislower,thenCO2savingsarelower(exceptintherenewablescases).



Theextrabenefitsthatcanaccrueifyoucancompletelyreplacecentralisedsteamsystems,usingheatpumpsandnon-thermalprocess:

Whileheatpumpsystemsareinherentlyefficientduetotheirabilitytoutiliseatmosphericorwasteheat(relativetoabasetemperatureofminus273C)andupgradeitwithleverageusinganelectricmotor,thereisanothercompellingefficiencybenefitwherelocaldistributedheatingcanbeimplementedwhichissuitedtospecificapplications.Throughthis,centralisedboilerandsteamdistributionsystems(usingnaturalgas/otherfossilfuels)canbedisplaced.Localapplicationoftenmeansthatwasteheatcanberecoveredfromaprocess,itstemperatureupgraded,anditcanbereusedinthesamelocation.Thiscanavoiddistributionlossesandfacilitatemorepreciseandflexiblemanagement.

Whytransitionfrom“Industry1.0”(thesteamage)to“Industry4.0”(automation,highcontrollability,realtimeprocessmonitoringandoptimisationandhighquality):

Steamsystemsarenotoriouslyinefficient.Theyhaveexcessivelossesinmostcasesduetopoorinsulationoflines,failuretorecoverallavailablecondensate,condensateheatlosses,boilerblowdownlosses,leakingsteamtrapsandsteamleaks.Boilersthemselvestypicallyhave15%+lossesinfluegasesandradiationlosses,unlesstheyhaveinstalledcondensingeconomisersandarekeptinverygoodtuningwithfluegasmonitoringandcontrolsystems.Theyalsosufferturndownandcyclinglossesatlowerloadsandrespondslowlytochangedoperatingconditions.Standbylossesarealsotypicallysignificant.So,fewcentralisedboilersystemsaremuchmorethan60%efficient,andsomebarelyachieve25%efficiencyoverall,thoughthisisseldomrecognisedduetolackofgasandsteammonitoringanddata.

Steamsystemsalsohaveconsiderablemaintenancecostsandimpactsonplantreliability.Itisalsonotrecognisedoftenthattherearesubstantialelectricitycostsassociatedwithboilerfans,pumps,andotherancillaries.

Usingelectricheatpumpsdesignedforspecificheating/coolingloads,installedlocallytotheseapplications,meanssimplifiedoperationscanbeachievedwithverymuchhigheroverallsystemefficiencies.

Avoidingtheneedforsteaminsomeapplications,particularlyremotefromboilers,canmeanthatsomesteampipescanbedecommissioned,reducingpipelosses.Andreducingtheneedforsteamreducesenergywastedfromprovidingheatatfarhighertemperaturesthanareoftenneeded.



Figure21–Infrastructureinafactoryusingdistributedheatpumps

Thisdiagramshowshowaseriesoflocalheatpumps(inthebottomhalfofthediagram)canbeusedtodisplaceanentireboilerandsteamsystemincludingallthetraditionalinfrastructure(topquarterofthediagram)inafoodprocessingplant.(Notethatinthiscasethesteamboilerpre-heatedbytheheatpumpseemswasaboosterforthesmallloadlefttosupplyalegacyprocessstillneedinghightemperaturesteam).

Intheoriginalcasesteamisproducedintheboilersintheenergycentre,andsuppliedtoallareasofthefactoryforuseinthemanufacturingprocess.Overallenergyefficiencyislow,duetoboilerlosses,heatlossesfrompiping,steamleakagelossesintraps,anddrainrecoverylosses.

SignificantenergysavingsareachievedbyreplacingsteaminfrastructureandelectricresistanceheaterswithdistributedHTheatpumpsforhotwater/airsupply,heatingofcirculatinghotwaterandsteamgeneration.Heatrecoveryandsimultaneouscoolingandheatingusingofwasteheatusingheatpumpsisalsoutilized.

Itmaynotbenecessarytoreplaceawholesteamsysteminonegotogainsomebenefits–forexamplebyusingaheatpumptoreplacealongsteamandcondensatepiperun(orachilledwaterorglycolpipetoaremotepartofasite),substantialreductioninlossesmaybeachieved.

Potentialbenefitsfromusingthermalstoragewithheatpumpsystemstodeliverdemandmanagement

Ifheatgeneratedwithheatpumpsorwasteheatexhaustedinplantscanbestoredinaheatstoragematerial,theeffectiveuseandcontroloftheheatisenabled.Daytime(peaktime)andnighttime(off-peaktime)powerloadscanberebalancedorthestoragecanbeusedtosupportdemandresponse,andwasteheatmaybefurtherutilized.Thermalenergycanbestoredduringdaytime



heatpumpoperationonsolar,foruseatnightorwhensolarinputislower.Atpresent,wateroricearenormallyusedasthermalstoragematerials.However,thermalstoragematerialssuchasmoltensalt,organicmaterialorhydratedsaltcanstoreheatoverawidetemperaturerangefrom-10to250°C.PhaseChangeMaterials(PCMs)areimprovinganddecliningincost.Theycanreducethestoragevolumeneeded,anddeliverheatatafairlystabletemperatureastheysolidify.

Figure22–Heatpumpwithoutthermalstoragetank

Figure23–Heatpumpwiththermalstoragetank


Heatpumpsandrenewableenergy

Heatpumpsofferseveraladvantagesoversolarthermaltechnologies.Theycanrunonelectricityfromanysourceincludingthegrid,sotheycanbeintegratedintothecoreproductionprocessesofaplant.Theyalso‘feedoff’lowgradewasteheatsources,reducingtotalenergyinputstoprocesses.Heatpumpsworkconsistently:cloudsorcoldwinterweatherhavelittleimpactontheirperformance.

Heatpumpscanbemodular,andbenefitfromeconomiesofscaleforproductionandinstallation.Theskillsrequiredtomaintainthemaremorewidelyavailablebecausethecanusetherefrigerationindustry’slabourforce.Byusingtwoormoreunitsinparallel,reliabilitycanbeimproved,aslossofa

100%



singleunitwillonlyreduceoutput,notleadtoaplantshutdown.Also,becauseheatpumpsaremorelikelytobedistributedaroundaplant,theycanofferhigherreliabilitythanacentralboiler.Manyplantsalreadyhaveback-upgenerators,whichcanbeusedtokeepheatpumpsoperating(andprovidewasteheattoimprovetheirefficiency)attimesofgridoutagesorlimitedsupplyduringpeakelectricitydemand.

Heatpumpscanworkwith,andenhancetheeconomicsofrenewableenergy:

• HeatpumpscanrunonsolarPV,wind,bioenergygeneration,storedelectricityorthegrid,sotheycanbeintegratedintoanon-siterenewableenergysystem,ordrawpowerfromregionalwind,hydro,pumpedhydroorotherelectricitysupply.Biofuelsorsolarthermalsystemscanbeusedtoraisetheinputtemperaturetoheatpumps,improvingtheirefficiency,or(withbiofuels)to‘topup’heatpumpoutputtodeliverhighertemperatures.

• Lowcost,massproduced,efficientsolarthermalcollectortechnologiescanbeused,insteadofmorecomplexandlessefficienthightemperaturecollectors,toproducelowtemperatureheatthatcanbeupgradedbyheatpumps.Wheresolarthermalsystemsraisethetemperatureofwasteheatfromon-sitesources,theyimprovetheefficiencyofaheatpump,sotheircontributionhelpstoincreasetheheatoutputfromtheheatpump.Itischeaperandeasiertostorelowgradeheat(atunder100°C)asaninputforheatpumpsthantostorehightemperatureheat.

Capitalcostofequipment

Itisdifficulttoprovidegenericcapitalcostsandeconomicanalysisasheatpumps’specificationsdependonthetemperatures,andtheinstallationcostscanvarygreatly,particularlyretrofits,butthefollowingprovidessomeguideonorderofmagnitudecosts.Thisdiscussionmustbeseeninacontextofpotentialforsignificantpricereductionsthrougheconomiesofscale,learningbyinstallersandongoingtechnologydevelopment.Withexperience,theperceivedbusinessvalueofthebroadbenefitsofheatpumps,andperceptionsofriskmaychange,nichemarketsmaybeidentified,anddevelopmentoftailoredfinancingpackagescouldunderpingreatadoption.

Oneimportantissueistheneedforplantredundancy,whichwouldberequirediftheoriginalheating(andinsomecasescooling)systemwasnotretainedforstandby.Ifyouwerestartingfromscratchwithadistributedheatpumpsystemandnofossilfuelboilersystem,youwouldneedredundancy,lowercostbackuporotheroptions,butyouwouldsavethemarginalcostbetweenthedistributedsystemandthesubstantialcostofinstallingacompleteboilerandsteamsystemwithassociatedheatexchangersandpipinginfrastructure.Also,theuseofmultiple,smaller,standardisedpackageheatpumpunitsmayprovideamoreeconomicalsolutionthanalargecustomisedunitandalsoprovideredundancy.Wherebothheatingandcoolingareneeded,theCOPofaheatpumpsignificantlyimproves,soitseconomicscanimprove.

MayekawasuppliesapackagedCO2transcriticalEco-Cutehotwaterheatpump(upto90oCwater),withabout90kWheatingcapacitycostsabout$75,000plusinstallation–somaybe$100,000-125,000installedinaretrofit.ThereisoneinstalledinaTofuplantinAustralia.MayekawaalsosuppliesR717heatpumpscapableofproducinghotwaterupto80oCinlargerquantities.TheyalsolocallysupplyCO2trans-criticalunitsthatheatairto120oC,alsoaroundthe$75,000markplusinstallation.JohnsonControlssuppliesammoniaunitsinAustralia.Alargescalehotwaterunitinstalledsupplyingwaterat70oCwas$300,000.



MitsubishiHeavyIndustriesoffersa30kWCO2refrigerantheatpumphotwaterservicewithaCOPof3-4forcommercialandsmallindustrialapplications.Thesecostaround$25,000,andareattractivereplacementsforLPGhotwaterservices,asrunningcostisfrom40to60%lower.Theyarenotdesignedtoutiliseheatrecoveryorprovideactivecoolingwhileheating.

ThepaybackforsomeprojectsinEuropeisaroundtwoyears.InAustralia,thebestprojectsarelikelytocomeinaround2+yearspaybackonenergycostsavingsalone,butasseenintheprevioussectionwehaveahigherelectricitytogaspriceratioinAustraliathanmanycountriesandwewouldexpectpaybacksheretotypicallybemorelike4years,withalotofvariability,andpotentialforimprovementinfuturewithcostreductionsduetohighersalesvolumes.NotealsothatthesepaybacksdoNOTincludetheimpactofenergyproductivityenhancingvaluestreams,nordotheyaccountforadditionalefficiencybenefitsthataccruefromreplacementofpoorefficiencysteamsystems(orpartthereof).Developmentoffinancingschemesthatcouldprovideequipmentwithlittleornoupfrontcostandapositivecashflowcouldincreaseadoptionrates.

TheAustralianRenewableEnergyAgency(ARENA)hasreleaseditsnewInvestmentStrategy,andenergyproductivityisoneofthefourkeypriorities.ARENAwillbelookingforgoodprojectsthatshowinnovationinthecontextofAustraliaandanindustry,andalsowherethereisgoodreplicationpotential.TheinitialapplicationsofhightemperatureheatpumpsforindustryinAustralia,particularlyinnewapplications/industriesforthiscountry,potentiallyfitthebillandcouldbeabletoapplyforgrantsofupto50%oftheinstalledcapitalcostoftheproject.

Somestategovernmentsarealsoprovidingfundingthroughspecificprogramsaswellasbroaderapplicationoftheirenergyefficiencycertificateschemes–thoughusuallytheseschemesdonotofferincentivesforchangingenergyforms.Well-designedheatpumpsystems,especiallythosecombinedwithprocessefficiencyimprovements,candelivercarbonemissionreductions,thebasisonwhichthesizeofincentivesiscalculated.Wewillneedtotesttheabilitytoapplyforfundingforheatpumpapplications.

Maintenancerequirements:Hightemperatureheatpumpshavetendedtohavegreatermaintenancerequirementsthanlowertemperatureunitsasthehighertemperaturesrequirehighersystempressuresandthusputahigherstressoncomponents.InspectionsarerequiredtwiceannuallyandrecommendedreplacementperiodsforsmallpackagedHPcompressorsare30,000hours(about4yearsifrun3shifts,7days)atacostforasmallpackagedcompressorunitofabout$25k.Ongoingevolutionofremoterealtimemonitoringanddataanalysisofferpotentialtoreduceorfacilitateimprovedcoordinationofroutinemaintenancevisits.



5.2 Barrierstoimplementation

Thefollowingisabriefassessmentofthekeyissuespreventingthelargerscaleimplementationofhightemperatureheatpumpsinthefoodindustry.

1. Lackofawarenessandknowledgeofhowtoachievethemosteconomicallyattractiveapplications:Basedoninterviewswithstakeholders,mostmanufacturingbusinesseshaveverylimitedknowledgeofhightemperatureheatpumpsandpotentialapplications.Onelargeandsophisticatedfoodproducerheldaphoneworkshopwithkeystaffanda2xEPresearcher,andidentifiedhalfadozenveryprospectiveopportunitiesinhalfanhour,noneofwhichhasbeenexploredpreviously.Thefactthatgasandelectricitypriceshaveonlyreachedapointwhereheatpumpshavebecomeeconomicallyattractiveinthelastyearisamajorreasonforthislackofawareness.

Wealsoseeevidenceinthelocalmarketofsimplisticassessmentsofheatpumpapplicationswherethetotalbusinessvalueforimplementingthemisnotunderstoodandonlythedirectenergycostcomparisonsfortheapplicationareassessed.

2. Capitalcost:Heatpumpprojectsrequirecapitalinvestment.Australianmanufacturerstypicallyhaveshortpaybackrequirementsandexhibitverylowlevelsofcapitalinvestmentintheirfacilities,andthisactsagainstretrofittingheatpumps.Financialanalysisalsorarelyincorporatesthevalueofthepotentialmultiplebusinessbenefits,asthisrequiresmoresophisticatedanalysis.Theperceptionthatabusinessis‘behind’untilthepaybackperiodisreachedisalsoapervasivebarriertomanyenergyproductivityinvestments.Inpractice,theseinvestmentscanincreaseassetvaluebyamultipleofpurchasecostso,ifthebusinesswassold,itwouldgainahigherprice.Anadditionalpotentialcapitalcostistheneedforequipmentredundancyintheidealsituationwheretheexistingheating/coolinginfrastructureisnotgoingtoberetained,forexample,inthesituationwhereaboilerandsteamsystemarebeingreplacedbydistributedlocalheating.Thisisnotanissuewheretheequipmentselectedfortheapplicationismultipleidenticalpackagedheatpumps,andthisislookinglikethemosteconomicaloptioninmanycases.Boilersalsoneedredundancybutthiscapitalcostisgenerallyalreadysunk(andnotethatstandbyboilerstendtohavemuchbiggerstandingheatlosses.

3. Lackofenergyefficiencyincentivesandgovernmentpromotion:ConfusingandrapidlychangingpolicysettingsataCommonwealthlevelandalackofincentivesandpromotionofheatpumpshashamperedapplicationofthistechnology.

InJapanandSouthKoreathistechnologyhasbecomewidelyappliedinindustrybasedonstrongandconsistentlongtermsupportforthedevelopmentandtechtransferofheatpumps.

4. Abusinessculturewhichdoesnotencourageinnovationandchange:AstherearefewinstallationsinAustralia,andlackofanexperiencebase,manycompanieswouldperceivehigherriskfromtheseinstallations.Inaddition,togainthegreatestbenefitfromdistributedhighenergyproductivityelectricitytechnologies,ideallyyouwouldaimtoreplacecentralboilersandsteamsystemsentirely,butthiswouldrequireafurtherleapoffaithandAustralianbusinessesgenerallyarehighlyriskaverse.Technicalprofessionalsalsolackexperienceandrelevantskills:thisreducesthelikelihoodofthemrecommendingheatpumps.

About 15 to 20 years ago, several reports (for example, Industrial Heat Pumps – Experience,PotentialandGlobalEnvironmentalBenefits,IEAHeatPumpCentre)pointedouttheadvantagesof



industrial heat pumps and quoted the technical and economical performances of various types.Disadvantagesandobstaclesforapplicationswerealsoidentified:

• Lackofknowledgeofthepotentialbenefitsofindustrialheatpumps• Lackofexperienceindifferenttypesofindustries.• Lackofhardwareforsometypesofpotentialapplications.• Lackofcombinedprocessandheatpumptechnologyknowledge(or,lackofunderstanding

ofprocessintegration).

Manyof the sameargumentsapply todayoutside JapanandSouthKorea,whereapplicationsareverycommoninthefoodindustry.

Thelastpointonlackofunderstandingofprocessintegrationisimportant,aswhenheatrecoveryispartofaheatpumpretrofitproject–andparticularlyinthecaseofsimultaneousheatingandcoolingapplications,togetthebestoutcomes,apinchstudyshouldbeconductedandthesethermodynamicengineeringskillsandexperienceareinshortsupplyinAustralia(seeAppendixE:Pinchanalysis).Thisunderstandingwouldovercomethesimplisticdrivetowardsplantchangeoutdecisions.

Otherpotentialbarriers:

• Lackoflocalexperienceandinfrastructure.WhilethereareatleastfourcompaniesthathavecomeforwardinstakeholdermeetingswiththeinterestandtheoreticalcapacitytosupplyhightemperatureheatpumpsinAustralia,thereareonlyarelativelysmallnumber(probablylessthanfive)ofinstallationsintheAustralianfoodindustry.Thismeansthatthereislimitedlocalexperienceinthespecification,installationandmaintenanceofthemachinesinAustralia.

• Technicalcompetencyrequiredtoidentifyoptimalapplications.Tofindtheidealapplicationsforheatpumpsthefollowingskillsareoftenrequired:

o Pinchanalysistodefinethebestplacetolocateheatpumpstogainthebestoutcome,particularlytofindsimultaneousheatingandcoolingapplications.

o Businessunderstandingtodefinethevaluestreamsfromtheprojectsontopofthebasisenergysavings.

• Abilitytoeffectivelyschedulecombinedheatingandcoolingduties.InsituationswhereheatpumpsgainthemaximumCOPbycombiningheatandcoolingduties,theremaybechallengesschedulingbothdutiesunlessinthesameprocess(likeapasteuriser),withoutinstallationatadditionalcostofhot/coldstoragetanks.



6 Industrialapplicationsandcasestudyexamples

6.1 Sampleinternationalindustrialapplications

6.1.1 HeatpumponaFrenchfrydryer

AmanufacturerofFrenchfriesinstalledaheatpumpthatwillprovidetheheatforaFrenchfrydryer.Abeltdryerthatoperatesatatemperatureof70°Cisusingitsownwasteheatduetotheuseofaheatpump.Asaresult,anenergysavingupto70%isrealizedintheenergyconsumptionofthedryer.Source:DeKleijn2017,www.industrialheatpumps.nl

6.1.2 Add-onheatpumpinthefoodindustry

Ataleadingcompanyinthefoodindustryaheatpumpisinstalled'ontopof'anexistingrefrigerationsystem.Thisconstructioniscalledanaddonheatpump.Itisamechanicalheatpumpthatusestherefrigerantofanexistingrefrigerationsystem,inthiscaseAmmonia.WiththeuseofanaddonheatpumpthepressureofthegaseousAmmoniaisincreased.Thiscausestherefrigeranttocondensateatahighertemperature.Inthiscasetheaddonheatpumpisusedtoheatawatercircuitupto65°C.Applicationofaheatpumpenablesseveralprocessestobenefitfromthewasteheatoftherefrigerationsystem.Source:DeKleijn2017,www.industrialheatpumps.nl

6.1.3 Hybridheatpumpatslaughterhouse

AtaNorwegianabattoir,ahybridheatpumpwith650kWofpowerwasinstalledin2007.Thehybridheatpumpisusedtoheatwatertoatemperatureof83°C.Thiswaterisusedforcleaningandsterilisationpurposes.Heatisextractedoutofarefrigerationinstallation.Installationofthehybridheatpumpresultedinanannualenergysavingof500,000litresofoil.Source:DeKleijn2017,www.industrialheatpumps.nl



6.1.4 Add-onheatpumpforsportscentre

Atasportscentre,anaddonheatpumphasbeeninstalled.Theadd-onheatpumpisusedtoupgradetheheatthatisrejectedfromofanicerinktokeeptheicesurfaceintact.Theheatistransportedtowardsaswimmingpool.Theinstallationoftheadd-onheatpumpwasmadepossiblebecauseofacollaborationbetweenauthorities,thecompanyandtheinstallerofheatpump.Theheatpump,installedJune2012,enablestheuseofwasteheatfromtheicerinkbyincreasingthepressureoftherefrigerantinitsrefrigerationsystem.Asaresult,moreenergyisavailableatthecondenseroftherefrigerationsystemthatcanbeusedintheheatingsystemoftheswimmingpool.Source:DeKleijn2017,www.industrialheatpumps.nl

6.1.5 Canadiandairyplant1

Figure24–CO2trans-criticalindustrialheatpumpinCanadiandairyplant



6.1.6 Canadiandairyplant2

Figure25–NH3heatrecoveryheatpumpinaCanadiandairyplant

6.1.7 Poultryprocessingandmeatpackingplants

Figure26–Combinedcooling/heatingusingheatpumpsintwoexampleapplications



6.1.8 Babyfoodprocessingplant

Figure27–Energy/watersavingsatbabyfoodplant

TherearemanymoreexamplesofindustrialheatpumpapplicationsinternationallyintheIEAAnnex35foundathttp://heatpumpingtechnologies.org/publications/application-of-industrial-heat-pumps-part-2/.

SeealsoAppendixB:Internationaltechnologyreviewforasummaryofaselectionofinternationalcasestudies.



6.2 Australiancasestudies

Asdiscussedthroughoutinthisreport,atpresentthereareveryfewexamplesofhightemperatureheatpumpsbeingutilisedintheAustralianfoodindustry.Severalcasestudiesarepresentedinthissection:LobethalAbattoirinSouthAustralia,whereaheatpumpwasinstalledin2012;SheneEstateDistilleryinTasmania,whereaheatpumpwasinstalledduringthecourseofthisprojectbeingconducted;andtwositesforwhichheatpumpinstallationshavebeenproposedandpreliminaryassessmentshavebeenconducted.ThefirstofthesesitesisafoodprocessingplantontheoutskirtsofMelbourneandthesecondisasaltprocessingfacilityinregionalVictoria.Furtherdetailedfeasibilityassessmentsareplannedforbothsites.

Lessonslearnedfromlocalexperience

ThefollowingobservationshavebeenmadeabouttheheatpumpinstalledattheSouthAustralianabattoir:

• Theheatpumptendstohaverelativelyhighermaintenancecostandhighercapitalcostthantheboiler(thoughnotwhenyouconsiderthewholesteamsystem).

• Theheatpumpinthiscaseisanadd-onheatpumptothefreezercompressor,whichbecomesaproblemwhentheproductmixisfavouringchillednotfrozenproducts,sothefreezersarenotproducingenoughbasewasteheatfortheheatpumptorunatfullload.Theabattoirdoesnothaverenderingfacilitiesandassuchisnottypicalofmostlargeabattoirs,whichtendtohaveadequaterecoveredflashsteamfortheseheatingduties.Asaresult,heatpumpsaregenerallynotusuallyviableforsiteswithrenderingusingpresentapproaches.

• Themaximumhotwatertemperatureachievableis85oC;optimaloperationisat80oC.

• Thefollowingareoperationalexperiencegainedbysiteengineerswiththisparticularinstallation:

• Theheatpumprequiresastableloadtoensuregoodoperation–ideallysizedfor60to80%oftotalheatrejectionavailablefromrefrigerationplant.

• Heatpumpcontrolsonmainplantdischargepressure,notwateroutputtemperaturewhenloadfrommainplantisinsufficient.

• Planthadtoinstallautomaticisolationvalvesonbothinletandoutletofammoniaontheevaporativecondenserasincoldweatherthecondenserwasprovidingapproximately350kWofcondensercapacitythroughnaturalairflowwithnopumporfanrunning.

• Theorysaidsiteneededtheheatpumpsurgevessel3mabovethemainplantliquidreceiver,butinpracticetheyneededadirectliquidlinefeedfromtheheatpumpsurgedrumtothemainplantchilleraccumulatortoavoidliquidbackingupintheheatpumpsurgedrum.

• Itisveryimportanttohaveahighefficiencyairpurgerinstalledandoperating–carefuldesignandinstallationtoensureairisremovedfromtheheatpumpwithoutexposingairpurgertoexcesspressureasonlytakesasmallamountofairinthesystemtoshutdowntheheatpump.



• Ensureheatpumpcompressorsareonvariablespeeddrivestoalloweffectiveregulationofcapacity.

• Heatpumpreciprocatingcompressorsarenoisy–designenclosuretosuit.

• Complexprogrammingrequiredtoensureintegrationandoptimisationtomainrefrigerationsystem.

AstudyofanAustraliandairyplantassessedforheatpumpsuitabilityfoundthefollowing:

• Thedairyplantcharacterisedasatypicaldairyfactorywith18.8GJthermalload.Theassessmentwasforusingheatpumpstoreplacegasfiredsteamtoheatwaterfrom15to60oC.Theassumedgaspricewas$11/GJ(thoughsomesitesarenowpaying$15/GJ).

• Theassessmentresultswere6-8yearpayback.(Thisisbeyondthe2-4yearpaybacktypicallyexpected.However,itisequivalenttoarateofreturnoninvestmentof10-15%pa:withappropriatefinancingandriskmanagement,thiscouldbeviable:indeed,thisrateofreturnwouldbeconsideredacceptableforlargeenergysupplyinvestments.)Othernegativesincluded:complexdesign;difficultymatchingdemandwithsupplyofwasteheat;andincreasedelectricaldemand(thoughthiswaspresumablyincludedinthefinancialcalculations).

WhatwasNOTincludedintheassessmentonthepositivesideisfurtherbenefitssuchasthermalsavingsfromreplacingallorpartofthesteamreticulationsystem,opportunitiesforsimultaneouscoolinganyproductivitybenefitsfromusingfarmorecontrollablelocalheating,andpotentialsynergiesfromcombiningaheatpumpwithenergy(thermaland/orelectric)storageandrenewableenergy.



6.2.1 LobethalAbattoir,SouthAustralia

Contextofheatpumpinstallation

• ThomasFoodsInternational’sLobethalAbattoirislocatedapproximately35kmwestofAdelaide.

• In2012atwostageammoniaheatpumpwasinstalledtoutilisewasteheatexpelledbythecondensersofnewfreezerplant.

• Heatpumpheatsapprox.250,000Lofwater/dayfrom11°Cto75°Candisanalternativetoheatingwaterwithagas-firedboiler.

• Hotwaterproducedisdeliveredtoathermalstoragetankandisusedpartlyduringthenightforsterilisationandcleaningpurposesandpartlyduringthedayforprocessinge.g.sterilisingknives.

Equipmentinstalled

• MayekawaPlus+Heatammoniaheatpump

• COP:4.8–6.5

Costsandbenefitsofheatpumpcomparedtogasboiler

• Costtosupplyandinstall630kWhighstageammoniaheatpumpontoanexistingrefrigerationplantsimilartoLobethalapproximately$900,000+GST*

• FirstofkindinAustralia,sohighR&Dcostsincurred

• Energycost:40%reductioninLPGcostsinlinewithreductioninLGPuseforwaterheating

• Wateruse:reductioninwaterevaporatedinevaporativecondensersbyasmuchas119kLperweek

• Carbonemissions:significantreductionof7tonneofCO2perweek

• Ammoniaisnon-ozonedepletingandhasaglobalwarmingpotentialofzero(ascomparedtoalternativessuchasthesyntheticrefrigerantR-134a,whichahasaGWPof1,300.Asammoniaiscausticleakdetectionsystemswereinstalledtominimisesafetyrisk.

Comments

• ItshouldbenotedtheLobethalAbattoirisdoesnotrenderingfacilities.Generallylowerviabilityforheatpumpinstallationsinabattoirswithrenderingfacilitieswithsurplusrecoverableheat.

• Astheheatpumpisdesignedtoutilisewasteheatfromfreezers,changesindemandfromfrozentochilledproductsimpactsoperationoftheheatpump.

*NotactualcostofLobethalheatpump–indicativecostsuppliedbyheatpumpinstallerColdLogic

Informationandimagesources:http://www.ampc.com.au/2010/07/Heat-Recovery-From-Refrigeration-Plant&http://155.187.2.69/atmosphere/ozone/sgg/equivalentcarbonprice/case-studies/pubs/cs-mayekawa.pdf;NektaNicolau,ThomasFoodsInternational



SupplementaryinformationregardinginstallationofaheatpumpsimilartothatinstalledatLobethalAbattoir

CourtesyofBradSemmler,Director,ColdLogic

Tosupplyandinstalla630kWhighstageammoniaheatpumpontoanexistingammoniarefrigerationplantwillcostapproximately$900,000plusGST.Thiswouldinclude:

• MultiplecompressorsonVSDwith50%redundancy• Soundattenuatedenclosure• Ammoniadetectionandventilationsystem• WiringandelectricalcontrolsystemwithaSCADAPC• Integrationtoexistingrefrigerationplantpipeworkandcontrols• Commissioningandspareparts.

Inadditiontothisthefollowingcostswouldneedtobeconsidered:

• Powersupplytotheunit–500amps• HighefficiencyAirpurgerontheammoniaplant$50,000installed• Hotwaterstoragetank–sizedependantonwaterdemand,refrigerationloadsetcasaguide

a50,000litreinsulatedtankwillbe$55,000• Hotwaterpipingtoconnecttoexistingsystem–sitedependant• Plantarea9mx4.5m,ideallylocated3to4maboveexistingliquidreceiver,canengineer

thisrequirementoutbutaddssomecost• Accesstoplantarea.

Inordertorealisethefullcapacityoftheheatpump,thebaserefrigerationloadneedstobeinexcessof500kWR.Thesystemcanrunoffanyammoniasystemwithasuitablebaseload.



6.2.2 SheneEstateDistillery,Tasmania

Contextofheatpumpinstallation

• SheneEstateisahistoricpropertynorthofHobartcontainingadistillerythatproducesginandwhiskyusingtraditionaldistillationpractices.

• Thedistillationprocessinvolvesheatingmaltedbarleymash.Eachday6,000litresofhotwaterisrequired,initiallyat90°C,withthetemperaturethenreducedtoapproximately64°Cto65°C,theoptimumtemperaturetodissolvesugarscontainedwithinthestarchofmaltedbarley.Finallythetemperatureisbroughtupagainto70°Cattheendofthemashinginprocesstodissolveenzymes.

• Theestateisnotconnectedtothegasgridandhasbeensubjecttoincreasingelectricityprices,providingtheimpetustoimproveenergyefficiency.

• Conventionallyhotwaterusedinthedistillationprocessisheatedusinganinstantaneouselectrichotwaterheater.

• Heatpumpinstalledinmid2017asanalternativemethodtoheatwater.

Equipmentinstalled

• 1x30kWMitsubishiHeavyIndustriesQ-tonC02air-to-waterheatpump.

• COP:2.8–4.3(perspecificationshttp://mhiae.com/products/heat-pumps/q-ton/specifications)

Costsandbenefitsofheatpumpcomparedtoelectricinstantaneousheater

• Heatpumpisamoreenvironmentallyresponsiblemethodofproducinghotwaterasitislessenergyintensivethaninstantaneousheaters.ExistingwaterheaterhasaCOPof1:48Kwinputand48Kwoutput.TheQ-tonhasachievedCOPof4.2:7Kwinputand30Kwoutput.

• Heatpumpischeapertorunduetolowerenergyuse.Anticipateenergysavingsof66.6%peryearcomparedtoinstantaneousheater.

• Heatpumpisabletoheatwatersignificantlyfasterthanexistinginstantaneoushotwaterheater,improvingplantefficiency.

• Capitalcost:approximately$30,000plusinstallationcostsapproximately$5,000.

• SheneEstatehasgoodqualityfilteredwater,thereforeenvisageminimalmaintenancerequirementsintofuture.

Nextsteps

• InvestigatinginstallationofPVandbatterysystemtofurtherreduceenergyconsumption.

Informationandimagesource:DavidKernke,Owner,SheneEstateDistillery



6.2.3 Foodprocessingfacility,Victoria

Contextofproposedheatpumpinstallation

• HeatpumpproposedforfoodprocessingplantlocatedinoutersuburbsofMelbourne.

• Currentplantequipmentincludes:1hotwaterboiler,1steamboiler,5Stalcompressors,2BACevaporativecondensers.

• Hotwaterboiler:15,700MJ/handoutlettemperatureof61oCforcleaninginplace(CIP).

• Heatrejectionoftherefrigerationplant(5Stalcompressors):1,210KW

• Wateruseintheevaporativecondensers:21,000l/day.

Equipmentproposed

• SABROEHeatPACwithreciprocatingcompressorandAmmoniaasrefrigerant.

• COP=5.5–7.5

• Intheproposedsystem,theheatpumpwillusetheheatrejectedbytherefrigerationplanttogeneratehotwaterforCIP.

Initialestimatesofcostsandbenefitsoftheproposedheatpumpcomparedtocurrentsystem

• EstimatedequipmentcostofSABROEHeatPACheatpumpof1,500kWof

heatingcapacityisapproximately$390,000(exclGST).

• Savingsduetoreducedoperatingcostsestimatedtobeapproximately57%.

• CO2footprintreductionsestimatedtobeapproximately27%.

• Reductioninwateruserelatedtotheevaporativecondensers.

• Reductionofchemicalcleaningofevaporativecondensers.

Comments

• InfoodapplicationswhereboththecoolingandheatcapacitycanbeusedthecombinedCOPincreasesconsiderably.

• Recoveringheatonthecoolingwaterhelpsreducechemicalandwateruse.

• Thehotwatercanbeusedfor:sanitaryhotwater,spaceheating,processheating,cleaning,disinfectinganddrying.

• Therearemanysourcestorecovertheheatandsinkcombinationspossibletousethehotwater.

• Whenaheatpumpisoperatingheatiskeptwithintheplantandnotrejectedintotheatmosphere.

• SABROEheatpumpsuseAmmoniaasrefrigerant,withzeroozonedepletionpotentialandzeroglobalwarmingpotential.

• Refrigerantcharge50%smallerthanconventionalheatpumps,becauseofspecialcondenser/evaporatordesign.

• Factory-assembled,pre-testedpackagedunitsbasedonSABROEreciprocatingcompressor.

Informationandimagesources:RicardoHoffmann,JohnsonControls;http://www.sabroe.com/en/products/chillers-and-heat-pumps/



6.2.4 Saltprocessingfacility,Victoria

Contextofproposedheatpumpinstallation

• HeatpumpproposedforsaltprocessingplantlocatedinregionalVictoria.

• Hotairat70°Cisrequiredtoevaporatewaterfromsaturatedbrinetocreatesaltflakesandothersaltproducts.

• Airiscurrentlyheatedusingconventionalelectricresistanceheaters.

• Atpresent17dryersareinoperation.Itisproposed8ofthesedryersarereplacedwithheatpumptechnologycoupledwithPVasapilot.

• Heatsources-

o Saltpond:

50°Cinsummerfor12hours

35°Cinwinterfor8hours.

o Groundwater:

16°Cto20°C.

Equipmentproposed

• MayekawaCO2HeatPumpEcoSirocco

• SaltpondheatsourceCOP:4.7-5.2

• GroundwaterheatsourceCOP:3.9-4.6

Existinghotairsystemtoberetainedasabackup.

Initialestimatesofcostsandbenefitsoftheproposedheatpumpcomparedtocurrentsystem:

• Heatpumpequipmentcostestimatedatapproximately$75,000+approximately$30,000forinstallation.

• Initialproposalalsoincludesinstallationof100kWofPVatanestimatedcostof$150,000.

• Energycostsavingsrelatedtoreducedenergyconsumptionestimatedtobeupto$160,000peryear(assumesplantrunning24hoursperday).o Equatestoanestimatedreductionin

energyconsumptionof45%.• Payback:2-3years.

Nextsteps

• Detailedfeasibilityassessmenttobeundertakenpriortofinaldecisiononconductingpilotbeingtaken.

Informationandimagesources:MikeOno/PeterO’Neill,MayekawaAustraliaPtyLtdandAbhijitDate,RMIT



7 Scaleofopportunity

Therapidlyrisingpriceofnaturalgasandpotentiallylimitedavailabilityinthenextfiveyearshasmadeheatpumpsmoreimmediatelyinterestingtothefoodindustrythantheyhavebeeninthepast.

ItisverydifficulttoputameaningfulnumberorevenrangeonthepotentialtotaleconomicalscaleofapplicationofHTheatpumpsintheAustralianfoodindustryforthefollowingreasons:

• TheeconomicsofHTheatpumpsaredependentonthespecificsoftheapplication,asdiscussedearlierinthisreport,including:thetemperatureoftheapplication;thesizeofthetemperatureliftrequired(relatedtoavailabilityofwasteheatasaheatsource);thepotentialforreplacingallorpartofsteamsystemswhichmaydelivermuchgreatersavings;and,thespecificbusinessbenefitsoftheheatpumpinanapplication.

• Thereisverypoorinformationavailabletomodelmanyoftheseaspects.Ideally,wewouldbeabletoatleastsourcedataonthetemperatureofthermalneedsineachsectorofthefoodindustry,theavailabilityofwasteheatstreamsandtheirtemperature.Thiswouldprovideastartingpointforfurtheranalysisbutthisdataisnotavailable.

• Asaresult,wetookaverysimplisticapproachtoatleastseetheouterlimitsofthepotentialasfollows:

• Scaleofpossibleimpact:

• Foodprocessingconsumes165PJ/yearofenergy(up7%in2016–onlyindustrysectortogrow).41PJisliquidandgasfossilfuel(37PJnaturalgas,1PJLPG,3PGoil),potentiallyreplaceableusingheatpumps(seethetableonenergyconsumptionintheindustrybelow).



EnergyuseintheAustralianfood,beverageandtobaccoindustry2014-15

11-12Food,beveragesandtobaccoFuelsconsumed PJ

Blackcoal 8.3BrownCoal 0.0CrudeOilandOtherRefineryFeedstock 0.2Coalbyproducts

Browncoalbriquettes 0.2Wood,woodwaste 2.8Bagasse 88.4LPG 0.8Autogasoline 0.3Lightingkerosene 0.2ADO 1.4IDF

Fueloil 0.5Petroleumproductsnec 2.4Bitumen

Naturalgas 36.7Towngas

Electricity 22.1Liquid/gas-Biofuels 0.6Derivedfuelsproduced

ThermalelectricitySynthetics–biofuelsEnergyconsumption 164.9

Extractedfrom:OfficeoftheChiefEconomist2016,TableFAustralianenergyconsumption,bystate,byindustry,byfuel,energyunits.Retrievedfromhttps://industry.gov.au/Office-of-the-Chief-Economist/Publications/Pages/Australian-energy-statistics.aspx#

• ArecentreportpreparedbyITPower2forARENAindicatesthatofthe35PJoffuelusedin2012-2013inthefoodindustryoutsidethesugarindustry,some15PJisproducedinthetemperaturerangeupto150oC,andtheremaining20PJabovethistemperature.Thisseemsasurprisinglylowproportion,butitappearsthatthereportbasesitsestimatesonthetemperatureatwhichheatisgeneratedratherthanthetemperaturerequirementoftheprocess.Fornow,let’sassumethatthisistheouterlimitofpotentialheatpumpapplications(escalatedtotoday’susage–sosay18PJ).

• Useofcentralsteamsystemsistypicallyrelativelyinefficient,soreplacementwithdistributedheatpumpswouldreduceenergydemand.

• Mostoftheaboveheatloadcouldbeprovidedbyheatpumps(thoughweaimtoreplacealotofthermalprocesseswithnon-fossil/non-thermalprocesses).

2ITPower2015,RenewableenergyoptionsforAustralianindustrialgasusers,AustralianGovernment,Canberra



• Theeconomicsofheatpumpsissignificantlyimprovedwherewasteheatisavailableattemperaturebelowprocesstemperature–theefficiencyisimprovedbyabout3%foreachdegreereductioninlift.Butthereisnoinformationavailableontheavailabilityofwasteheatineachfoodindustry,sowecannotusethistonarrowthepotentialmarket.Wherewasteheatisnotavailable,orislimited,itmaybefeasibletouserelativelylowcostsolarcollectorsandstoragetoprovideheatat60°Corhigher.

• Ifyoucoulddisplacesay20-25%ofthe18PJoffueldisplacementthiswouldreduceliquid/gasuseby4PJ,(using0.5-0.8PJofelectricity),savingabout1/3ofcarbonemissionsor200KTC02(upto600Ktifpoweredbyrenewables,dependingontheproportionoftimeandenergytherenewableenergysystemcouldprovide).



8 Conclusionsandnextsteps

Conclusions

TheAustralianAllianceforEnergyProductivityhasreachedthefollowingconclusionsasaresultofconductingthisproject:

• Hightemperature(over65oC)industrialheatpumptechnologyhasdevelopedrapidlyinthepastdecade.Therearenowmanycommercialproductsforindustrialprocesses,includingthefoodprocessingindustry.Thousandsofunitsarenowinservice,inJapan,SouthKoreaandEuropetosupplyheatatupto95oC.Thetechnologyhasalsoextendedtodevelopmentofheatpumpsdeliveringsteamatupto150oC.

• TherearebarelyahandfulofhightemperatureindustrialinstallationsinAustralia.Thismeansthatthereareveryfewlocalcaseexamplesofthetechnologybeingsuccessfullydeployed,andthisneedstobeovercometoassistintheacceleratingdeploymentofthistechnology.

• Thelocalsuppliersofheatpumpsarebranchesofglobalcompanies,arequitemotivatedandhaveaccesstointernationaltechnology,thoughthereisnotmuchlocalpracticalexpertiseandexperienceonthegroundgiventhepotentialmarket.Thiscouldbeturnedaroundrapidlyhowever,astherefrigerationindustryhastheskillstorapidlylearnaboutheatpumpsforheatingduties.

• HightemperatureheatpumpscouldplayanimportantroleintheAustralianfoodindustrytorecoverheatanddisplacesteamcurrentlysuppliedfromnaturalgasandLPG.Withtherapidescalationingaspricesandpotentialgassupplyconstraints,andtheneedtomovetolowcarbonenergysolutions(astheelectricityusedinheatpumpscouldbesuppliedfromrenewablesources),hightemperatureheatpumptechnologycouldbeasignificantcontributor,providingsomeofthemanybarrierstoimplementationcanbeovercome.

Recommendednextsteps

ThereisenoughpotentialidentifiedthroughthisprojecttojustifyfurtheractionstopromotetheapplicationofHTheatpumpsintheAustralianfoodindustry,including:

• Partfundandconductatleastfivecaseimplementationsinarangeofidealapplications(andinavarietyofindustries)withsignificantreplicationpotentialtodemonstratethebenefitsofheatpumpsinlocalpractice.Thiswouldbothhavethebenefitofdemonstrationforothersinthesameindustry,butalsobuildlocalcapacityandexperiencewithimplementingHTheatpumpsinAustralia.ARENAand/orNSW/VictoriaStategovernmentagenciesmaybeasuitablesourceforthisfunding.

• Part-fundatleasttwoadditionallargerprojectsdemonstratingthecompletereplacementofboilersandsteamsystemswithpointofenduseheatingapplications,includingheatpumps.Fullydocumentthebusinessbenefitsanddisseminatethisinformation.

• Associatedwiththesecasestudies,runaseriesoftrainingcoursesonheatpumpsandsteamsystemreplacementopportunitiesformanufacturers,andinvolvebusinessassociationsandarangeofstakeholderthatcouldbenefitfromexposuretothisknowledge.



• Designandrunatrainingcourseonpinchanalysis,specificallydesignedtocatertoidentifyingoptimalheatpumpsapplications.

• BuildaformalrelationshipwiththeIEAHeatPumpCentreandtheJapaneseHeatPumpAssociation,andconsiderthebenefitsofestablishingaCentreinAustralia(ideallyatoneoftheStategovernment’sexistingactivitiese.g.NSWOEHorSustainabilityVictoria),topromotethebenefitsofheatpumpsandprovidesupportforsuppliersandusers,andtransferinternationalbestpracticetechnology.

• ConsiderfundingthedevelopmentandapplicationofacomputermodeltosimulateapplicationsofHTheatpumps.Thiscouldbeusedtoscreenpotentialsitesfordemonstrationprojects,potentiallybedoneinpartnershipwithcommercialsuppliersortheIEAHeatPumpCentre.



AppendixA:Heatpumpstakeholdercontributors

Thelistbelowcontainsthenamesoforganisationsandindividualsthatprovidedinputtothisreport.Wethankthemfortheircontribution.

AIRAH–PhilWilkinson

Borgcraft–JamesPapadopolous

CAGroupServices–IanTuena

CraftBeerIndustryAssociation–ChrisMcNamara

ColdLogic–BradSemmler

CSIRO–StephenWhite

DairyIndustryAssociation–IanOlmstead

ECO2Technologies/Minus40–MichaelBellstedt

Emerson–JohnThorne

FonterraAustralia–JackHolden

GoodmanFielder–MickAnderson

JohnsonControl–RicardoHoffmann

KDRCompressors-TonyKitchener

Mayekawa–PeterO’Neill

MeatandLivestockAustralia–DougMcNicholl

MitsubishiHeavyIndustries–TrentMillerandOscarXu

NSWOfficeofEnvironmentandHeritage–DavidMalicki

OakRidgeNationalLaboratory–VanBaxter

Parmalat–MichaelRobinson

PyramidSalt–GavinPrivett

RMITUniversity–AliakbarAkbarzedeh,AbhijitDateandCameronStanley

Simplot–GrahamBryantandScottHall

SheneEstateDistillery–DavidKernke

SustainabilityVictoria–WarrenOverton,KatrinaWoolfe,YolandaSztarrandNickKatsanevakis

TeysAustralia–CarlDuncan

ThomasFoodsInternational–NektaNicolaou



AppendixB:Internationaltechnologyreview

B.1Foodindustrycasestudies

ThomasFoodsInternational,Australia:Heatrecoveryfromrefrigerationplant

In2012aheatpumpwasinstalledattheLobethalAbattoirinSouthAustraliatooffsetgas-firedboileruse.ThetwostageAmmoniaheatpumptakeswasteheatfromrefrigerationplanttoheatwaterto75°C.Theincomingwatertemperatureis11°C.Onceheated,thehotwaterisdeliveredtoathermalstoragetank.Mostofthewaterisusedatnightforcleaningandsterilisingprocesses.Thetankisrefilledduringthedaywhenthereislittledemandforhotwater.

http://www.ampc.com.au/uploads/cgblog/id28/Heat-Recovery-From-Refrigeration-Plant.pdf

Mohrenbrauerei,Austria:Compressionheatpumpreducinggasusageinbrewery

Toreducegasusageassociatedwithitssteamplantandboiler,thebreweryinstalledahightemperatureheatpumpwithaheatingcapacityof370kW,usinganammoniarefrigerant.Theheatpumputiliseswasteheatfromchillersforspaceandprocessheatingandheatingofprocesswaterto77°C.Theheatpumpcost365,000EUR.

Casestudy8.3.2:http://heatpumpingtechnologies.org/publications/application-of-industrial-heat-pumps-part-2/

Agrana,Austria:Dryingstarchfrompotato,wheatandcorn

AustrianfoodproducerAgranaisparticipatinginaEuropeanUnionfundedproject,DryFiciency.Aspartoftheprojectademonstratorheatpumpsystemwillbeinstalledfordryingofstarchfrompotato,wheatandcorn.Starchisdriedusinghotair.Theairisheatedinthreeconsecutivesteps:preheatingbyaheatrecoverycycle(HRC),heatedbywasteheatfromanotherdryer;heatingbysteamcondensate;andheatingbysteam.TogainmoreenergyfromtheHRC,thedemonstratorheatpumpunitwillbeinstalled.Theusefulsupplytemperatureoftheheatpumpsystemwillbefrom130to160°Candtheheatingcapacitywillbeapproximately600kW.

http://dry-f.eu/Demonstrations/Agrana-Food-industry

McCainFoods,TheNetherlands:DryingFrenchfriesbeforetheyarebaked

Abeltdryerthatoperatesatamaximumtemperatureof70°CisusedtodryFrenchfriesbeforetheyarebaked.TheheatpumpusesAmmoniaasitsrefrigerantandisdesignedtocondensate1,500kgofwaterperhour.Tworeciprocatingcompressorsareused;aGrasso45HPandaGrasso65HP.Thesecompressorshaveacontinuouscapacitycontrol.TheirCOPinthisprocessdependsonthedryingconditionsandvariesbetween5to8.Savingsupto70%onthedryer’senergyconsumptionareachievable.

http://www.industrialheatpumps.nl/en/practices/heat_pump_for_drying_of_fries/

Nortura,Norway:Hybridheatpumptoheatwaterforcleaninginslaughterhouse

Theheatpumpinstallationuseswaterandammonia.Thesourceofwasteheathasatemperatureof49°Cwhichisupgradedbythehybridheatpumpto88-90°C.Itisusedtoheatwaterforcleaningandsterilization.TheinstallationhasaCOPof5.2.Annualenergysavingsof13.700GJor



500,000litresoffueloilarerealized.

Ahybridheatpumpusestheprinciplesofoperationofbothamechanicalandanabsorptionheatpump.Temperaturesashighas130°Ccanbereachedwithrelativelylowsystempressure.Therefore,standardcomponentscanbeused.TheNorwegianInstituteforEnergyTechnologydevelopedthehybridheatpumptechnology.

http://www.industrialheatpumps.nl/en/practices/hybrid_heat_pump_at_slaughterhouse/

DairyCooperativeTine,Norway:Heatrecoveryforhotwatergeneration

Theheatrecoverysystemutiliseswasteheatfromthedairy’srefrigerationsystemtofulfilthedairy’sdemandforCIPwaterat73°C(COP5.8).Thesystemisalsoconnectedtoalocalheatingnetworkwhichsuppliesheattonearbygreenhousesat58°C(COP9.0).ThesystemusesanAmmoniarefrigerant.

Casestudy7.5:http://heatpumpingtechnologies.org/publications/application-of-industrial-heat-pumps-part-2/

Slaughterhouse,Switzerland:800kWheatpumpsystemforhotwatergenerationandheating

The800kWsystemismadeupof3carbondioxiderefrigerantheatpumpsthatdeliverwaterupto90°C.Theheatedwaterisusedforslaughteringandcleaningpurposesandforfeedwaterforasteamgeneratorandtheheatingsystem.TheheatpumpsystemuseswasteheatfromanexistingAmmoniarefrigerationmachine,anoilcooledaircompressorplantandfan-coilunits.TheCOPoftheheatpumpis3.4.


Nestle,UK:Heatingandcoolinginchocolatemanufacturingprocess

NestleinstalledacombinedheatingandcoolingsystemusingammoniaheatpumpsinitsHalifaxchocolatemanufacturingfacility.Heatingcapacityofthesystemisprovidedby2x600kWunitsandcoolingcapacityby2x1600kWunits.Heatissourcedfromtheglycolcoolingprocessandresultsinprocesswaterbeingheatedfrom10°Cto60°Cinonestep.Theplantrequiresasmallamountofwaterat90°C.Theincrementalheatissuppliedbyasmallgasboilerheatingthewaterfrom60°Cto90°C.ThecombinedheatingandcoolingCOPis6.25.Inadditiontoreducingenergycostsandcarbonemissions,installationoftheheatpumpsystemhasalsoresultedinasignificantreductioninwaterconsumption.


HakutsuruSakeBrewingCompany,Japan:heatrecoverytoproducehotandcoldwater

In2012theNadauozakifactoryofHakutsuruSakeBrewingCowasconstructedwithenergyefficiencyandenvironmentalsustainabilityinmind.Thesakeproductionprocessrequiresbothheatingandcoolingenergy.Theheatingandcoolingloadssitsidebyside,allowingtheveryefficientutilisationofaCO2heatrecoveryheatpumpthatsimultaneouslyproduceshotandcoldwater.Theexhaustheatgeneratedwhenproducingcoldwaterisusedproducehotwater.The



heatpumpsystemhasachievedaCOPof5.7.

http://www.hptcj.or.jp/e/publication/tabid/790/Default.aspx

Frozennoodleproduction,Japan:Simultaneoushotandcoldwaterproduction

Productionoffrozennoodlesrequireshotwaterat80°Corhigherinthenoodleboilingprocessthencoldwaterataround5°Cinthecoolingprocessbeforefreezing.Thenoodlecompanyinstalledaheatpumptoproducebothhotandcoldwater.Theheatpumpproduceshotwaterat90°C,whichisstoredinahotwatertankuntilrequired.Mostofthehotwaterisusedtofillboilingpoolsatthestartofproductioninthemorningtoreducethepeakloadofthesteamboilers.Coldwaterat5°Cissuppliedbytheheatpumpandusedtocoolthewaterintherawwatertank(17°C)toreducetherefrigerationload.TheheatpumphasatotalCOPforsimultaneoussupplyof5.1(3.0forheatingand2.1forcooling).


SungrainLtd,Japan:Combinedvapourre-compressionsystemforalcoholdistillation

Acombinedthermalvapourre-compression(TVR)andmechanicalvapourre-compression(MVR)systemwasdevelopedtoreducethere-compressionpowerrequiredforlow-pressuresteamrecycledforheatingoftheethanolrectifyingtower.TheTVRcompressesvapouratacompressionratioof1.7,thentheMVRcompressesvapourat2.1.Installationofthecombinedvapourre-compressionsystemresultedina43%reductioninprimaryenergyconsumptionfortherectifyingandmethyltowers.


Poultryprocessing,US:Scaldingandfeatherremoval

Toremovefeathersandscaldchickencarcassskin,waterat60°CisrequiredinacontinuousprocessataTexanpoultryprocessingfacility.Thesameprocessalsorequiressignificantcoolingwhichprovidesthesourceofheatfortheheatpump.Enteringwatertemperatureisapproximately20°C.AsimplesinglestageheatpumpachievesaCOPof7.0(comparedtogasboilersystemCOPof0.83).Thesystemdelivers56,603MMBTUofheatannuallyandcostUS$750,000.

http://www.emersonclimate.com/Documents/Vilter/Product_Brochures/White_Paper_2011ECT-27_C.pdf

Beefprocessing,US:Hotwaterforequipmentsanitation

AbeefprocessingfacilityinTennesseehassignificantcoldstorageandfreezingloadsthatprovideasourceofheatforitsheatpumpsystemthatproduceshotwaterforsanitationpurposes.However,sanitationtakesplacebetweenprocessingshiftswhenrefrigerationdemandisataminimumordiminishingsoastoragetankisusedtobuildupthehotwatersupplythroughouttheday.Theenteringwatertemperatureis15°Candtheleavingwatertemperatureis70°C.ThecapitalinvestmentwasUS$800,000foraheatpumpsystemthatdelivers64,287MMBTUofheatperyear.TheheatpumpsystemCOPis5.9(comparedtogasboilersystemCOPof0.96).




Dairyprocessing,US:Hightemperatureshorttime(HTST)pasteurisation

TheHTSTpasteurisationprocessinthisWisconsindairyfactoryutilisesanefficienttwostageheatpumptodeliverthe90°Cwatertemperaturerequired.Enteringwatertemperatureis10°Candrefrigerationistheheatsource.ThetwostageheatpumpsystemcostUS$1,250,000anddelivers60,507MMBTUofheatperyear.TheheatpumpsystemhasaCOPof4.2(comparedtogasboilersystemCOPof0.85).


Poultryprocessing,Canada:Cascadedheatpumpsystem

Thefirststageofthecascadedheatpumpsystemusedinthispoultryprocessingplantrecoverswasteheatfromanindustrialicemachine.Coldwaterentersthesystemat12°Candisheatedto25°Cinthepre-heatingheatexchanger,thenheatedupto63°Cwiththecascadeheatpumppriortobeingstoredinastoragetankand/orsuppliedtoindustrialprocesses.ThetotalinvestmentcostofthisheatrecoverysystemwasUS$165,000andthesystemoverallCOPhasbeenestimatedat10.7.


B.2Researchanddevelopment

TocircleIndustries,Norway:DevelopmentofhightemperatureheatpumpfortheEuropeanfoodandbeveragemarket

TocircleIndustriesofNorwayandDuynieHoldingsoftheNetherlandshaveestablishedajointventureforproductionandsalesofindustrialheatpumpsystems,withfirstdeliveriesscheduledforQ32018.Theheatpumpsincludeatwostagecompressorassembly,eachconsistingoffourcompressors.Theheatpumpswillbeusedforupgradingresidualheatrecoveredinheatintensivefoodmanufacturing.

http://www.tocircle.com/commercial-breakthrough-tocircle-industries/

DeKleijnEnergyConsultants,TheNetherlands:Pasteurisationwithanaddonheatpump

Forpasteurizationaproductneedstobeheatedabove70°C.Afterwardstheproductiscooleddown.Theproducttemperaturethusvariesfromcoldbeforepasteurizationtohotduringpasteurizationandbacktocoldagainafterpasteurization.Applicationofanadd-onheatpumpenablesreuseofthewasteheatfromthemechanicalcoolingsysteminthepasteurizationprocess.Iftheadd-onheatpumpisapplied,noadditionalsteamisneededforthepasteurizationprocess.

http://www.industrialheatpumps.nl/en/applications/

ECN,TheNetherlands:Developmentofheatpumpthatuseswasteheatorgeothermalheattogeneratesteamupto200°C



TheSTEPSprojectwilldevelopandtesttwoadvancedheatpumpconcepts:amultistagereverseRankinesystemandasinglestagethermoacousticsystem.Thermoacousticsreferstothephysicalphenomenonthatatemperaturedifferencecancreateandamplifyasoundwaveandviceversa,henceasoundwaveisabletocreateatemperaturedifference.Thisenablesthedevelopmentofasystemwithnomovingpartsthatcanoperateunderawiderangeoftemperatures.

https://www.ecn.nl/news/item/high-temperature-heat-pump-technology-for-sustainable-steam-production-in-industry/

KobeSteel,Japan:Air-sourced90°Chotwatersupplyingheatpump

Thisheatpumpiscapableofsupplyinghotwaterat65-90°Ctotheheatingprocessoffactoriesmakingproductssuchasfood,beverages,automobilesandchemicals.Thenewlydevelopedheatpumphasachievedveryhighenergyefficiencyforsupplyinghotwaterbycirculationheating.Thiswasmadepossiblebyusingatwo-stagetwin-screwcompressormodifiedforhightemperatureoperationbyselectinganadequaterefrigerantandoptimisinganair-sourcedevaporatorunit.

http://www.kobelco.co.jp/english/ktr/pdf/ktr_32/070-074.pdf

IEAHeatPumpCentre,International:Industrialheatpumpprojects

HeatPumpCentreprojects“Annex35”and“Annex48”lookedatheatpumpswiththeabilitytoproducedheatatupto200°Cwhichcanbeusedforheatrecoveryandheatupgradinginindustrialprocesses,andalsoforheating,coolingandair-conditioningincommercialandindustrialbuildings.

http://heatpumpingtechnologies.org/

IEAHeatPumpCentre,International:Heatpumpsinsmartgrids

HeatPumpCentreproject“Annex42”examineduseofheatpumpsasatoolfordemandmanagementinsmartgrids.Smartheatpumps,withtheabilitytocommunicatewiththegrid,canbeusedasabridgebetweenpowerandheating,convertingrenewablepowertoheat,whichcanbestored.

HPTMagazine,p.19https://issuu.com/hptmagazine/docs/hpt_magazine_no1_2017?e=24860023/46502186

Otherreferences:

FischerD.,MadaniH.Onheatpumpsinsmartgrids:Areview,RenewableandSustainableEnergyReviews70,342(2017).

Dallmer-Zerbe,K.,Fischer,D.,Biener,W.,Wille-Haussmann,B.,&Wittwer,C.Droop,ControlledOperationofHeatPumpsonClusteredDistributionGridswithHighPVPenetration.InIEEEEnergycon.inproceedings,Leuven(2016).

HeatPump&ThermalStorageTechnologyCentreofJapan:Surveyofavailabilityofheatpumpsinthefoodandbeveragefields

Reportexaminingreplacingsteamboilers(endusetemperaturebelow100°C)withheatpumpsInthefoodandbeverageindustriesof11counties.ThereportfoundsignificantenergyconsumptionandCO2reductionswereachievablebydeployingheatpumptechnologiesinthefoodand



beverageindustry.Inmostcaseselectricdrivecompressionheatpumpswereutilised,withtheexceptionofmechanicalvapourrecompressionusedinthebeerbrewingindustry.

http://www.hptcj.or.jp/Portals/0/data0/e/publication/pdf/survey.pdf

CentreofAppliedMathematicsMinesParisTech,France:Heatrecoverywithheatpumpsinthefoodanddrinkindustry

Adetailedbottomupenergymodelwasusedtoanalysetheimpactofheatrecoverywithheatpumpsonindustrialprocessesupto2020onenergysavingsandCO2emissionreductionsintheFrenchfoodanddrinkindustry.Theresultsshowedheatpumpscouldbeanexcellentenergyrecoverytechnology.

http://www.sciencedirect.com/science/article/pii/S0306261913004364



AppendixC:CoefficientofperformancebackgroundInformation

Theefficiencyofrefrigerationsystemsandheatpumpsisdenotedbyitscoefficientofperformance(COP).TheCOPistheratiobetweenenergyusageofthecompressorandtheamountofusefulcoolingattheevaporator(forarefrigerationinstallation)orusefulheatextractedfromthecondenser(foraheatpump).Mostoftheelectricenergyneededtodrivethecompressorisreleasedtotherefrigerantasheat,somoreheatisavailableatthecondenserthanisextractedattheevaporatoroftheheatpump.ForaheatpumpaCOPvalueof4meansthattheadditionof1kWofelectricenergyisusedtoachieveareleaseof4kWofheatatthecondenser.Attheevaporatorside3.0-3.5kWofheatisextractedandadditionalheatfromtheelectricityinputtorunthemotor/compressorisadded,sothatatotalof4unitsofheatisdeliveredwhenonly1unitofelectricity(ormechanicalenergy)isused.ForarefrigerationsystemaCOPof4indicatesthat1kWofelectricityisneededforaevaporatortoextract4kWofheat.DuetothisimportantdifferenceinCOPdefinition,foraheatpumponeoftenspeaksofCOPh.

Figure28–Coefficientofperformanceforheatingforammoniarefrigerant

Theefficiencyofaheatpump,COPh,dependsonseveralfactors,especiallythetemperaturedifferencebetweenwasteheatsourceandpotentialheatrequirement(?).Thetemperaturedifferencebetweencondensationandevaporationtemperaturelargelydeterminestheefficiency:thesmallerthedifference,thehighertheCOPh.ThefigureaboveshowstheinfluenceofthistemperaturedifferenceontheCOPhvalue.ThesevaluesarebasedonfiguresfromacompressorusingAmmoniarefrigerant.



AppendixD:Hightemperatureheatpumpswithnaturalrefrigerants

AndyPearson,UK

Introduction

Theeconomic,commercialandtechnicalconditionsnowseemtobeinteractinginsuchawayastomake the recovery of heat from buildings and process outputs, or even from their surroundings,compellinglyattractive,likeneverbefore.

Someof the technical requirementsarequitedemanding.Refrigerantswhichdonot interactwiththeozonelayerorotheraspectsoftheglobalclimate,yetofferahighefficiencyfromcompactandrelatively inexpensiveplant, arenowhighlydesirable. Inmany cases requiringmajor investments,theenvironmentalaspectsofthespecificationareaprerequisiteforgettingtheproject funded. Inothers, particularly for private “blue-chip” clients, there may be corporate social responsibilityguidelinestomeet,whichprecludetheuseoffluorinatedrefrigerantsunlessstrictlynecessary.Thisperceptionisparticularlyimportantinlargesystems.Forexampleasystemwitha10000kgchargeofR-134awhichleaks2%ofthechargeperyearhasaclimateeffectthatisequivalenttodrivingafamilysaloonmorethan50000kmperweek.

With these constraints the list of possible refrigerants and systems is very short. Five substancesofferthemostpromiseasworkingfluidsinindustrialheatingapplications:water,air,hydrocarbon,ammonia and carbon dioxide. The optimal configuration of operating system varies widely de-pending on the class of fluid, but they all fall within the general description of thermodynamicsystemsinwhichheatisaddedtoafluidbycoolingthesurroundingsandthenworkisperformedonthefluidtoraiseittoahigherpressure,atwhichpointtheheatinputandtheworkinputcanjointlybeextractedandusefullyappliedtoaprocess,productorsituationwhichrequirestobeheated.Insome of these systems, notably with water, hydrocarbon and ammonia, the working fluid isevaporated and recondensed in a Perkins cycle. The air system, however, works by heating andcooling the gas without any change of phase. In the special case of carbon dioxide the heatextractionisaccomplishedbyphasechangebuttheheatdeliveryisatapressureabovethecriticalpointandthereforethereisnochangeofphaseasthegasiscooled.

Water

Systemsusingwaterasaworkingfluidoperateatverylowpressures–theboilingpointofwateratatmosphericpressureatsealevelis100°C,soformostindustrialheatpumpstheentirecircuitwouldbeatsub-atmosphericpressure.Thelatentheatofwaterisalsoveryhigh,aboutfifteentimesthatofR-134aat50°C.Thesepropertiesraisetheprospectofdeliveringhightemperatures,say150°C,atmodestpressurescomparedtoallotherworkingfluidchoices,butsomeoftheotherpropertiesofwatermakethisachallengingproposition.Thesweptvolumerequiredisextremelyhigh,duetothelowdensityofwatervapour,andthepressureratiorequiredisalsoquitehigh,duetothelowinletpressure. Forexample to raiseheat from50°C to150°Cwould require thedischargeof thewatervapoursystemtobebetween4and5bargaugebuttheinletwouldbeatabout0.1barabsolute,sothepressureratio isbetween50and60.Sincewater isarelativelysimplemoleculethe isentropic



index is quite high, at approximately 1.3 at these conditions. This makes water quite similar toammoniainthisrespect,butanammoniasystemoperatingatthesepressureswouldevaporateat–71°C and condense at 4°C. Therefore, in order to keep the discharge temperature down to atolerablelevel,manystagesofcompressionarerequired,withinter-stagecoolingbetweenthem.

Air

TheoriginalconceptoftheheatpumpproposedbyLordKelvinin1852wasofanaircyclemachine(IEA Heat Pump Centre Newsletter Volume 30 - No. 1/2012 www.heatpumpcentre.org) withcompression and expansion cylinders on a common drive shaft burning coal to raise ambient airtemperatures sufficiently to heat houses with the discharge air from the compressor. Kelvincalculated that thecoefficientofperformanceof suchasystemwouldbe35:1basedon theshaftpower when operating between temperatures of 10°C and 27°C, and since a “very good steamengine”convertedabout10%oftheheatofcombustionofthecoalinitsfurnacetoshaftpower,heconcludedthatsuchadevicewoulddeliver3.5timesmoreheatthancouldbeachievedbyburningthesameamountofcoalinadirectprocess.Headdedthatifawaterwheelwereusedtodrivethecompressor and expander the economy would be even more attractive. In Kelvin’s preferredarrangementofthisapparatusthesystemcouldbeusedforheatingorcooling.Thesystemhadtwocylindersofequalsize,onepassingairfromtheoutdoorambienttoalarge,thin-walledreceiverandtheseconddrawingair fromthe receiveranddelivering it to theoccupiedspace.A third, smaller,auxiliarycylinderwasusedtodeterminewhetherthesystemactedasaheatingorcoolingdevice.Ifitpressurisedtheairinthereceiver,causingthemaininletcylindertodoworkontheinletair,thenthe receiver would be heated and would lose heat to the surroundings. In this case the outletcylinder would act as an expander, cooling the air as it brought it back down to atmosphericpressure.Iftheauxiliarycylinderdrewairfromthereceiveranddeliveredittothedestinationspacethenthereceiverwouldbebelowatmosphericpressureandwoulddrawheatfromitssurroundings.The inletcylinderwouldbeanexpanderandtheoutletwouldbethecompressor,bringingtheairbackuptonormalpressurebutathighertemperature.Kelvincalculatedthattodeliverairat27°Cwhentheoutsidetemperaturewas10°Cwouldrequirethereceivertobeheldat0.82barabsolute.InamodernversionofKelvin’ssystemthereceiverwouldbereplacedbyafinnedheatexchangerand the compressor/expander device would probably be a turbocharger with a small screw orreciprocatingcompressorreplacingtheauxiliarycylinder.

Kelvin’ssystemcouldbedescribedas“closed-open”.Inotherwordstheheatextractionisthroughaheatexchanger(thethin-walledreceiver)andtheheatdeliveryisbydirectpassageoftheairfromthe system to the occupied space. This is similar to the concept used for train air-conditioners,wherethesystemdrawsoutsideairthroughanexpanderandaheatexchanger,thencompressesittoreturnittoatmosphere.Thesesystemsneedtooperatebelowatmosphericpressureinordertoachieve the cooling and heating effects. Most modern air cycle systems, in contrast, are “open-closed” or in some cases “closed-closed”. When the heat delivery process is through a heat ex-changer,or“closed”, thentheairwillbecooledduringthedeliveryofheat.Suchasystemisbestsuited to heating through a wide temperature range because there is no phase change in theworkingfluid.Tomaximiseefficiencytheheatexchangermustbedesignedforcounter-currentflow,withtheinlet(hot)airincontactwiththeoutlet(heated)processfluidandtheoutlet(cooled)airincontactwiththe inlet (cold)processfluid. Ifacrossfloworco-currentheatexchanger isusedthentheoperatingtemperaturesneedtobemuchfurtherapartthanforthecounter-currentsystemandso the temperature lift ishigherand theefficiency is farpoorer. Ifhighprocess temperaturesarerequiredthenthekeydesignchallengeistomakeacost-effectivecounter-currentheatexchanger.



Hydrocarbon

Thefamilyofshort-chainhydrocarbonsoffersseveralfluidswithfavourablepropertiesforhightem-perature heat pump systems. Butane and isobutane (methyl propane) are particularly attractivebecause they have high critical temperatures of 136°C and 151°C respectively and so can heat toextremelyhigh temperatures if required.However theoperatingpressuresaremoderate, evenathightemperatures,andthereforeequipmentisreadilyavailable.Forexampletocondenseat110°Cthedischarge from the compressor forbutaneand isobutanewouldbe17.3bar g and23.1bar grespectively; not significantly different from the discharge pressures of R-22 and R-404A systems.Howeversystemapplicationisconstrainedbysafetyrequirementsduetoflammability.Thequantityofworking fluid in thesystem,alsocalledtherefrigerantcharge, isusedtodeterminepermissiblelocations. If the system is designed under the jurisdiction of EN 378, the European Standard onrefrigerationsafety, thenthechargeof thesystem is limited to150g if it is installed ina locationaccessibletothegeneralpublic,suchasaschool,asupermarketorahospital,withsomerelaxationforlargespaceswherethechargecoulddissipatesafelyintheeventofaleak.Howeverthereisanabsoluteupperlimitof1.5kgcharge.Insupervisedoccupancies,suchasofficesandlaboratories,theupper limit of charge is 2.5 kg. It isworth noting that the lowmolecularweight of hydrocarbonsmeans that their liquiddensity isalsocomparatively low. It is thereforepossible,ona like-for-likebasis, toachieveahigherheatingcapacity fromagivenweightof refrigerantcharge.Forexamplemethylpropaneisonly60%ofthemolecularweightofR-134aanditsliquiddensityat20°Cisonly46%ofthatofR-134a.Withpropanetheratiosareevenlower,at44%and41%respectively.

For industrial systems it would be feasible to use much larger hydrocarbon systems with norestriction on charge but the equipment must be installed in a machinery room or outside thebuildingintheopenair,andstrictprecautionsagainstexplosionsintheeventofaleakarerequired.The charge in these systems can be minimised by using plate-type or plate and shell heatexchangers, but will probably still be larger than the practical limit for a typical sizedmachineryroomduetothelowvalueofthelowerflammablelimitofthehydrocarbons.Thesafetyprecautionsincludegasdetection,ventilationandemergencylightingwhichmustallberatedforoperationinaflammableatmosphere,forexampleasflameproof(Exd)orincreasedsafety(Exe).Itisnotnormallynecessary for the heat pump to be certified in thisway unless it is intended to operatewithin aflammableatmosphere,although itwill alwaysbe subject toahazardassessment in linewith theATEXdirective.

Components are generally widely available for use with hydrocarbons, although in some casesspecial certification is required. Compatibility of seals and O-rings should be checked, and thelubrication system may require special care because hydrocarbons are highly soluble in mostlubricants.Apart fromtheseminorconsiderationsthehydrocarbons,especiallybutaneandmethylpropane, are relatively easy to work with, and have low discharge temperatures even over highpressureratios.

Ammonia

Heat pumps with ammonia operate at relatively high pressures compared to almost all otheroptions. However, as a result of ammonia’s high critical temperature, it is possible to achieveexcellentefficiencyinhigh-temperaturesystems.Watercanbeheatedto90°Ctakingheatfromanambientsourceat8°Cwithacoefficientofperformanceof3.2andifthesourceisfromwasteheatathighertemperaturesthentheefficiency isofcoursealsomuchhigher.Athightemperatureandpressure there are some significant challenges to overcome. Refrigerant solubility in lubricant



increases, so that the viscosity of the lubricant fed to the compressor is extremely low. Sealmaterialswhichareacceptableatlowertemperaturesandpressurestendtoshrinkandharden,soalternativematerialsarerequired.Theresinsused inoil filtersandcoalescersarealsoaffectedbythehighpressureandtemperaturewhichcanshortenthefilterlifeandpossiblyleadtofailureofthefilterelement.Althoughtheoperatingpressuresarehightheratioofdischargetosuctionpressureisactually very low, so there are some additional challengeswith screw compressors in getting theright volume ratio and keeping the compressor at optimal efficiency. Internal forces within thecompressorarehighduetothehighpressuredifferencebetweendischargeandsuction.Vibrationlevelsalsotendtobehighbecauseofthehighdensityofthedischargegas.

Allofthesechallengeshavebeenovercome,insomecasesbyselectionofalternativematerialsandin others by redesign of the system components to ensure that the equipment is efficient andreliable.Compressorsratedfor75baronthedischargesidearenowavailable,whichinprinciplewillallowheating toabout100°Cwithallowances forhigh-pressure safety switchand relief valve set-tings.

Small to medium-sized heat pumps have also been developed for heat recovery applications,combiningthebenefitsofammoniaandwater.Thesesystemsuseanammonia/watermixture likeanabsorption chiller, butwitha compressor to raise thegas tohighpressure. Theygivegoodef-ficiency at lower operating pressures than the ammonia systems, and can heat to 115°C, but itshouldbenoted thatboth theheatextract and theheatdeliveryexchangersoperatewitha verywidetemperatureglideontherefrigerantside,asthecompositionoftheammonia/watermixturechanges.This requiresa specialdesignofheatexchanger toensurecounterflowheatexchange. Italsomakesthemachinesunsuitableforuseinwaterchillingapplicationsduetotheriskoffreezing.These systems are therefore best suited to applications with high heat source temperaturesoperatingacrossawidetemperaturerange,andapplicationsheatingfluidthroughawiderange.

Carbondioxide

Carbondioxideheatpumpsareverycommoninsmallersizes,buthavenotbeencommercialisedinthelargerrangeduetothelack(todate)ofasuitablecompressor.Liketheammonia/waterhybrid,theyoperatewithawidetemperatureglideonthehighpressureside,butthelowpressuresideislikea traditionalevaporatorwithphasechangeataconstanttemperature.Operatingpressuresof90to100bararerequired,socompressorsneedtoberatedforabout120bar.Inthesmallersizesthishasbeenthefastestgrowingsegmentof themarketandunitsupto100kWheatingcapacityare now available. There have been no major technical barriers to the implementation of thesesystems, and no particular issueswith availability ofmaterials or components. Small systems areavailableforbothair-sourceandwater-sourceheatpumps.

Reproducedwithpermission

Authorcontactinformation:

AndyPearsonStarRefrigerationLtdGlasgow,[email protected]



AppendixE:Pinchanalysis

Reproducedwithpermissionfrom:http://www.industrialheatpumps.nl/en/applications/pinch_analysis/

Pinchanalysisisatoolthatcanbeusedtoanalyseasetofheatflowsandtodeterminewhetheritispossible to interchange these heat flows. When application of a heat pump is considered in acomplexapplication, it isusefultocarryoutapinchanalysis.Thegoal istomapallheatflowsandthen connect hot and cold flows that can exchange heat. Furthermore, the analysis shows theamountofcoolingandheatingneeded.Aheatpumpcanbeusedtocoupletheseneedsforcoolingandheating.

Procedure

Thepinchanalysisisastructuredmethodthatinvolvesthefollowingsteps:

1. Mapallprocessstreamsinsideandinthevicinityoftheplantandcomposeamassandenergybalance.

2. Put the different process streams in a table that shows their supply temperature, desiredtemperatureandheatcapacity.

3. Determine the power of the different process streams for different temperature steps andmakeagraphicalrepresentationofthesedatapoints.

4. Find outwhether or not it is possible to interchange heat betweendifferent process flowswiththeuseofheatexchangers.

5. Determine the locationof thepinchpointand findout ifmoreexchangeofheat isneededafterdirectheatexchangeisperformed.

6. Depending on the temperature levels and powers a decision can be made on whichinstallationismostsuitabletoapply.

Example

Thedifferentstepsofapinchanalysesareexplainedinmoredetailintheexamplethatisstatedbelow.

1. Mapallprocessstreamsinsideandinthevicinityoftheindustrialplantandcomposeamassandenergybalance: Theexampleisbasedonfourprocessstreams.Twostreamsthatneedtobecooleddownandtwostreamsthatneedtobeheated.



2. Put the different process streams in a table that shows their supply temperature, desiredtemperatureandheatcapacity:

3. Determine the power of the different process streams for different temperature steps andmakeagraphicalrepresentationofthesedatapoints.Onthex-axisthepower(eitherheatingorcooling)isshownandthey-axisshowstemperature.Twographs,onecoldstreamandonehot stream, are combined in to one graph:

4. Byinterchangingenergyfromthecoldandhotstreamwiththeuseofaheatexchanger,241kW of heat can be recovered. Ideally above the pinch point asmuch a 186 kW of heat isneededwhilebelowthepinchpoint238kWofcoolingisneeded.

5. The pinch point is determined by the location where temperature differences (delta T)between process streams are the smallest. At this point heat exchangers can operate atminimal delta T. For an increase in delta T at the pinch point due to a change in processtemperatures, specifications for heat exchangers change. Through combining the graphs ofthe two product flows, a joint curve is created that gives insight in process streams andtemperaturevariations.Atthepinchpointatemperaturedifferenceof0°Ciskept.Inpracticeatemperaturedifferenceisneededtobeabletohaveheatexchange.

6. Depending on the temperature levels and powers a decision can be made on whichinstallationismostsuitabletoapply:Forsmalltemperaturedifferenceandaneedforheatingandcoolingthatiscomparable,aheatpumpmightbeinterestingtoapply.Withtheuseofaheatpumpthecoldandhotprocessstreamscanbecoupled.Inthiscaseaheatpumpcanbe



installed that has an evaporation temperature of 25°C and a condensation temperature of82°C.Theremainderisanadditionalcoolingcapacityof50kW.Foratemperaturedifferencethat is too big, efficiency of the heat pumpwill drop to a non-feasible level inwhich casealternative heating and cooling system have to be installed. Examples of these alternativeinstallationsarecoolingtowers,refrigerationinstallationsandhotwaterorsteamsystems.

AustralianAllianceforEnergyProductivityLevel11,Building10235JonesStreet,Ultimo,NSW2007email:[email protected]:+61295144948web:www.a2ep.org.au,www.2xep.org.auabn:39137603993