medical imageing equipment energy use- ccghc 2017 · the high energy consuming medical imaging...
TRANSCRIPT
1
2
TheAuthorsThisreportwaswrittenbytheCanadianCoalitionforGreenHealthCareteam:
• J.J.Knott,CET,CCHFM,CEM,CDSM;andLead-HealthcareEnergyLeadersOntario(HELO)
• LindaVarangu,B.Sc.,M.Eng.• KentWaddington,B.A.,M.A.• Dr.TonyEasty,Medicalimagingtechnicalexpert,providedinvaluable
contributionsguidingthecourseofthisproject.• ShawnShi,EnergyAnalyst,providedassistancewithdataanalysis.
AcknowledgementsTheauthorswouldliketothankNaturalResourcesCanada(NRCan)andBCHydrofortheirfinancialsupportofthisproject.StaffattheUSEPAinterestedinexaminingopportunitiestodevelopENERGYSTAR(R)certificationformedicalimagingequipmentprovidedhelpfulguidance.Weareveryappreciativefortheparticipationofthreehospitalsthatpartneredwithusonthisproject.Energymeasurementsweretakenbyauthorizedtechnicalstaffineachofourpartneringhospitals,supportedbyaninternalteamofexperts.Keyhospitalpartnersandtheirstaffwhocontributedtothisprojectwere:
• NanaimoRegionalGeneralHospital(NRGH),IslandHealth(VIHA),inBritishColumbia
o DeannaFourt(Director,EnergyEfficiencyandConservation)o RobertFulcher(LeaderofMedicalImaging,NRGH)o TedMacLaggen(Manager,BiomedicalEngineering)o LeeMcIntyre(Technician)o BjornRicht(EnergySpecialist,EnergyEfficiencyandConservation)
• TheHospitalforSickChildren(SickKids)inOntario
o AlbertAziza(SeniorManager,IGTandMRI,DiagnosticImaging)o MikeFagan(EnergyManager)o MannyMercado(Electrician)o ElisabethPerlikowski(EnergyandEnvironmentProgramManager)
• UniversityHealthNetwork(UHN)inOntario
o ChadBerndt(EnergyManager)o MichaelKurz(EnergyManager)o MurrayRice(Manager,ClinicalEngineering)o EdRubinstein(Director,EnvironmentalCompliance,Energyand
Sustainability)
3
ThanksalsotoTorontoHydrowholoanedustheirpowerloggertohelpundertakeenergyconsumptionmeasurementsofthemedicalimagingequipmentinToronto.
4
ExecutiveSummaryThepurposeofthisprojectwastoobtainenergyconsumptiondatafromhospitalmedicalimagingequipment(MIE)whichwouldassistgovernmentsponsorsoftheENERGYSTAR®programdetermineifanewcategoryofENERGYSTARproductsshouldbedevelopedforMIE.Partneringhospitals,aswellasBCHydro,whichwasoneofourfunders,alsowantedtogainabetterunderstandingofMIEenergyconsumptionathospitalssothatstrategiescouldbedevelopedtohelpreduceenergyconsumptionandcosts.Threehospitalpartnerstookpartinthisproject:
• NanaimoRegionalGeneralHospital(NRGH),IslandHealth(VIHA),inBritishColumbia;
• TheHospitalforSickChildren(SickKids)inOntario;and• UniversityHealthNetwork(UHN)inOntario.
EnergyconsumptiondatawereobtainedfromthreetypesofMIE:
1. ComputedTomography(CT)2. GeneralRadiography(X-ray)3. MagneticResonanceImaging(MRI)
Eight(8)testingeventswereundertakenwith100sofdatapointsprovidingenergyconsumptiondataforlowpowerenergymodes,standby/idlepowermodeandactive/scanningenergymodes.TheMIEweremeasuredmostlyoverperiodsrangingfromthree(3)daysto11days.Longermeasurementperiodsallowedricherinformationaboutwhenandhowfrequentlytheequipmentwasusedandenabledthecalculationofestimatedannualenergyconsumptionandenergycosts.Extendedmeasurementperiodsalsoprovidedinsightsintoenergyreductionstrategiesthatwouldnotbeavailablethroughtheoriginaltestingprotocol.Theoriginaltestingprotocolreliedon12testingeventseachprovidingthreedatapointswhichwouldhaveresultedinatotalofonly36datapoints.Recommendationsincludethefollowing:
1) DevelopmentofENERGYSTARspecificationforMIEs.a. Thisreportidentifiedthattherearesignificantdifferencesinthelow
powerandscanningpowermodeswithintheequipmentmeasuredandintheenergyconsumptionvaluesreportedliterature.
b. AlongwiththedirectenergyuseofMIE,ancillaryenergyconsumptionofallrelatedancillaryequipmentaccompanyingtheMIEshouldalsobeassessedforreductionofenergyuse.
c. ENERGYSTARspecificationdevelopmentisnotaquickprocess,requiringgovernmentleadership,andmaytakeseveralyearstocomplete.TherearehoweverotheroptionstohelpencouragereductionofMIEenergyconsumptionthatcouldbeactedonmorequicklyandincludethefollowing:
5
2) ProvisionofpurchasingguidelinesforMIEwhichincludeenergyaspectsa. Includingenergyaspectsinpurchasingdecisionsisnotcurrentlypart
ofthepurchasingpracticesinCanadianhospitals.Convincingpurchaserstoincludeenergycriteriawouldrequireeducation,guidanceandprovisionofsolidbusinesscaseinformationforthedecisionmakers.
b. TheGreenPublicProcurement(GPP)initiativepromotedinEuropeestimatespossibleenergysavingsof50%forMRIandCT,and80%forX-rays.
3) DevelopenergybehaviourguidancedirectedatMIEusersa. TurningMIEoffortolowpowermodeisanotherconsiderationthat
couldapplytoCT’sandX-rays(whichcanbeturnedoff)andMRIs(wheretheequipmentcouldbeturnedtolowestpowermode).GuidingtheMIEusersonhowtodothisalongwithexpertsinMIEwouldbeessentialforenergyrelatedbehaviourchange.
4) OptimizingenergyconsumptionofcoolingrequirementsforMIEequipmenta. Coolingsystemequipmentarerequiredtoensurecritical
environmentalrequirementsaremetforMIEbutthesecanconsumesignificantenergythrough,forexample,theairhandlingunits.OptimizingthesesystemsalongwiththeMIEenergyuseandpowermodecanresultinenergysavings.
5) DevelopmentofaBusinessCaseforMIEpurchasingpersonnela. CostinformationonMIEandancillaryequipmentcouldbedeveloped
intoaBusinessCaseforequipmentpurchasersandhospitalpurchasingagentssothatenergyoperatingcostscanbeconsideredaspartofthenewequipmentevaluation.
i. MRIs:Averagecoststooperaterangedfrom$20,000to$30,000peryearjustfortheMRI.Addingintheancillaryenergyfromtheequipmentandcoolingcanbringthisamountupconsiderably.
ii. CTs:Averagecoststooperaterangedfrom$3,000to$6,000peryear,justfortheCTequipment.Addingintheancillaryenergyfromtheequipmentandcoolingcanbringthisamountupconsiderably.ManyhospitalshavemorethanoneCT.
iii. X-rays:Averagecoststooperaterangedfrom$100peryearwhennoscanninghastakenplace,andapproximately$400whentheyarebeingused.ThesecostsarejustfortheX-rayequipment.Addingintheancillaryenergyfromtheequipmentandcoolingcanbringthisamountupconsiderably.ManyhospitalshavemorethanoneX-raywhichwouldincreasethecontributionofthetotaloperatingexpensemultifold.
6
Table of Contents
1.INTRODUCTION 7
1.1OBJECTIVESOFTHISPROJECT 7
2.BACKGROUND 9
2.1MIEINITIATIVESINTHEUS 92.2MIEINITIATIVESINEUROPE 112.3MEIINITIATIVESINCANADA 132.4MEDICALIMAGINGANDANCILLARYEQUIPMENT 14
3.METHODOLOGY 19
4.RESULTS 22
NUMBEROFTESTSANDDATAPOINTS 22POWERCONSUMPTIONATLOWPOWERANDSTANDBYMODE 24
5.DISCUSSION 34
OPPORTUNITIESFORENERGYSTAR 35
6.CONCLUSIONS 43
APPENDIX1:DETAILEDTESTINGGUIDANCEFORDIFFERENTSCANMODES 45
APPENDIX2:EUGREENPUBLICPROCUREMENT(GPP)FORHEALTHCAREELECTRICALANDELECTRONICEQUIPMENT 47
APPENDIX3:MIEENERGYMEASUREMENTDATA 54
APPENDIX3.1:MRIENERGYCONSUMPTIONDATA 56
APPENDIX3.1.1MRIENERGYCONSUMPTIONDATASITE#1 56APPENDIX3.1.2MRIENERGYCONSUMPTIONDATASITE#2 75
APPENDIX3.2:CTDATA 95
APPENDIX3.2.1CTENERGYCONSUMPTIONDATASITE#1 96APPENDIX3.2.2CT#2ENERGYCONSUMPTIONSITE#1 105APPENDIX3.2.3CTENERGYCONSUMPTIONDATASITE#2 111APPENDIX3.2.4CTENERGYCONSUMPTIONDATASITE#3 132
APPENDIX3.3:X-RAYDATA 133
APPENDIX3.3.1:X-RAYDATASITE#1CTENERGYCONSUMPTIONDATASITE#3 133APPENDIX3.3.2X-RAYSITE1 141
7
1. Introduction ENERGYSTARproductshavebeenavailableinmanyconsumerandbusinesscategoriestohelppurchasersselectthemostenergyefficiencyproductsinaspecificcategory.OneproductcategorythatcurrentlyhasnoENERGYSTARdesignationisthehighenergyconsumingmedicalimagingequipmentusedinhospitalsacrossNorthAmerica.TheUnitedStatesEnvironmentalProtectionAgency(USEPA)hastakentheleadinassessingtheopportunitytodesignateanewcategoryofmedicalimagingequipmentasENERGYSTARcertifiedbutwerelackinginformationabouttheenergyconsumptionoftheseproductsinuse.NaturalResourcesCanada(NRCan)hasbeenprovidingassistancetotheUSEPAtoaddresstheseopportunitiesNorthAmerican-wide.
1.1 Objectives of this Project TheCanadianCoalitionforGreenHealthCare(TheCoalition)undertookthisstudyprimarilytoacceleratethedevelopmentofthemedicalimagingequipment(MIE)ENERGYSTARspecification.Tothisend,theCoalitiongatheredandanalyzedenergydataforthreeMIEtypesworkingwithourpartnerhospitals.OurpartnerhospitalswhovolunteeredtotakepartinthisstudywereNanaimoGeneralHospital(NGH)ofIslandHealthcareinBritishColumbia(BC),theHospitalforSickChildren(SickKids)inOntarioandtheUniversityHealthNetwork(UHN)inOntario.Partneringhospitals,aswellasoneofouroriginalfunders,BCHydro,wereinterestedingainingabetterunderstandingoftheimpactMIEhaveonoverallhospitalbuildingenergyconsumption,andtolearnwhatkindsofactionshospitalstaffcouldtaketoreducetheenergyconsumptionoftheseequipmenttypesintheshort-andlong-term.ThesixMIEtypesthatwereintheoriginalscopeofthisstudywouldhaveincluded12testingeventsresultingin36datapoints.EachofthesixMIEtypeswouldbetestedtwice,andforeachtesttherewouldbethreedatapointsidentifyinglowpowermode/standby/idlepowermodeenergyconsumption.Eachtestingeventwouldlastlessthan30minuteseach.ThesixtypesofMIEofinterestwere:
1. ComputedTomography(CT)2. GeneralRadiography(X-ray)3. MagneticResonanceImaging(MRI)4. MammographyEquipment5. NuclearImaging6. UltrasoundImaging/Sonography
Duringthecourseofthisstudy,energyconsumptiondatawereobtainedfromthreetypesofMIEwith100sofdatapointscollectedoverseveralweeksoftestingduring
8
eight(8)testingevents,wherethetestingtimewasextendedfarbeyondwhatwasoriginallyexpected.Mostofthetestingperiodslastedfromthreeto11days,andenergyconsumptiondatawereobtainedforlowpowermode,standbybypowermodeandactivepowermode.Withthisenhanceddatacollection,theresultscouldalsorevealinformationonthelengthoftimetheequipmentspentinthedifferentpowermodesandbeusedtopredictannualenergyconsumptionandcosts.TestingwasundertakenwiththefollowingMIE:
1. ComputedTomography(CT)2. GeneralRadiography(X-ray)3. MagneticResonanceImaging(MRI)
9
2. Background
2.1 MIE Initiatives in the US TheUSinitiatedtheENERGYSTARprogramin1992asavoluntaryclimateprotectionprogramprovidingastrategicapproachtoenergymanagementbypromotingenergyefficientproductsandpractices.Theprogramprovidestoolsandresourcestohelpsavemoneyandprotecttheenvironment.ENERGYSTARlabeledproductsthatarecurrentlyavailableinclude:lighting,homeenvelopproducts,heatingandcooling,officeequipment,commercialfoodservicesequipment,homeapplicantsandhomeelectronics.TheUSDepartmentofEnergy(DOE)estimatedthatthemedicalequipmentinahospitalmakesup18%ofthefacility'senergyuse1.In2009,theUSDOEidentifiedmedicalequipmentasamajorareaofpotentialenergysavings.TheDOEassistedindevelopingtheHealthcareEnergyAlliance(HEA),aforuminwhichhealthcareleadersworkedtogetherwithDOE,itsnationallaboratories,andnationalbuildingorganizationstoacceleratemarketadoptionofadvancedenergystrategiesandtechnologies.TheHEASteeringCommitteeidentifiedfiveareasoffocusinhospitalbuildingsystemsandoperationsthatrequiredresearchoninnovative,cost-effectivetechnologiesandbestpracticestoolkits.OneofthesewasMedicalEquipmentandPlugLoads,andasaresult,strategiestodecreaseenergyconsumedbydiagnosticandtherapeuticequipment,aswellasgeneralhospitalplugloadswasundertaken.A2014reportfromtheNationalRenewableEnergyLaboratory(NREL):HealthcareEnergyEnd-UseMonitoring2lookedatthepowerconsumptionofvariousMIEinhospitalsandmedicalclinicsoveraone-yearperiodandidentifiedvariabilityintheMIEloadprofiles.Theauthorssuggestthattherecouldbeanopportunityfordevicemanufacturerstoimprovetheenergyefficiencyof‘idle’or‘lowpowermodes’andmakeaccessingthesepowermodeseasierfortheuser,aswellasensuringthattheMIEwillpowerupquicklyasneeded.Inaddition,itwasfoundthatmostofthisequipmentisnotusedthroughoutthenightandthatopportunitiestopowerdownspecificequipmentshouldbeexaminedmoreclosely.InitialanalysisbytheUSEPAshowedthatmostmedicalimagingproductsusesignificantenergy,evenwheninready-to-scanorlow-powermode.TheEPAbelievedthatconsiderablesavingscouldbegainedfromavoidingunnecessary
1 U.S. Department of Energy. "Hospitals Pulling the Plug on Energy-Wasting Electric Equipment and Procedures." July 2011 2 Healthcare Energy End-Use Monitoring – NREL report 2014
10
energyuseinjustthesemodes.TheEPAwasnotintendingtopursuerequirementsofanyactivescanmodesandwasintheearlieststagesofanENERGYSTARspecificationdevelopmentforMIEs.3Since2009,productmanufacturershaverespondedwithequipmentthatconservesenergywhilealsoimprovingpatientcare.NewgenerationsofMRIandCTscannersaresmaller,lighter,andhavescantimesthatareupto75percentfasterthanlegacyequipment—whichreducesradiationdosesandenergydemands,resultinginlowerenergycostsperpatient,aswellasadecreasedradiationdoseforpatients.Fasterscansalsoincreasepatientsatisfactionandthroughput,andimprovestaffworkflow.TheMIEequipment'slifetimeenergyuseshouldbefactoredintopurchasingdecisions.4 Figure1providesasummaryforfourMIEtypesandthecorrespondingunitenergyconsumption(UEC),thenumbersofeachtypeofMIE,andtheannualprojectedenergyconsumption(AEC)5.IntheUS,MRIsconstitutethelargestunitenergyconsumptionandprojectedannualenergyconsumption,followedbyCTs,X-raysandUltrasounds.Figure1:MiscellaneousEnd-UseServicesandEquipmentEnergyConsumptionSummaryintheUS
3Greenhealthjournal,Fall20154 A prescription for energy efficiency. Health Care Design. March 2013. http://www.healthcaredesignmagazine.com/architecture/prescription-energy-efficiency/ 5Energy Savings Potential and RD&D Opportunities for Commercial Building Appliances (2015 Update) W. Goetzler, M. Guernsey, K. Foley, J. Young, G. Chung June 2016. DOE Energy Efficiency and Renewable Energy pg 145 https://energy.gov/sites/prod/files/2016/06/f32/DOE-BTO%20Comml%20Appl%20Report%20-%20Full%20Report_0.pdf
11
2.2 MIE Initiatives in Europe TheEnergyRelatedProducts(Ecodesign)DirectivegivesauthoritytotheEuropeanCommission(EC)tosetecodesignrequirementsthroughnewregulationsforanygroupofproductswhichusesenergy.In2007,MedicalDeviceswereidentifiedasa“PriorityA”productgroupbytheECforfutureregulation.Toavoidadversebusinessimpacts(unnecessarycostsandlossofflexibilityinproductdesign),theMIEbusinesscommunitydevelopedanalternativeapproachallowedundertheEcodesignDirectiveAnnexVIII(Self-RegulatoryInitiativeforanindustrysector)6.OneestimatefromDenmarkindicatesthatmedicalequipmentcomprises18%ofhospitalenergyuse,butactualtestinginDenmarksawvaluesashighas50%oftheenergyrequirementsifthemeasurementsincludedtheadditionalenergy/HVACrequiredtomaintaintemperaturerelatedtouserrequirementsandmedicalequipment.7TheEuropeanCoordinationCommitteeoftheRadiological,ElectromedicalandHealthcareITIndustry(COCIR)developedtheSelfRegulatoryInitiative(SRI)forMedicalImagingEquipment.ThisInitiative,launchedin2009andofficiallyacknowledgedbytheEuropeanCommissionin2012,aimsatreducingtheenvironmentalimpactsofmedicalimagingdevices,andrepresentstheproactiveapproachofCOCIRtowardssustainablehealthcareandthecirculareconomy.COCIRhaveproducedsixstatusreportstodate,thelatestonereleasedinSeptember20168.Themajorinternationalequipmentmanufacturersparticipateinthisinitiative.Forexample,fromtheMRImanufacturingsectorparticipantsincludeGE,Phillips,Siemens,ToshibaandHitachi.COCIRdevelopedstandardizedtestingprotocolsforMIEwhichwereusedasthebasisforthetestmethodsdevelopedfortheENERGYSTARMIEtestingprocess–‘FinalDraftTestMethodForDeterminingMedicalImagingEquipmentEnergyUse–Rev.Aug2014’thatwasusedasthebasisforproducttestingfortheCanadianstudy.TheCOCIRSRIreportssignificantreductioninannualenergyconsumptionforMIEsuchasMRIsfrom2011–2015.ManufacturershavecollectivelydecreasedtheenergyconsumptionoftheMRIs.AsshowninFigure2,in2015thedailyaverageenergyconsumptionperunitforMRIequipmentdecreasedto176.91kWh/unit
6http://www.eceee.org/ecodesign/products/medical-imaging-equipment/7Energy efficiency in hospitals and laboratories (6-337-11), 2011. Anders Hjorth Jensen, Danish Energy Saving Trust, Denmark, Peter Maagøe Petersen, Viegand & Maagøe ApS, Denmark http://proceedings.eceee.org/visabstrakt.php?event=1&doc=6-337-11 8 COCIR Self-Regulatory Initiative For The Ecodesign of Medical Imaging Equipment Status Report 2015 www.cocir.org/fileadmin/6_Initiatives_SRI/SRI_Status_Report/SRI_Status_Report_2015_-_21_September_2016.pdf
12
showinga21%reductioncomparedto2011(225.92kWh/unit)anda5%comparedto2014.Figure2:MRIachievements:Calculatedvaluesforyear2011-2015andforecastuntil20179
However,comparingenergyconsumptionvalues,forexample,inMRIsin2015fromfivecompaniesshowsthereisagreaterthan25%spreadintheaveragedailyenergyconsumptionasprovidedinFigure3below.Figure3:COCIRmemberreportsofaverageMRIdailyenergyconsumptiontrendsperyear 10
PastworkalsoincludedinformingMIEuserstouselowpowerandpower-downmodesduringthenightwhentheMIEsarenotinuse.BrochureswerecreatedforMRIandCTin2014:
• COCIRbrochure:“COCIRMRIGuidelinesforUsersonSavingEnergy-GoodEnvironmentalPractice
9COCIR 2015 report pg 18 http://www.cocir.org/fileadmin/6_Initiatives_SRI/SRI_Status_Report/SRI_Status_Report_2015_-_21_September_2016.pdf 10 COCIR page 18 http://www.cocir.org/fileadmin/6_Initiatives_SRI/SRI_Status_Report/SRI_Status_Report_2015_-_21_September_2016.pdf
13
• COCIRGuidelinesonenergysavingonComputedTomography–Contributiontohealthcareenvironmentalsustainability
TheCOCIRobjectivesalsoincludeeco-designsthatcontributetothe‘circulareconomy’-anobjectiveoftheEU.TheCOCIRhasconcludedthattheirgreatestimpactslieinreuseandrefurbishment.
2.3 MEI Initiatives in Canada NaturalResourcesCanada(NRCan)hasworkedcloselywiththeUSEPAontheENERGYSTARprogramsinceitsinceptioninCanada,whichnowincludesPortfolioManager,usedasanenergybenchmarkingtoolfortheindustrial,commercialandinstitutionalsector.TheSurveyofCommercialandInstitutionalEnergyUse(SCIEU)isintendedtoproducestatisticalestimatesofenergyuseandestablishbaselineenergyconsumptionfigurestosupportenergyefficiencypolicyandprogramdevelopment.Thedataalsoformsthebasisofthe1-100performancescoresusedinNRCan’sCanadianadaptationoftheU.S.EPA’sENERGYSTARPortfolioManagerenergybenchmarkingsystem.11AquestiononMRIshasbeenincludedinthehospitalenergyusesurveyin2015. In2014,NRCancommissionedastudythatincludedmedicalimagingequipmentquantitiesandenergyconsumptioninCanada.12Thepurposeofthisstudywasto:§ CharacterizetheCanadianmedicalequipmentmarket,§ Estimatemedicalequipmentenergyuse,§ Assess technology characteristics and the capacity for energy performance
improvements,§ Evaluateenergysavingsopportunities,§ Exploremarkettransformationopportunities,and§ Makerecommendationsforfuturework.
Thereportfoundthatfourmedicalimagingmodalitieswereinthetopfivemostenergyconsumingmedicaldevicetypesinhospitals:MRIs,x-rayscanners,ultrasound,andCTscanners.
TheCanadianAgencyforDrugsandTechnologiesinHealth(CADTH)releasedtheCanadianMedicalImagingInventory,2016.13Thisreportsummarizedinformation
11 www.nrcan.gc.ca/energy/efficiency/buildings/energy-benchmarking/update/getready/1673112Energy Savings Opportunities for Medical Equipment, Report to NRCan by ICF International, February 2015.
14
fromasurveyofMIEusers,whichweremostlypublichealthcaresites.ThesixMIEtypestheygatheredinformationonarelistedbelow,withthefollowingresultsofinteresttothisreport:
• Computedtomography(CT)o 538unitsinCanada(61tobepurchasedinthenext2years)o CTunitsoperateforamedianof63hoursperweek,and10hoursper
day.Mostoperateatweekends• Magneticresonanceimaging(MRI)
o 340unitsinCanada(35tobepurchasedinnext2years)o MRIunitsoperateforamedianof72.2hoursperweek,and13.5
hoursperday.Mostoperateatweekends• Single-photonemissioncomputedtomography(SPECT)
o 264UnitsinCanada• Positronemissiontomography–computedtomography(PET-CT)
o 47unitsinCanada• Positronemissiontomography–magneticresonanceimaging(PET-MRI)
o 2unitsinCanada• Single-photonemissioncomputedtomography–computedtomography
(SPECT-CT)o 214unitsinCanada
OfnotearetheincreasingnumbersofthenewerhybridCTsandMRIs.
2.4 Medical Imaging and Ancillary Equipment ThissectiondescribesthegeneralcharacteristicsoftheMIEresearchedinthisstudy,andtheancillaryenergyconsumingequipmentintheassociatedrooms.WhileonlytheMIEenergyconsumptionwasmonitoredinthisstudy,itshouldbenotedthatthereareotherenergyconsumingequipmentrelatedtotheMIEwhichaddstothetotalenergyconsumptionvaluesofMIE.OurteamundertookareviewofancillaryequipmentrelatedtothespecificMIE,whichisrecordedbelow.1. ComputedTomography(CT):Technologythatcreatesacomputer-generated
3Dimagefromatwo-dimensionalX-rayimagestakenaroundasingleaxisofrotation.CTscansuseX-raystoproduceprecisecross-sectionalimagesofanatomicalstructuresandspaceswithinobjects.Machinesusedinmedicalfacilitiestypicallyconsistofaplatform,wherethepatientlies,andaCATmachinewithanopeninginthecenterforthepatienttopassthrough.AnX-RaytubeandanarrayofX-RaydetectorsaremountedonarotatingringthatislocatedinsidetheCATmachineandsurroundstheopening.MostoftheenergyconsumedduringthisprocessisusedtooperatetheX-Raycomponents.Energyisalsorequiredtooperateacomputerfordigitalimageprocessingandcontrols,anddriveanelectricmotorrequiredtorotatetheringandtheattachedX-Ray
13Canadian Medical Imaging Inventory, March 2016. CADTH www.cadth.ca/canadian-medical-imaging-inventory-2015
15
equipmentwhilethemachineisoperating.13
2. MagneticResonanceImaging(MRI):Technologyusedtoobtainhighlyrefinedimagesofthebody’sinterior.Itemploysmagnetsthatpolarizeandexcitehydrogennucleiinwatermoleculeswithintissuesandcreates2Dimages.MRIscreateamagneticfieldbypassinganelectriccurrentthroughwirecoils.MostMRIsusesuperconductingmagnetstomaintainlowresistivelossesinthewire.Superconductingmagnetsystemsrequirecontinuouscryogenicrefrigeration,whichconsumeroughly40%ofaMRI’stotalenergyconsumption.13
AsummaryofancillaryenergyconsumingequipmentforboththeCTandMRIequipmentroomsareasfollows:
1) CT/MRIEquipmentRoom• CT/MRIGantry• CT/MRItable• ArticulatingArms• Monitors–VideoandVitalSigns• InjectionEquipment
2) AncillaryEquipment• Chillerforchilledwaterloopforequipmentcooling• DedicatedHVACsystemforroomcooling(In-lineLiebert)
3) Technician’sRoom• Multiplemonitors&Servers• Dedicatedcooling(ductlesssplitorLiebert)
4) MechanicalRoom(Water)• Water/Glycolclosedlooptochillerandtoequipment• By-passtocitywaterasback-upforcooling
5) ElectricalRoom• Dedicatedspaceforelectricalpanelsandtransformerequipment• Dedicatedcooling(ductlesssplitorLiebert)
6) PatientChangeRoomandWaitingArea
TheaverageenergyconsumptionofaCTinthedifferentpowermodesshowninFigure4,showsthecontributionsthedifferentancillaryequipmentmaketothepowerdrawatthedifferentmodes.
16
Figure4:EnergyconsumptionoveratypicaldayinLowPower,IdleandScanmodeallocatedtothedifferentmodulesoftheCTscanner.14
3. Mammography:Thisequipmentuseslow-doseX-raystoexaminethehuman
breastfortumorsandcysts.Mammographyequipmentcanbeeitheranalog,projectinglow-doseX-raysonfilm,ordigital,convertingX-raysintoelectricalsignalsthatproducedigitalimages.Asummaryofancillaryenergyconsumptionequipmentinthemammographyroomsareasfollows:
1) MammographyEquipmentRoom• MammographyUnit• Monitors–VideoandVitalSigns
2) Technician’sRoom• Multiplemonitors&Servers• Dedicatedcooling(ductlesssplitorLiebert)
3) PatientChangeRoomandWaitingArea4) OfficeandConsultationSpace
4. NuclearImaging:Apatientconsumesshort-livedisotopeswhichemitradiation
thatismeasured,commonlywiththeuseofagammacamera.Scintigraphy,singleprotonemissioncomputedtomography(SPECT),andpositronemissiontomography(PET)aretypesofnuclearimagingtechnologies.Scintigraphyproduces2Dimages,whileSPECTandPETtechnologiesproduce3Dimages.
14 COCIR 2015 pg 53 http://www.cocir.org/fileadmin/6_Initiatives_SRI/SRI_Status_Report/SRI_Status_Report_2015_-_21_September_2016.pdf
17
Asummaryofancillaryenergyconsumingequipmentfornuclearimagingequipmentroomsareasfollows:
1) NuclearImagingRoom• NuclearImagingequipment• ArticulatingArms• Monitors–VideoandVitalSigns• InjectionEquipment
2) Technician’sRoom• Multiplemonitors&Servers• Dedicatedcooling(ductlesssplitorLiebert)
3) ElectricalRoom/Space• Dedicatedspaceforelectricalpanelsandtransformerequipment• Dedicatedcooling(ductlesssplitorLiebert)
4) PatientChangeRoomandWaitingArea
5. UltrasoundImaging/Sonography:Thistechnologyexposesabodyparttohigh-frequencysoundwavesthatarereflectedbytissuesinthebodytoproducereal-time2Dand3Dimages.Asummaryofancillaryenergyconsumingequipmentforultrasoundimagingequipmentroomsareasfollows:
1) UltrasoundRoom• Multiplemonitors&Ultrasoundunit• Dedicatedcooling(ductlesssplitorLiebert)
6. GeneralRadiography(X-ray):AnX-rayimageisproducedwhenasmallamountofionizingradiationpassesthroughthebody.TheabilityofX-raystopenetratetissuesandbonesvariesaccordingtothetissue’scompositionandmass.ThestepofexposingthepatienttotheX-Raytypicallylastafewhundredthsofasecond,butcandraw60-80kWinstantaneously.AseriesofuserandequipmenttaskstopositionthepatientanddevelopthefilmalsocontributetotheaverageoperatingenergyconsumptionofX-Raymachines.
Asummaryofancillaryenergyconsumingequipmentforgeneralradiographyequipmentroomsareasfollows:
1) X-ray/FluoroscopyEquipmentRoom
• X-rayunit• X-raytable&VerticalBackdrop• ArticulatingArms
18
• Monitors–VideoandVitalSigns• InjectionEquipment
2) Technician’sRoom/WorkSpace• Multiplemonitors&Servers• Dedicatedcooling(ductlesssplitorLiebert)
3) ElectricalCloset• Dedicatedspaceforelectricalpanelsandtransformerequipment• Dedicatedcooling(ductlesssplitorLiebert)
4) PatientChangeRoomandWaitingArea
19
3. Methodology TopreparefortheenergymeasurementstheteamundertookreviewsofthereferencesprovidedbytheUSEPA:1. Reviewofgeneraltestingproceduresformedicalelectricalequipment:
a. Generaltestingproceduresformedicalelectricalequipment–reportbyTheInternationalElectrotechnicalCommission(IEC)62354Edition3.02014-09
i. Thisincludedreferencestogeneraltestingconditions,inputpower,andpowermetershallbeasspecifiedinIEC62354
ii. Productsshallbetestedintheir“as-shipped”configuration,whichincludesbothhardwareconfigurationandsystemsettings,unlessotherwisespecified.
2. ReviewofUSEPAdevelopedsamplingtemplates:a. ENERGYSTAR®ProgramRequirementsProductSpecificationforMedical
ImagingEquipmentFinalDraftTestMethodForDeterminingMedicalImagingEquipmentEnergyUseRev.Aug–201415
Theteamthenconsolidatedthetestinginformationintoatestprocessthatourpartnerhospitalswerecomfortablewith.ThehospitalswerealsointerestedingatheringthetotalenergyuseoftheMIE,includingactivemodeenergyuse,andwereassistedbytheprojectexpertstoundertakethesemeasurements.
EachhospitalidentifiedMIEforpossibleinclusioninthestudy.OfnotewerethefollowingofinteresttotheUSEPA:
a. Abroadrangeofmanufacturerswaspreferred.b. MIEsuitableforthestudywerelessthanthreeyearsold(2013and
newer)wherepossible.c. Manufacturesname,modelandinstallationyearwereidentified.d. TheUSEPApriorityinterestswereMRIsandCTs
ThefollowinggeneralapproachwasundertakentomeasureenergyconsumptionoftheMIEinthisstudy:1. Energymeasurementswereundertakenateachsitebyauthorizedhospitalstaff
(i.e.electriciansauthorizedtomeasureenergyconsumptiononmedicalimagingequipment).
2. Recordingtestinginformation
15EnergyStarDraftTestMethodforMedicalImagingEquipmenthttps://www.energystar.gov/sites/default/files/ENERGY%20STAR%20Medical%20Imaging%20Equipment%20Final%20Draft%20Test%20Method.pdf
20
a. USEPAprovidedadraftdatasheetforrecordingdata.OurteamhaseditedthisbasedonatrialatUHN,andtheneedbyhospitalstounderstandtotalenergyconsumption.
3. Powerloggersa. Powerloggersownedbyeachhospitalwereusedwhereavailable.Where
required,thepowerloggersweresentforrecalibrationifnotcalibratedwithinthelasttwoyears.AnadditionalpowerloggerwasborrowedfromTorontoHydro.Apowerloggerwasalsopurchasedforuseinthisstudy.
b. Allpowerloggerswerecapableofmeasuringpolyphasevoltageandcurrent
4. Testingenvironmenta. Ambienttemperatureshouldbewithin23C+/-5Cb. Relativehumiditywasbetween15%and80%
5. Timelengthoftestsa. Eachsitechosealengthoftimesuitablefortheirneeds.
6. PowermodemeasurementswereasperCOCIRandENERGYSTARguidance.AmoredetaileddescriptionofthemeasuringguidanceisprovidedinAppendix1.
a. Powermodemeasurementswererecordedforthefollowing,whenavailableontheMIE:
i. Offmode(sleepmode,service/evaluationmode)1. Thesystemisshutdownwithacmainsoff,accordingtothe
usermanual.Thesystemconsumesnoenergy.2. Note:forMRI,offmodecorrespondstothelowestpower
modebecausetheequipmentcannotbeshutdowncompletely.
ii. Lowpowermode1. Thismoderepresentstheminimumenergyconsumption
statethattheusercanselectaccordingtotheusermanual.ThepowerconsumptionislowerthanReady-to-scanandhigherthanOffmode.
iii. Ready-to-scan(idle)mode1. Thismoderepresentsthestateofthesystembetween
individualscans,wherenoscanhasbeenprescribed(e.g.,duringpatienthandling,dataarchiving,examinationplanning,orcontrastagentinjection).ThismodedoesnotincludepotentialmechanicalmovementssuchasX-raytuberotororgantryrotation.
iv. Scan(active)mode1. Thesystemisactivelyscanningthepatienttogenerate
images.Thecomputingsysteminterpretsthedataandgeneratestheimage.ThismodealsoincludesanypotentialmechanicalmovementssuchasX-raytuberotororgantryrotation.
21
2. Note:ThisdatawasnotrequiredfortheENERGYSTARevaluationbutwasofinteresttoparticipatinghospitals.
7. Numberoftestsa. TheCoalitionproposedtwotestsofeachoftheoriginalsixMIEproduct
typesifpossible,withaminimumof12testingevents.Eachofthesetestingeventswouldresultinthreedatapoints,withatotalof36datapoints.Undertakingthesetestswoulddependonthehospitalschedulesformanpowerandequipmentavailability.
8. ResourcesrequiredtoundertakeenergyconsumptiontestsofMIEa. Intermsoftheresourcesrequiredtoundertakeatest,COCIRhas
identifiedthefollowingtasksandtechnicians/specialistsrequiredtomeasureonetargetMRIequipment:16
Figure5:ResourcesrequiredtoundertakeoneenergyconsumptiontestofMRI
16 COCIR Status Report 2014 pg 32 www.cocir.org/fileadmin/6_Initiatives_SRI/SRI_Status_Report/COCIR_SRI_Status_Report_2014_-_10092015.pdf
22
4. Results MIEenergyconsumptionresultswereobtainedfromhospitalstaffwhoutilizedpowerloggersasperthetestingprocesstoundertaketheactualmeasurement.RawdatafromthesemeasurementsareprovidedintheMIEEnergyMeasurementDataAppendix3.
4.1 Number of tests and data points OriginallytheCoalitionproposedtwotestsofeachoftheoriginalsixMIEproducttypesifpossible,withaminimumof12testingevents.Eachofthesetestingeventswouldresultinthreedatapoints,withatotalof36datapoints.Undertakingthesetestswoulddependonthehospitalschedulesformanpowerandequipmentavailability.Inanenvironmentwherepatientoutcomestakepriority,notallthesetestswereabletobeundertaken.ActualMIEtestingoccurredwiththree(3)MIEtypesandeight(8)separatetestingevents:
a. MagneticResonanceImaging(MRI)b. ComputedTomography(CT)c. GeneralRadiography(X-ray)
PartnerhospitalswantedtouselongertestingperiodstogainabetterunderstandingoftotalenergyconsumptionfromMIEattheirfacilities.Usinglongertestingperiodsresultedin100sofdatapoints(insteadofthe36originallyagreedto)andmuchmorereliabledatafromoffmode,lowpowermodeandstand-bymodes.Mostofthedatameasurementstookplaceoveraperiodofdays–fromthree(3)daystoeleven(11)days.Onlyonetesteventwasforapointmeasurementoftwo(2)minutes.AsummaryofthetestlengthoftimewherethepowerloggerswereleftontheequipmentforvaryinglengthsoftimeisprovidedinFigure6below:Figure6:Powerconsumptiontestingevents,testlengthanddataacquisitionintervalsMEIType TestingEventand
SiteTestLength DataAcquisition
Intervals(minsorsecs)
MRI 1. Site1 11days 6minsMRI 2. Site2 7days 1minCT 3. Site1 7days 6minsCT 4. Site1 7days 6minsCT 5. Site2 8days 1minCT 6. Site3 2min 1secX-ray 7. Site1 6days 6minsX-ray 8. Site1 3days 6mins
23
Variationsindataacquisitionintervalsaroseoutofquestionsondataqualitypossiblyrelatedtotheenergycollectioninterval.Increasedresolutionofdataforenergyconsumptionusingone(1)secintervalsresultedinanexpandedviewoftheenergyconsumptionpatternasseeninFigure7below,whichshowsenergyconsumptionduringaCTscanatSite3.Identifiedonthegraphisthegantrytablemovement,thefirsttwoscans,whichare‘dualscans’andathirdscan,ahelicalscan,thatconsumesthehighestenergy.Incomparison,datafromsixminandoneminintervalsforCTscansatSites2andSite1areprovidedinFigures8and9.Figure7:Powerconsumption(kW)patternusingonesecintervalsforCTatSite3
Figure8:Samplefromtimeseriesofpowerconsumption(kW)foreachminuteovereachhour,overeightdays(Site2)
24
Figure9:SamplefromtimeseriesofpowerconsumptionusingsixminintervalsforCTatSite1
4.2 Power consumption at low power and standby mode Datafromthepowerloggertestingeventswerecompiledandassessedforlowpowerandstandbypowermodevalues.AsummaryofallmeasureddataisprovidedintheAppendix3.Figures10and11showsummarygraphsofpowerconsumptionforthetwoMRIsmeasured.Thelowestpowerconsumptionvaluesdifferslightly,butthetimespentatthelowerpowermodesvary,likelyduetoactualusageforscanning.
25
Figure10:MRIenergyconsumption(kW)percentageateachpowerrangeatSite1
Figure11:MRIenergyconsumption(kW)percentageateachpowerrangeatSite2Figures12,13and14showsummarygraphsofpowerconsumptionforthreeCTsmeasuredforseveraldays.ExamplesoftheCTrawdataareprovidedinFigures7,8and9.DatafromeachMIEweregraphedandpowerconsumptionwasrecorded.Itisevidentthatthelowestpowerconsumptionvaluesdifferslightly.Inaddition,itwasnotedfromthetimeseriesofpowerconsumptiondata,thatineachcasetheCTwenttoalowerpowerconsumption(oftenduringtimeswhenscanningwasnot
0%
5%
10%
15%
20%
25%
30%
35%
[0,10)
[10,12)
[12,14)
[14,16)
[16,18)
[18,20)
[20,22)
[22,24)
[24,26)
[26,28)
[28,30)
[30,32)
[32,34)
[34,36)
[36,38)
[38,40)
[40,42)
[42,44)
[44,46)
[46,48)
[48,50)
[50,9999)
Power(kW)
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
12-14
14-16
16-18
18-20
20-22
22-24
24-26
26-28
28-30
30-32
32-34
34-36
36-38
38-40
40-42
42-44
44-46
46-48
50-52
52-54
54-56
56-58En
ergyconsumptionpercentage
Powerconsumptiongroupsbasedonvalue(kW)
26
common),andreturnedtothereadytoscanmode.InFigure13,thepowerconsumptionreducedfromapproximatelytwotoonekW,andapproximately3.7kWasthereadytoscanmode.Figure12:CTpowerconsumption(kW)percentageateachpowerrangeatSite1
Figure13:CTpowerconsumption(kW)showingdropinkWatSite1
InFigure14,and15,thepowerconsumptionreducedfromalowpowermode,(whichalsoappearedtobeareadytoscanmode)oftwotobelow0.5kW.ThepowerconsumptionalsodroppedasecondtimefromtwotoapproximatelyonekW.
0%
10%
20%
30%
40%
50%
60%
70%
[0,1)
[1,2)
[2,3)
[3,4)
[4,5)
[5,6)
[6,7)
[7,8)
[8,9)
[9,10)
[10,11)
[11,12)
[12,13)
[13,14)
[14,15)
[15,9999)
Power(kW)
27
Figure14:CTenergyconsumption(kW)percentageateachpowerrangeatSite1(test#2)
Figure15:CTpowerconsumption(kW)showingdropinkWatSite1(test#2)
InFigures16and17thereadytoscanmodeinthisCTisapproximately4.8kWbutalsodropstoapproximately0.7kWasalowestpowerconsumptionstage.
0%
10%
20%
30%
40%
50%
60%
70%
80%
[0,0.5)
[0.5,1)
[1,2)
[2,3)
[3,4)
[4,5)
[5,6)
[6,7)
[7,8)
[8,9)
[9,10)
[10,11)
[11,12)
[12,13)
[13,14)
[14,15)
[15,16)
[16,17)
[17,9999)
Power(kW)
28
Figure16:CTenergyconsumption(kW)percentageateachpowerrangeatSite2
Figure17:CTpowerconsumption(kW)showingdropinkWatSite2
X-raypowerconsumptiondataisprovidedinFigures18and19.LowpowerconsumptioninthefirstX-rayisseenas0.18kW(Figure19),whileinFigures20and21,thepowerconsumptionwasconstantlyatapproximately0.08.AfterreviewofthetimeseriespowerconsumptiongraphsidentifiedinFigure21,(asprovidedinAppendix3.3)theredidnotappeartobeanyactualscanningevents.
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
[0,1)
[1,2)
[2,3)
[3,4)
[4,5)
[5,6)
[6,7)
[7,8)
[8,9)
[9,10)
[10,20)
[20,30)
[30,40)
[40,50)
[50,9999)
Energyconsumptionpercentage
Powerconsumptiongroupsbasedonvalue(kW)
29
Figure18:X-rayenergyconsumption(kW)percentageateachpowerrangeatSite1test#1
Figure19:X-raypowerconsumption(kW)showingdropinkWatSite1
0%
10%
20%
30%
40%
50%
60%
[0,0.1) [0.1,0.2)
[0.2,0.3)
[0.3,0.4)
[0.4,0.5)
[0.5,0.6)
[0.6,0.7)
[0.7,0.8)
[0.8,0.9)
[0.9,1) [1,1.1) [1.1,99)
Power(kW)
30
Figure20:Xrayenergyconsumption(kW)percentageateachpowerrangeatSite1test#2
Figure21:X-raypowerconsumption(kW)showingconsistentlylowkW(0.07-0.09)atSite1
Figure22providesasummaryoftheresultsofpowerconsumptionofthelowpowerandstandbypower(kW)forthethreeMIEtypesaswellasreference(REF)powerconsumptiondatafromotherpublishedsourcesofMIEenergydataforquickcomparisonpurposes.Alsocollectedwerereferencedata(REF)fromreportedvaluesfortheMIEinpublishedliterature.
0%
10%
20%
30%
40%
50%
60%
70%
[0,0.06) [0.06,0.07) [0.07,0.08) [0.08,0.09) [0.09,99)
Power(kW)
31
Figure22:Measuredenergyconsumption(kW)inlowpowerandstand-bypowermodesofthemedicalimagingequipment Site #
Medical Imaging Equipment Type Off Mode Low Power Mode (kW)
Standby Power Mode
(kW) Manufacturer Model Year
MRI 1 Siemens Magnetom Aera 2013 NA 14.5 2 Siemens Advento 2013 NA 13.9 18.4 REF NREL17 (pg
22) 11
13
REF COCIR18 2015 (pg 27)
9.3 14.6
REF Norway hospital19
9 17
CT 1 Siemens Flash 128
scan mode 2016 1.9 / 1 3.6
1 Siemens Edge 64 scan mode
2016 1.0 2.3
2 GE Lightspeed Discovery HD750
2012 0.7 4.5
3 Toshiba CAT Scan (b)
Aquilion One TSX-305A
2013 Option not available on this CT
6.25
REF NREL (pg 22) 3; 3; 11 X-RAY 1 Toshiba KX0-80S X-Ray
Generator 2015 0.18
1 Toshiba KXO-80XM X-Ray Generator with MDX-8000 Table aka Ultimax System
2015 0.08
REF Danish hospital study 2008/9 20
0.65
REF COCIR 2015 (pg 57)
0.15 0.6
17 Healthcare Energy End-Use. Monitoring. Michael Sheppy, Shanti Pless, and Feitau Kung. National Renewable Energy Laboratory www.nrel.gov/docs/fy14osti/61064.pdf 18 COCIR 2015 report pg 18 http://www.cocir.org/fileadmin/6_Initiatives_SRI/SRI_Status_Report/SRI_Status_Report_2015_-_21_September_2016.pdf 19 Equipment and Energy Usage in a Large Teaching Hospital in Norway Tarald Rohde1* and Robert Martinez2 1SINTEF, Technology and Society, Hospital Planning, Oslo, Norway 2Norconsult as, Sandvika, Norway Submitted October 2014. Accepted for publication April 2015. 20 http://proceedings.eceee.org/visabstrakt.php?event=1&doc=6-337-11
32
Notes: (a) MRI’s cannot be turned off. The manuals often call ‘low power mode’ as ‘off mode’. We record the lowest power mode of the MRI as ‘low power’ (b) This CT machine does not have a ‘low power mode’ and will stay on standby/ready-to-scan mode unless technicians shut off the computers. The Gantry is always powered and the technicians estimated 6 hrs to warm up the CT if it was de-energized. In 16 hrs active machines may scan ~50 patients, the minimum would be 4/hr. The machine tested was a research machine so it was not active. Test #1 duration: 2 hrs. Figure23providesthesummaryoftotalannualpowerconsumptionforenergyusedbytheMEIinallmodes:theready-to-scanandlowpowerenergyconsumptionandtheestimatedannualenergycoststooperatetheMIE.OfnotearethepercentagetimestheMIEspendsinthelowpower,readytoscanandoffmodes.Referencedata(REF)isalsoprovidedtoshowhowthisdatacompareswithotherpublisheddata. Figure24providesanexampleoftabulatedMRIrawdatafromhospitalSite2asanexampleofhowourrawdataweretabulated. Figure23:Estimatedtotal,ready-to-scanandlowpowerconsumptionandcosts Site # MIE Type Estimated Annual Energy
Consumption (kW/h)
Estimated Annual
Costs @ $0.15 kW/h
(CAD)
Total per Unit
(kWh)
Ready to Scan & Scan Mode
%
Low Power Mode
%
Off Mode
%
MRI 1 Siemens 190,687 33% NA $28,603 2 Siemens 130,897 17% 81% NA $19,634 REF21 DOE 111,000 REF COCIR 2015
(pg 18) 64,572
CT 1 Siemens 31,775 65% 11% $4,766 1 Siemens 21,652 73% 5% $3,248 2 GE 40,942 89% $6,141 3 Toshiba
CAT Scan (b) NA
REF22 DOE 41,000 REF COCIR 2015 (pg
11) 50% in use /50% in ready to scan mode
26,280 18,250 13,505
X-Ray 1 Toshiba 2,811 45% $422 1 Toshiba 689 99.8% $103 REF23 DOE 9,500
21Energy Savings Potential and RD&D Opportunities for Commercial Building Appliances (2015 Update) W. Goetzler, M. Guernsey, K. Foley, J. Young, G. Chung June 2016. DOE Energy Efficiency and Renewable Energy pg 14522ibid
33
23ibid
Summary of power consumption (kW) at one minute interval over the entire monitoring period
kWminute Range (kW)
Count of kWminute
Average of
kWminute (kW)
Sum of kWminute
(kW)
Energy Consumption Percentage
of each range
Energy Consumption (kWh) over
sampling period
Estimated Energy
Consumption (kWh) over One Year
Estimated Annual cost @ $0.15 per kWh
[0,1 0.0 NA 0.0 0.0% 0.0 0.0 $ - [13,14) 8837.0 13.9 122480.8 80.9% 2041.3 105916.3 $ 15,887.4 [14,15) 103.0 14.1 1456.2 1.0% 24.3 1259.3 $ 188.9 [15,16) 6.0 15.6 93.3 0.1% 1.6 80.7 $ 12.1 [16,17) 16.0 16.5 263.8 0.2% 4.4 228.1 $ 34.2 [17,18) 63.0 17.8 1120.5 0.7% 18.7 969.0 $ 145.3 [18,19) 374.0 18.4 6882.6 4.5% 114.7 5951.7 $ 892.8 [19,9999) 731.0 26.1 19071.6 12.6% 317.9 16492.3 $ 2,473.8 Grand Total 10130.0 14.9 151368.9 100% 2522.8 130897.5 $ 19,634.6
Figure24:MRI(Site#2)powerconsumptionandestimatedcostsatdifferentpowerranges
34
5. Discussion SixMIEtypeswereinitiallyidentifiedaspossibleprioritieswiththeobjectiveofobtainingtwodatasetsfromeachtypeofequipmentwhichwouldconsistofthreedatapointspermeasurementperiodforatotaloftwelve(12)testingeventsand36datapoints:1. ComputedTomography(CT)2. GeneralRadiography(X-ray)3. MagneticResonanceImaging(MRI)4. MammographyEquipment5. NuclearImaging6. UltrasoundImaging/SonographyAccessingMIEforenergymeasurementsischallenginginahospitalenvironmentwherethepriorityisalwayspatientcare.Asaresult,energyconsumptiondatafromonlythreetypesofMIEwereabletobemeasuredandincludedatotalofeight(8)testingevents:1. ComputedTomography(CT)2. GeneralRadiography(X-ray)3. MagneticResonanceImaging(MRI)However,becausethetestingeventsrangedfromthree(3)to11days,thedatafromthesethreeequipmenttypesweremuchmorereliable,providing100sofdatapoints,ratherthanjustthreedatapointspertestingeventwhichwouldhaveresultedin36datapointintotalfor12testingevents.Longermeasurementperiodsalsoallowedricherinformationaboutwhenandhowfrequentlytheequipmentwasusedandenabledthecalculationofestimatedannualenergyconsumptionandenergycosts.Theextendedmeasurementperiodshavealsoprovidedinsightsintoenergyreductionstrategiesthatwouldnotbeavailablethroughtheoriginaltestingprotocol.ThethreetypesofMIEwhichwerestudiedarealsosomeofthemostenergyintensiveMIEequipmentwithinhospitals,asnotedintheBackgroundsection(Figure1:MiscellaneousEnd-UseServicesandEquipmentEnergyConsumptionSummaryintheUSandinsection2.3MEIInitiativesinCanada).Testingthehighestenergyconsumingequipmentisalsoofinteresttohospitals,whichcanbegintoassesshowtheycouldproceedwithenergyconservationinitiativesrelatedtoMIE.ThisstudyhasalsobroadenedtheunderstandingofhowmuchenergyMIEconsumeduringtheiruseandwhentheyarenotinuse.TheresultsalsoprovidedexamplesoftheannualenergycostsfordifferenttypesofMIE.
35
5.1 Opportunities for ENERGY STAR Theresultsshowedthatinsomecasesthereweresignificantvariationsinenergyconsumedatthedifferentpowermodesperequipmenttype,andincomparison,toreferencevaluesobtainedfromtheliterature.TheyearoftheMIEtestedwhencomparedtoCOCIRvaluesneedstobeconsidered.
• MRI:o InFigure22resultsrevealedthattherewasovera25%differencein
thelowpowermodepowerconsumptionandinthestandbymodeinthetwoMRI’stestedwhencomparedtotheCOCIRvalues.
o However,manyoftheMRImanufacturershavereducedtheirpowerconsumptionsignificantlybetween2013(ageofMRIstested)and2015(COCIRexamples–seeFigure3).SincethetestedMRIsandtheCOCIRagesaredifferent,theageofthetwoMRIstestedmaybethereasonwhytherewassignificantdifferentbetweenthetestedMRIsandtheCOCIRvalues.
o Opportunitiestopowerdownequipmentwhennotinuse:§ No‘off’modeisavailableonMRIs,howeverancillary
equipment(suchascomputers)shouldbefurtherexaminedtoensurepoweringdownthesetypesofequipmentcanbeeasilydonetosaveenergywhentheequipmentisnotinuse.
§ DatafromthisreportsuggeststhatopportunitiesforENERGYSTARcertificationcouldbefurtherexploredforMRIsrelatedtoancillaryequipment,andpossiblyforlowpowerandstandbypowermodes.
• CTo Lowpowerconsumptionmode:DataprovidedinFigure22lowpower
modesvariedmorethan25%,regardlessofyear,andinonecasethetechnicianindicatedthattherewasnolowpoweroptionavailable.Grapheddata(Figures13,15and17)indicatedthatCTscanreachmuchlowerpowerconsumptionvaluesthantheCTsgenerallyachievedlowpowermodes.Thedifferenceinthesevaluesaregenerally50%lowerormore.NoCOCIRvaluesforCTwerefoundforcomparison.
§ DatafromthisreportsuggestedthatopportunitiesforEnergyStarcertificationcouldbefurtherexploredforCTsrelatedtolowerpowermode.
o Standbypowerconsumptionvariedover25%,regardlessofCTyear.§ DatafromthisreportsuggeststhatopportunitiesforENERGY
STARcertificationcouldbefurtherexploredforCTsrelatedtostandbypowermodes.
o Opportunitiestopowerdownequipmentwhennotinuse:§ CTequipmentisknowntotheindustryasoneoftheMIEwhich
couldbepowereddownwhennotinuse,iftheequipmentcanbebroughtbacktooperationallevelaccordingtotheneedsoftheuser.Manufacturesshouldbeencouragedtodevelop
36
protocolstoassistequipmentenduserstopowerdownequipmentasmuchaspossiblewhennotinuse.
§ Ancillaryequipment(suchascomputers)shouldbefurtherexaminedtoensurepoweringdownthesetypesofequipmentcanbeeasilydonetosaveenergywhentheequipmentisnotinuse.
§ DatafromthisreportsuggeststhatopportunitiesforENERGYSTARcouldbefurtherexploredforMRIsrelatedtoancillaryequipment.
• X-rayo Lowpowerconsumptionmode:DataprovidedinFigure22showslow
powermodesvariedmorethandouble(0.08vs0.18kW)forthesameyearofX-rayMIE.Grapheddata(Figures19and20)aswellasthegraphsinAppendix3supportthisobservationfurther.COCIRvaluesforX-rayweresimilartothehigherX-raykWvaluesforlowerpowermode(0.15kW).
§ DatafromthisreportsuggeststhatX-raysmaygenerallybeabletogotolowerlowpowermodes.OpportunitiesforEnergyStarcertificationcouldbefurtherexploredforX-raysrelatedtolowerpowermode.
o StandbypowerconsumptionwasonlyavailableforoneoftheX-rayswithproposedvaluesat0.08-0.09kW.ThisishigherthantheCOCIRvalueof0.6kW.
§ DatafromthisreportsuggeststhatopportunitiesforEnergyStarcertificationcouldbefurtherexploredforX-raysrelatedtostandbypowermodes.
o Opportunitiestopowerdownequipmentwhennotinuse:§ X-rayequipmentisknowntotheindustryasoneoftheMIE
whichcouldbepowereddownwhennotinuse,iftheequipmentcanbebroughtbacktooperationallevelaccordingtotheneedsoftheuser.Manufacturesshouldbeencouragedtodevelopprotocolstoassistequipmentenduserstopowerdownequipmentasmuchaspossiblewhennotinuse.
§ Ancillaryequipment(suchascomputers)shouldbefurtherexaminedtoensurepoweringdownthesetypesofequipmentcanbeeasilydonetosaveenergywhentheequipmentisnotinuse.
§ DatafromthisreportsuggeststhatopportunitiesforEnergyStarcertificationcouldbefurtherexploredforX-raysrelatedtoancillaryequipment.
InitiatingENERGYSTARspecificationforMIEisnotaquickprocess,requiresgovernmentleadership,andmaytakeseveralyearstocomplete.TherearehoweverotheroptionstohelpencouragereductionofMIEenergyconsumptionthatcouldbeactedonmorequickly.Thesearesummarizedbelow.
37
5.2 Other opportunities to reduce MIE energy consumption in hospitals
1) ProvisionofpurchasingguidelinesforMIEwhichincludeenergyaspectsa. Includingenergyaspectsinpurchasingdecisionsisnotcurrentlypartof
thepurchasingpracticesinCanadianhospitals.CADTHreportsonMIEpurchasingpracticesandhowdecisionsaremadeandrevealsthatthereisgenerallynodirectmentionofenergycostswithinpurchasingcriteria,althoughinsomecasesoperationsandmaintenanceissuesarepartofthenewequipmentselectiondecisions.Convincingpurchaserstoincludeenergycriteriawouldrequireeducationandprovisionofsolidbusinesscaseinformationforthedecisionmakers.
b. GreenPublicProcurement(GPP)isbeingpromotedinEuropeformanytypesofhealthcareelectronicandelectricalequipment.SeeAppendix2forpartoftheGPPreportfromEuropewithspecificexamplesofhowtheprocesscanapplytoMIE.Thedocumentproposesspecificquestionstoaddtotenders,andtoindicatetovendersthatresponsestoenergyandotherenvironmentalquestionswillcarryaweightof15%ontheselection.ThebenefitsoftakingthisapproacharesummarizedintheirdocumentandprovidedinFigure25below.Energysavingsof50%forMRIandCTarepredicted,and80%forX-rays.
Figure25:BenefitsofapplyingGreenPublicProcurement(GPP)forMIE24
24 EU GPP Criteria for Electrical and Electronic Equipment used in the Health Care Sector (Health Care EEE) http://ec.europa.eu/environment/gpp/pdf/criteria/health/EN.pdf
38
2) DevelopenergybehaviourguidancedirectedatMIEusers
a. TurningMIEoffortolowpowermodeisanotherconsiderationthatcouldapplytoCT’sandX-rays(wheretheequipmentcouldbeturnedoffaccordingtomanufacturerreports)andMRIs(wheretheequipmentcouldbeturnedtolowestpowermode).Usinglowpowerornopowermodeswoulddependonhowlongtheequipmentisleftidle.Inthisstudy,thepercentageoftimetheequipmentwasusedvariedbetweenthedifferentsites.Forultrasoundhowever,energyconsumptioninready-to-scanmodeandscanmodearevirtuallythesame.25GuidingtheMIEusersonhowtodothisalongwithexpertsinMIEwouldbeessentialforenergyrelatedbehaviourchange.
b. AstudyinaDanishhospital26providedexamplesoftheircampaigntopurchasex-rayswhichweredesignedtobeturnedoffandeasilyre-booted.Theyfoundthatmanycompaniestheysurveyeddidnotprovidex-rayswiththiscapability.
c. TheCADTH2016reportprovidestheresultsofasurveythataskedMIEusersfortheaveragenumberofhourstheequipmentisusedinaweekandperday.TheresponsestothesequestionsfortheCTsareprovidedinFigure26below.Thereareasignificantnumberofunitsthatareusedlessthan50%ofthetime.ThisrevealsanopportunitytoconsiderthequestionofturningofftheCTswhennotinuseforalongperiodoftime.InmostcasestheCTsarelikelykeptin‘readymode’toavoidasequenceofdiagnosticsthattheunithastorunthrough.Oneofthetechniciansduringthisstudyprovidedanotherreasonhospitalsmaykeeptheunitson:theMinistryofHealthandLongTermCareprovidesfundingaccordingtotheamountofruntime.Thisstatementshouldbefurtherexploredtodetermineifitisthecase,andifthepersonnelthatrunMIEneedtobebetterinformedonenergyusage.
d. TheCOCIRgroupdevelopedpromotionalmaterialsforEuropeanMIEuserstohelppromoteturningoffCTs,andtousethelowestpowermodeforMRIswhennotinuse(seeSection2.2).Inourstudyonetechnicianreportedthatittakes6hourstopowertheCTbackup.However,ifthemanufacturersarepromotingturningoffCTswhennotinuse,thentheremustbesomeunitsonthemarketwherethisisaviableoption.Newpurchasescouldaskthisquestionofpotentialvenders.Equipmentmanufacturersshouldbeencouragedtoprovidesettingsthathelpmakeiteasyfortheusertakeenergysavingsteps.
25 http://www.cocir.org/fileadmin/6_Initiatives_SRI/SRI_Status_Report/SRI_Status_Report_2015_-_21_September_2016.pdf 26Energy efficiency in hospitals and laboratories (6-337-11) Anders Hjorth Jensen, Danish Energy Saving Trust, Denmark Peter Maagøe Petersen, Viegand & Maagøe ApS, Denmark http://ec.europa.eu/environment/gpp/pdf/criteria/health/EN.pdf
39
Figure26:AveragehoursofoperationofCTunitsinatypicalweekandinatypicalday(CanadiansurveyresultsfromCADTH)27
3) OptimizingenergyconsumptionofcoolingrequirementsforMIEequipment
a. Coolingsystemequipmentrequiredtoensurethatcriticalenvironmentalrequirementsaremetcanconsumesignificantenergythrough,forexample,theairhandlingunits(AHUS).OptimizingthesesystemsalongwiththeMIEenergyuseandpowermodecanresultinenergysavings.
b. AncillaryequipmentwithineachoftheMIEroomsshouldalsobeconsideredforenergyefficiencyopportunities.AstudyataNorwegianhospital28revealedtheirresults:
i. DataofenergyconsumedbyMIEfromAHUSshoweddirectannualelectricalenergyconsumptionofabout1774.313kBTU/year(520.000kWh/year).Indirectcoolingutilityconsumptionmeansthatthetotalenergyisapproximately2132.588kBTU/year(625000kWh/year),assuming80%recyclingofwasteheat.Dividingby
27 CADTH ENVIRONMENTAL SCAN. Diagnostic Imaging Equipment Replacement and Upgrade in Canada January 2016. Project # ES0303 28 Equipment and Energy Usage in a Large Teaching Hospital in Norway Tarald Rohde1* and Robert Martinez2 1SINTEF, Technology and Society, Hospital Planning, Oslo, Norway 2Norconsult as, Sandvika, Norway Submitted October 2014. Journal of Healthcare Engineering · Vol. 6 · No. 3 · 2015 pg 428
40
totalhospitalareaprovidestotalspecificenergyintensityforlargeMIEatabout1.6kBTU/ft2peryear(5.2kWh/m2peryear).
ii. Hospitaladministratorscanconsiderenergymonitoringsystems(EMS),tiedtothecentralbuildingautomationsystem(BAS)formedicalequipment,andnetworkpowermanagementsystems(PMS)shouldbeimplementedforICTequipment.Hospitalclinicalstaffshouldclassifyequipmentwhichisnon-criticalandcanbepartofautomaticshut-offroutines.Automaticallytimedelectricalpowercircuitsforsuchnon-criticalequipmentshouldbeintroduced,startinginlaboratoryareas.Automationofelectricalsockets,markedwithseparatecolorandwithLEDstatusindicator,canprovidegreatsavingsinmanyareas.Hospitaltopadministratorsshouldestablishenergymanagementpractices,withclearaccountabilityandsupport...Inpractice,thissimplymeansroutinesforturningoffequipmentoutsideworkinghours,andenforcementofsuchpractice.Anothersuggestionistoestablishhierarchywhereequipmentsuchasprinterssubordinatetoothermainequipmentwillbepowereddownwhenthemaindeviceispowereddown.Thiswillreduce“phantomloads”fromstandbyofICTequipment,whichisabout5%oftheequipment’stotalenergyuse.
c. AnotherstudylookedatancillaryandtotalroomenergyconsumptionoftwodifferentMIEroomsinUShospitalsandfoundthatforCTs,ofthedirectenergyuse,idleenergywasthelargestdirectenergyconsumer,followedbytheheating,ventilationandairconditioning(HVAC)systemaspresentedinFigure27below.TwogeneralmedicalandsurgicalhospitalsinWitchita,Kansas,theWeselyHospitalMedicalCenterandVAMedicalCenter,lookedatthemonthlyenergyconsumptionoftheMIE‘rooms’andrelatedenergyaspectsfromtwodifferentmanufacturers.Ofnotearethefollowingobservations:
i. Fordirectenergyuse,idleenergywasthelargestdirectenergyconsumer,followedbytheheating,ventilationandairconditioning(HVAC)system
ii. Idleenergyconsumptionbetweenthetwovendersdifferedbyabout50%
iii. Inthehospitalwhichhadlowerenergyconsumptionduetoidleenergy,muchlowerHVACenergy(80%lower)wasused.
iv. Ancillaryenergyusevariedsignificantlybetweenthetwomanufacturers(90%).
v. Standbyenergyconsumptionwasamuchlowercostforthesetwohospitals,althoughthisdependsontheusefrequency,andiftheequipmentgenerallygoesmorereadilytolowpowermode.
vi. Lightingintheseareasisalsoaconsideration.LEDlightsintheseareascanreduceanaddedheatload.
vii. Fromamoreholisticapproach,energyusecalculatedaspartofconsumableandreusablematerialscanalsobesignificant.
41
Figure27:ComparisonofenergyconsumptioninCTequipmentrooms29
4) DevelopmentofaBusinessCaseforMIEpurchasingpersonnel
a. CostinformationonMIEandancillaryequipmentcouldbedevelopedintoaBusinessCaseforequipmentpurchasersandhospitalpurchasingagentssothatenergyoperatingcostscanbeconsideredaspartofthenewequipmentevaluation.Figure23providesasummaryofthecostdatarelatedtotheMIEtimespentinidleandreadytoscanmode.
i. MRIsevaluatedinthisstudycostmoretooperatewhentherewaslesstimespentinidlepowermode.Averagecoststooperaterangedfrom$20,000to$30,000peryearjustfortheMRI.Addingintheancillaryenergyfromtheequipmentandcoolingcanbringthisamountupconsiderably.
ii. CTsevaluatedinthisstudycostmoretooperatewhentherewaslesstimespentinidlepowermode.Averagecoststooperaterangedfrom$3,000to$6,000peryear,justfortheCTequipment.Addingintheancillaryenergyfromtheequipmentandcoolingcan
29 Life Cycle for Engineering the Healthcare Service Delivery of Imaging. Jan Twomey, Professor Industrial and Manufacturing Engineering, Wichita University http://emse.mst.edu/media/academic/emse/documents/EMSEGraduateSeminar-DrJanetTwomey.pdf
42
bringthisamountupconsiderably.Aswell,manyhospitalshavemorethanoneCT.
iii. X-raysevaluatedinthisstudycost$100peryearwhennoscanninghastakenplace,andapproximately$400whentheyareusedforscanningandspendmoretimeinstandbymode.ThesecostsarejustfortheX-rayequipment.Addingintheancillaryenergyfromtheequipmentandcoolingcanbringthisamountupconsiderably.Aswell,manyhospitalshavemorethanoneX-raywhichbringsthecontributionofthetotaloperatingexpensemultifold.
43
6. Conclusions ThisstudyinvestigatedtheenergyconsumptionofthreetypesofMIEwhichconstitutesomeofthelargerpowerconsumptionmedicalimagingequipmentinhospitals.Lowpowerandstand-byconsumptioninparticularwereassessedtodetermineifMIEs,particularlyMRIsandCTsandX-rays,couldbecandidatesforENERGYSTARstandarddevelopment.Resultsfromthisstudyshowedthattherewerevariancesinlowpowermodesgreaterthan25%insomecases,butwhencomparedtovaluesreportedintheliterature,thevariationswereevengreater.Theresultsshowthatnon-scanningenergyconsumption,eitherlowpowerorstand-bymodes,haveinsomecasesrepresentedupto80%ofthetotalenergyconsumptionbyMIEinsomehospitals,whileinotherhospitalstheequipmentisusedonamuchmoreregularbasis,sometimesaroundtheclock.Encouragingmanufacturerstomakeequipmentwheretheuserwillbecomfortableinmakingthedecisiontoturnthepowerdownshouldalsobeaconsideration.Helpingmakethecaseforaddressingenergyefficiencyinthelowpowerandstand-bymodesinMIEisalsothefactthatthereisacontinualgrowthinMIEproductsinNorthAmerica,andthatpurchasingdecisionsforMIEsshouldtakeintoaccountoperatingcostsrelatedtoenergyconsumption.
Recommendationsinclude:1) DevelopmentofENERGYSTARspecificationforMIEs.
a. Thisreportidentifiedthattherearesignificantdifferencesinthelowpowerandscanningpowermodeswithintheequipmentmeasuredandintheenergyconsumptionvaluesreportedliterature.
b. AlongwiththedirectenergyuseofMIE,ancillaryenergyconsumptionofallrelatedancillaryequipmentaccompanyingtheMIEshouldalsobeassessedforreductionofenergyuse.
c. ENERGYSTARspecificationdevelopmentisnotaquickprocess,requiringgovernmentleadership,andmaytakeseveralyearstocomplete.TherearehoweverotheroptionstohelpencouragereductionofMIEenergyconsumptionthatcouldbeactedonmorequicklyandincludethefollowing:
2) ProvisionofpurchasingguidelinesforMIEwhichincludeenergyaspectsa. Includingenergyaspectsinpurchasingdecisionsisnotcurrentlypartof
thepurchasingpracticesinCanadianhospitals.Convincingpurchaserstoincludeenergycriteriawouldrequireeducation,guidanceandprovisionofsolidbusinesscaseinformationforthedecisionmakers.
44
b. TheGreenPublicProcurement(GPP)initiativepromotedinEuropeestimatespossibleenergysavingsof50%forMRIandCT,and80%forX-rays.
3) DevelopenergybehaviourguidancedirectedatMIEusersa. TurningMIEoffortolowpowermodeisanotherconsiderationthat
couldapplytoCT’sandX-rays(whichcanbeturnedoff)andMRIs(wheretheequipmentcouldbeturnedtolowestpowermode).GuidingtheMIEusersonhowtodothisalongwithexpertsinMIEwouldbeessentialforenergyrelatedbehaviourchange.
4) OptimizingenergyconsumptionofcoolingrequirementsforMIEequipmenta. Coolingsystemequipmentarerequiredtoensurecriticalenvironmental
requirementsaremetforMIEbutthesecanconsumesignificantenergythrough,forexample,theairhandlingunits.OptimizingthesesystemsalongwiththeMIEenergyuseandpowermodecanresultinenergysavings.
5) DevelopmentofaBusinessCaseforMIEpurchasingpersonnela. CostinformationonMIEandancillaryequipmentcouldbedevelopedinto
aBusinessCaseforequipmentpurchasersandhospitalpurchasingagentssothatenergyoperatingcostscanbeconsideredaspartofthenewequipmentevaluation.
i. MRIs:Averagecoststooperaterangedfrom$20,000to$30,000peryearjustfortheMRI.Addingintheancillaryenergyfromtheequipmentandcoolingcanbringthisamountupconsiderably.
ii. CTs:Averagecoststooperaterangedfrom$3,000to$6,000peryear,justfortheCTequipment.Addingintheancillaryenergyfromtheequipmentandcoolingcanbringthisamountupconsiderably.Aswell,manyhospitalshavemorethanoneCT.
iii. X-rays:Averagecoststooperaterangedfrom$100peryearwhennoscanninghastakenplace,andapproximately$400whentheyarebeingused.ThesecostsarejustfortheX-rayequipment.Addingintheancillaryenergyfromtheequipmentandcoolingcanbringthisamountupconsiderably.Aswell,manyhospitalshavemorethanoneX-raywhichbringsthecontributionofthetotaloperatingexpensemultifold.
45
Appendix 1: Detailed testing guidance for different scan modes
ENERGY STAR® Program Requirements Product Specification for Medical Imaging Equipment Final Draft Test Method For Determining Medical Imaging Equipment Energy Use Rev. Aug - 2014
ENERGY STAR Program Requirements for Medical Imaging Equipment – Final Draft Test Method (Rev. Aug-2014) Page 1 of 5
1 OVERVIEW 1
The following test method shall be used for determining product compliance with requirements in the 2 ENERGY STAR Eligibility Criteria for Medical Imaging Equipment (MIE). 3
2 APPLICABILITY 4
The proposed test method shall be used to determine the energy efficiency of all products under the 5 ENERGY STAR Product Specification for Medical Imaging Equipment. Medical Imaging Equipment and 6 all products identified below are defined in this test method in Section 3.B). 7
Note: A proposed Scope is included in this document for completeness. Upon development of the 8 Version 1.0 Draft 1 specification and eligibility criteria, the U.S. Environmental Protection Agency (EPA) 9 will further refine and define the scope of included products for the program. 10
2.1 Products Included in Scope 11
A) Computed Tomography (CT) 12
B) General Radiography (X-ray) 13
C) Magnetic Resonance Imaging (MRI) 14
D) Mammography Equipment 15
E) Nuclear Imaging 16
F) Ultrasound Imaging/Sonography 17
2.2 Products excluded from scope 18
A) Endoscopy 19
B) Photoacoustic Imaging 20
C) Thermography 21
3 DEFINITIONS 22
Note: For completeness, the acronyms and definitions below have been included in the test method. The 23 entire definitions section will be moved to the eligibility criteria upon development of the Version 1.0 Draft 24 1 specification. 25
A) Acronyms and Units: 26
1) ac: Alternating Current 27
2) CT: Computed Tomography 28
46
6.2 Ready-to-scan Mode Testing
A) Ensure that the power meter is on and functioning.
B) Prescribe a patient and execute any scan to ensure that the UUT is functioning.
C) After the scan completes, wait 5 minutes, and then record the average power draw (rate of energy 152 consumption), for a period of 12 minutes. Record this value, in kW.
Note: The preliminary test method has been revised to include a waiting period of 5 minutes after completing a scan and before beginning the measurement of average power. This waiting period is included to allow any data processing that may occur after the scan to complete.
6.3 Low-power Mode Testing
A) Ensure that the power meter is on and functioning.
B) Select the Low-power mode as specified in the user manual.
C) Wait to ensure that all applicable system elements of the UUT have adapted to this mode.
D) Measure the average power draw (rate of energy consumption), for a period of at least 10 minutes. If the system has a variable power usage in this mode, the measurement duration shall be amended to one complete power usage cycle, which shall be taken to be the cycle from minimum to maximum usage.
E) Record this value, in kW.
Note: The test methods for Ready-to-scan and Low-power modes are primarily based on COCIR Computed Tomography Measurement of Energy Consumption (Revision 0), and COCIR Magnetic Resonance Equipment Measurement of Energy Consumption (Revision 1).
This test method only includes test methods for Ready-to-scan and Low-power modes. DOE and EPA realize that there are many complexities associated with testing in Scan (active) mode, such as setting proper scan protocols (for abdomen, chest, head, etc.) and specifying phantom materials to use. Furthermore, energy consumption in Low-power and Ready-to-scan modes can represent the majority of total annual energy consumption.
47
Appendix 2: EU Green Public Procurement (GPP) for healthcare electrical and electronic equipment The following information is from the EU GPP Criteria for Electrical and Electronic Equipment used in the Health Care Sector (Health Care EEE)http://ec.europa.eu/environment/gpp/pdf/criteria/health/EN.pdf Green Public Procurement (GPP) is a voluntary instrument. This document provides the EU GPP criteria developed for electrical and electronic equipment used in the health care sector. Detailed information about the health care EEE product group, the reasons for selecting these criteria, information about related legislation and other sources can be found in the Technical Background Report. EU GPP criteria are usually presented in two sets, core and comprehensive criteria: • The core criteria are those suitable for use by any contracting authority across the Member States and address the key environmental impacts. They are designed to be used with minimum additional verification effort or cost increases. • The comprehensive criteria are for those who wish to purchase the best products available on the market. These may require additional verification effort or a slight increase in cost compared to other products with the same functionality. Since this is a new product group, mainly core criteria have been set. The comprehensive criteria are at the end of the document (nr. 17 and 18). The criteria have been developed to encourage the purchase of Healthcare EEE with reduced environmental impacts while always giving priority to the safety and welfare of patients as well as that of medical staff, technicians and maintenance personnel. Contracting authorities will have to indicate in the contract notice and tender documents how many points will be awarded for each award criterion. Environmental award criteria should, altogether, account for at least 15% of the total points available TheEU’sGreenPurchasingGuideline30forenergyefficiencylistsbenefitstoincludingenergyandotherenvironmentalcriteriainpurchasingtenders.FortheMIEthesearesummarizedintheEUcontextasfollows(pg23):
MIE Environmental Benefit Economic Benefit (Euros)
CT • Energy savings of 50 % during thorax examinations • Energy savings of 80 % during cardiac examinations • (Energy savings of 50 % in daily energy consumption) • 33,000kWh per machine annually, 15 tons of CO2 emissions, equivalent to the annual CO2 emissions of 4 cars
• Annual savings of up to € 3700 per CT system
MRI •50% less energy usage (business as usual: operating an MRI can produce about 90 tons of CO2 annually) • Reduces annual electricity usage by about 60,000 kWh, equivalent to the annual electricity consumption of 5 households, 27 metric tons of CO2, equivalent to
• Annual savings of up to € 6700 per MRI
30EU GPP Criteria for Electrical and Electronic Equipment used in the Health Care Sector (Health Care EEE)http://ec.europa.eu/environment/gpp/pdf/criteria/health/EN.pdf
48
the annual emissions of 7 cars
Mammography • 50% reduction in energy use
Ultrasound • Energy savings of 90%
• 50% reduction in energy use
X-ray • 80 % more energy efficient
CT
49
50
MRI
51
X-RayandMamography
Ultrasound(pg12)
forbothUltrasoundandX-Ray/mammography
52
AutomaticLowPowerModes
53
54
Appendix 3: MIE Energy Measurement Data
55
Table of Contents
APPENDIX1:MRIENERGYCONSUMPTIONDATA 56
APPENDIX1.1MRIENERGYCONSUMPTIONDATASITE#1 56APPENDIX1.2MRIENERGYCONSUMPTIONDATASITE#2 75
APPENDIX2:CTDATA 95
APPENDIX2.1CTENERGYCONSUMPTIONDATASITE#1 96APPENDIX2.2CT#2ENERGYCONSUMPTIONSITE#1 105APPENDIX2.3CTENERGYCONSUMPTIONDATASITE#2 111APPENDIX2.4CTENERGYCONSUMPTIONDATASITE#3 132
APPENDIX3:X-RAYDATA 133
APPENDIX3.1.1:X-RAYDATASITE#1CTENERGYCONSUMPTIONDATASITE#3 133APPENDIX3.1.2X-RAYSITE1 141
56
Appendix 3.1: MRI Energy Consumption Data Appendix 3.1.1 MRI Energy Consumption Data Site #1
57
Table1–MRISite#1–Siemens(MagnetomAera2013).Overviewofthepowerconsumption(kW)overthe11-dayperiodofmonitoring.
Summary of power consumption* (kW) at six minute interval over the monitoring period for BC MRI* Average kW reading was used for this analysis.
kW Range (kW) Count of kW Average of kW (kW)
Energy consumption of each kW range over sampling
period (kWmin)
Energy consumption of each kW range over sampling period (kWh)
Energy consumption Percentage of each kW range
Estimated Energy Consumption
(kWh) over One Year
Estimated annual cost @$0.15 per
kWh
[0,10) 0.0 NA 0.0 0.0 0.0% 0.0 -$ [10,12) 1.0 10.8 64.5 1.1 0.0% 26.9 4.0$ [12,14) 3.0 13.1 235.7 3.9 0.1% 98.2 14.7$ [14,16) 1742.0 14.5 151772.5 2529.5 33.2% 63256.6 9,488.5$ [16,18) 127.0 17.0 12983.8 216.4 2.8% 5411.5 811.7$ [18,20) 81.0 18.9 9180.5 153.0 2.0% 3826.3 573.9$ [20,22) 112.0 21.2 14245.5 237.4 3.1% 5937.3 890.6$ [22,24) 137.0 23.0 18942.5 315.7 4.1% 7895.0 1,184.2$ [24,26) 145.0 25.1 21807.2 363.5 4.8% 9088.9 1,363.3$ [26,28) 156.0 27.0 25264.6 421.1 5.5% 10529.9 1,579.5$ [28,30) 164.0 29.0 28547.4 475.8 6.2% 11898.2 1,784.7$ [30,32) 205.0 31.0 38164.5 636.1 8.3% 15906.4 2,386.0$ [32,34) 199.0 33.1 39482.5 658.0 8.6% 16455.7 2,468.4$ [34,36) 184.0 34.9 38483.4 641.4 8.4% 16039.3 2,405.9$ [36,38) 95.0 37.1 21124.5 352.1 4.6% 8804.4 1,320.7$ [38,40) 70.0 39.0 16380.1 273.0 3.6% 6827.0 1,024.0$ [40,42) 42.0 40.8 10285.3 171.4 2.2% 4286.8 643.0$ [42,44) 27.0 43.0 6973.8 116.2 1.5% 2906.6 436.0$ [44,46) 9.0 44.8 2421.3 40.4 0.5% 1009.2 151.4$ [46,48) 2.0 47.1 565.5 9.4 0.1% 235.7 35.4$ [48,50) 2.0 49.4 593.2 9.9 0.1% 247.2 37.1$ [50,9999) 0.0 NA 0.0 0.0 0.0% 0.0 -$ Grand Total 3503.0 21.8 457518.3 7625.3 100% 190687.0 28,603.1$
58
Figure1–EnergyConsumptionPercentageofeachpowerrange
Forexample,theenergyconsumptionbypowerrangethatfallinto14-16kWcontributedto33.2%ofthetotalenergyconsumption over the monitoring period.
0%
5%
10%
15%
20%
25%
30%
35%
[0,10)
[10,12)
[12,14)
[14,16)
[16,18)
[18,20)
[20,22)
[22,24)
[24,26)
[26,28)
[28,30)
[30,32)
[32,34)
[34,36)
[36,38)
[38,40)
[40,42)
[42,44)
[44,46)
[46,48)
[48,50)
[50,9999)
Power(kW)
EnergyconsumptionPercentageofeachkWrange
59
Figure2–Timeseriesofpowerconsumptionforeachday
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
Appendix 3.1.2 MRI Energy Consumption Data Site #2 Table2:MRISite#2:Siemens(Advento2013).Powerconsumption(kW)overthe1-weekperiodofmonitoring
kWminute Range
(kW)Count of kWminute
Sum of kWminute
(kW)
Percentage of
each range
Energy
Consumption
(kWh) over
sampling period
Estimated Energy
Consumption
(kWh) over One
Year
Estimated
annual cost
@$0.15 per
kWh
[0,13) 0.0 0.0 0.0% 0.0 0.0 -$ [13,14) 8837.0 122480.8 80.9% 2041.3 105916.3 15,887.4$ [14,15) 103.0 1456.2 1.0% 24.3 1259.3 188.9$ [15,16) 6.0 93.3 0.1% 1.6 80.7 12.1$ [16,17) 16.0 263.8 0.2% 4.4 228.1 34.2$ [17,18) 63.0 1120.5 0.7% 18.7 969.0 145.3$ [18,19) 374.0 6882.6 4.5% 114.7 5951.7 892.8$ [19,20) 99.0 1930.7 1.3% 32.2 1669.6 250.4$ [20,21) 94.0 1925.2 1.3% 32.1 1664.8 249.7$ [21,22) 71.0 1518.9 1.0% 25.3 1313.4 197.0$ [22,23) 73.0 1646.6 1.1% 27.4 1423.9 213.6$ [23,24) 73.0 1712.8 1.1% 28.5 1481.2 222.2$ [24,25) 42.0 1027.3 0.7% 17.1 888.4 133.3$ [25,30) 123.0 3385.7 2.2% 56.4 2927.8 439.2$ [30,40) 102.0 3415.3 2.3% 56.9 2953.4 443.0$ [40,50) 39.0 1685.6 1.1% 28.1 1457.7 218.6$ [50,60) 15.0 823.6 0.5% 13.7 712.2 106.8$ [60,9999) 0.0 0.0 0.0% 0.0 0.0 -$ Grand Total 10130.0 151368.9 100% 2522.8 130897.5 19,634.6$
Summary of power consumption (kW) at one minute interval over the entire monitoring period
76
Figure1-Timeseriesofthepowerconsumption(kW)forthesamplingperiod
0
10
20
30
40
50
60
:05
:06
:07
:08
:09
:10
:11
:12
:13
:14
:15
:16
:17
:18
:19
:20
:21
:22
:23
:24
:25
:26
:27
:28
:29
:30
:31
:32
:33
:34
:35
:36
:37
:38
:39
:40
:41
:42
:43
:44
:45
:46
:47
:48
:49
:50
:51
:52
:53
:54
:55
:56
:57
:58
:59
:00
8AM
27-Feb 28-Feb 1-Mar 2-Mar 3-Mar 4-Mar 5-Mar 6-Mar
Feb Mar
PowerConsumption(kW)
77
Figure2-Timeseriesofthepowerconsumption(kW)foreachsingledayoverlapped
0
10
20
30
40
50
60:0
0:2
8:5
6:2
4:5
2:2
0:4
8:1
6:4
4:1
2:4
0:0
8:3
6:0
4:3
2:0
0:2
8:5
6:2
4:5
2:2
0:4
8:1
6:4
4:1
2:4
0:0
8:3
6:0
4:3
2:0
0:2
8:5
6:2
4:5
2:2
0:4
8:1
6:4
4:1
2:4
0:0
8:3
6:0
4:3
2:0
0:2
8:5
6:2
4:5
2:2
0:4
8
12 AM 1 AM 2 AM 3 AM 4 AM 5 AM 6 AM 7 AM 8 AM 9 AM 10 AM11 AM12 PM 1 PM 2 PM 3 PM 4 PM 5 PM 6 PM 7 PM 8 PM 9 PM 10 PM11 PM
Pow
er C
onsu
mpt
ion
(kW
)
27-Feb 28-Feb 1-Mar 2-Mar 3-Mar 4-Mar 5-Mar 6-Mar
78
Figure3-Timeseriesofthepowerconsumption(kW)foreachminuteaveragedoverthesamplingperiod
10
12
14
16
18
20
22
24
26
28
30:0
0:2
8:5
6:2
4:5
2:2
0:4
8:1
6:4
4:1
2:4
0:0
8:3
6:0
4:3
2:0
0:2
8:5
6:2
4:5
2:2
0:4
8:1
6:4
4:1
2:4
0:0
8:3
6:0
4:3
2:0
0:2
8:5
6:2
4:5
2:2
0:4
8:1
6:4
4:1
2:4
0:0
8:3
6:0
4:3
2:0
0:2
8:5
6:2
4:5
2:2
0:4
8
12 AM 1 AM 2 AM 3 AM 4 AM 5 AM 6 AM 7 AM 8 AM 9 AM 10 AM11 AM12 PM 1 PM 2 PM 3 PM 4 PM 5 PM 6 PM 7 PM 8 PM 9 PM 10 PM11 PM
Aver
age
pow
er co
nsum
ptio
n (k
W) o
ver s
ampl
ing
perio
d
79
Figure4-Frequencycountofthepowerconsumption(kW)atoneminuteintervaloversamplingperiod
Power Range
(kW)
Count of kWminute
12-14 8837 14-16 109 16-18 79 18-20 473 20-22 165 22-24 146 24-26 56 26-28 76 28-30 33 30-32 48 32-34 11 34-36 26 36-38 7 38-40 10 40-42 14 42-44 10 44-46 9 46-48 6 50-52 1 52-54 1 54-56 11 56-58 2
Grand Total 10130
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
12-1
4
14-1
6
16-1
8
18-2
0
20-2
2
22-2
4
24-2
6
26-2
8
28-3
0
30-3
2
32-3
4
34-3
6
36-3
8
38-4
0
40-4
2
42-4
4
44-4
6
46-4
8
50-5
2
52-5
4
54-5
6
56-5
8
Coun
t
kWminute groups based on value (kW)
80
Figure5–EnergyConsumption(kWminute)ofeachpowerrange
Forexample,theenergyconsumptionbypowervaluesthatfallinto12-14kWis122480.84 kWminute over the monitoring period.
Power Range (kW)
Energy Consumption (kWminute)
12-14 122480.84 14-16 1549.55 16-18 1384.36 18-20 8813.24 20-22 3444.05 22-24 3359.42 24-26 1383.99 26-28 2066.02 28-30 962.99 30-32 1490.33 32-34 366.21 34-36 909.47 36-38 259.06 38-40 390.18 40-42 574.05 42-44 426.66 44-46 404.53 46-48 280.39 50-52 51.24 52-54 52.96 54-56 606.33 56-58 113.02
Grand Total 151368.89
0
20000
40000
60000
80000
100000
120000
140000
12-1
4
14-1
6
16-1
8
18-2
0
20-2
2
22-2
4
24-2
6
26-2
8
28-3
0
30-3
2
32-3
4
34-3
6
36-3
8
38-4
0
40-4
2
42-4
4
44-4
6
46-4
8
50-5
2
52-5
4
54-5
6
56-5
8Tota
l ene
rgy
cons
umpt
ion
over
the
sam
plin
g pe
riod
(kW
min
ute)
Power consumption groups based on value (kW)
81
Figure6-EnergyConsumption(kWminute)percentageofeachpowerrange
Power Range (kW)
Percentage of energy consumption
12-14 80.92% 14-16 1.02% 16-18 0.91% 18-20 5.82% 20-22 2.28% 22-24 2.22% 24-26 0.91% 26-28 1.36% 28-30 0.64% 30-32 0.98% 32-34 0.24% 34-36 0.60% 36-38 0.17% 38-40 0.26% 40-42 0.38% 42-44 0.28% 44-46 0.27% 46-48 0.19% 50-52 0.03% 52-54 0.03% 54-56 0.40% 56-58 0.07% Grand Total 100.00%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
12-14
14-16
16-18
18-20
20-22
22-24
24-26
26-28
28-30
30-32
32-34
34-36
36-38
38-40
40-42
42-44
44-46
46-48
50-52
52-54
54-56
56-58
Energyconsum
ptionpercentage
Powerconsumptiongroupsbasedonvalue(kW)
82
Figure7–Energyconsumptionpercentageofdifferentpowergroups
0%10%20%30%40%50%60%70%80%90%
[0,13)[13,14)[14,15)[15,16)[16,17)[17,18)[18,19)[19,20)[20,21)[21,22)[22,23)[23,24)[24,25)[25,30)[30,40)[40,50)[50,60)
[60,9999)
Energyconsum
ptionp
ercentage
Powerconsumptiongroupsbasedonvalue(kW)
83
Figure8-Timeseriesoftheenergyconsumption(kWminute)foreachminuteovereachhour
84
85
86
87
88
89
90
91
92
93
94
95
Appendix 3.2: CT Data
96
Appendix 3.2.1 CT Energy Consumption Data Site #1
Table1–CTSite#1:Siemens(Flash128scanmode,2016).Powerconsumption(kW)forthe1-weekperiodofmonitoring.
Figure1–EnergyConsumptionPercentageofeachpowerrange
Summary of power consumption* (kW) at six minute interval over the monitoring period for BC CT
* Average kW reading was used for this analysis.
kW Range (kW)
Count of kW
Average of kW (kW)
Energy consumption of each kW range
over sampling period (kWmin)
Energy consumption of each kW range
over sampling period (kWh)
Energy consumption
Percentage of each kW range
Estimated Energy Consumption over One Year
(kWh)
Estimated annual cost
@$0.15 per kWh
[0,1) 0.0 NA 0.0 0.0 0.0% 0.0 -$ [1,2) 284.0 1.9 3315.4 55.3 10.8% 3418.4 512.8$ [2,3) 6.0 2.5 91.2 1.5 0.3% 94.1 14.1$ [3,4) 929.0 3.6 20206.8 336.8 65.6% 20834.7 3,125.2$ [4,5) 62.0 4.4 1639.8 27.3 5.3% 1690.7 253.6$ [5,6) 41.0 5.6 1368.6 22.8 4.4% 1411.2 211.7$ [6,7) 60.0 6.4 2306.2 38.4 7.5% 2377.9 356.7$ [7,8) 14.0 7.3 613.6 10.2 2.0% 632.6 94.9$ [8,9) 9.0 8.4 451.5 7.5 1.5% 465.5 69.8$ [9,10) 1.0 9.2 54.9 0.9 0.2% 56.6 8.5$ [10,11) 2.0 10.5 126.0 2.1 0.4% 129.9 19.5$ [11,12) 0.0 NA 0.0 0.0 0.0% 0.0 -$ [12,13) 3.0 12.4 223.6 3.7 0.7% 230.5 34.6$ [13,14) 2.0 13.6 162.7 2.7 0.5% 167.8 25.2$ [14,15) 3.0 14.3 256.7 4.3 0.8% 264.7 39.7$ [15,9999) 0.0 NA 0.0 0.0 0.0% 0.0 -$ Grand Total 1416.0 3.6 30817.0 513.6 100% 31774.6 4,766.2$
97
Forexample,theenergyconsumptionbypowerrangethatfallinto3-4kWcontributedto65.6%ofthetotalenergy
consumption over the monitoring period.
0%
10%
20%
30%
40%
50%
60%
70%
[0,1)
[1,2)
[2,3)
[3,4)
[4,5)
[5,6)
[6,7)
[7,8)
[8,9)
[9,10)
[10,11)
[11,12)
[12,13)
[13,14)
[14,15)
[15,9999)
Power(kW)
EnergyconsumptionpercentageofeachkWrange
98
Figure2–Timeseriesofpowerconsumptionforeachday
99
100
101
102
103
104
105
Appendix 3.2.2 CT #2 Energy Consumption Site #1
Table3:CT:Siemens(Edge64scanmode,2016).Powerconsumption(kW)over1-weekperiodofmonitoring
Summary of power consumption* (kW) at three minutes interval over the monitoring period for BC CT#2
* Average kW reading was used for this analysis.
kW Range (kW)
Count of kW
Frequency Percentage
Average of kW (kW)
Energy consumption of each kW range
over sampling period (kWmin)
Energy consumption of each kW range
over sampling period (kWh)
Energy consumption
Percentage of each kW range
Estimated Energy Consumption over One Year
(kWh)
Estimated annual cost
@$0.15 per kWh
[0,0.5) 5 0.3% 0.31 4.6 0.1 0.0% 7.6 1.1$ [0.5,1) 230 12.8% 0.96 664.2 11.1 5.0% 1083.5 162.5$ [1,2) 6 0.3% 1.24 22.3 0.4 0.2% 36.3 5.4$ [2,3) 1385 77.4% 2.34 9730.1 162.2 73.3% 15872.5 2,380.9$ [3,4) 47 2.6% 3.45 486.4 8.1 3.7% 793.4 119.0$ [4,5) 23 1.3% 4.46 307.4 5.1 2.3% 501.5 75.2$ [5,6) 24 1.3% 5.44 391.4 6.5 2.9% 638.4 95.8$ [6,7) 24 1.3% 6.37 458.5 7.6 3.5% 747.9 112.2$ [7,8) 30 1.7% 7.45 670.4 11.2 5.1% 1093.6 164.0$ [8,9) 4 0.2% 8.36 100.3 1.7 0.8% 163.6 24.5$ [9,10) 3 0.2% 9.16 82.5 1.4 0.6% 134.6 20.2$ [10,11) 4 0.2% 10.55 126.6 2.1 1.0% 206.5 31.0$ [11,12) 0 0.0% NA 0.0 0.0 0.0% 0.0 -$ [12,13) 0 0.0% NA 0.0 0.0 0.0% 0.0 -$ [13,14) 1 0.1% 13.24 39.7 0.7 0.3% 64.8 9.7$ [14,15) 0 0.0% NA 0.0 0.0 0.0% 0.0 -$ [15,16) 3 0.2% 15.46 139.1 2.3 1.0% 227.0 34.0$ [16,17) 1 0.1% 16.68 50.1 0.8 0.4% 81.7 12.2$ [17,9999) 0 0.0% NA 0.0 0.0 0.0% 0.0 -$ Grand Total 1790 1.0 2.5 13273.5 221.2 100% 21652.8 3,247.9$
106
Figure1–EnergyConsumptionPercentageofeachpowerrange
Forexample,theenergyconsumptionbypowerrangethatfallinto2-3kWcontributedto73.3%ofthetotalenergy
consumption over the monitoring period.
0%
10%
20%
30%
40%
50%
60%
70%
80%
[0,0.5)
[0.5,1)
[1,2)
[2,3)
[3,4)
[4,5)
[5,6)
[6,7)
[7,8)
[8,9)
[9,10)
[10,11)
[11,12)
[12,13)
[13,14)
[14,15)
[15,16)
[16,17)
[17,9999)
Power(kW)
EnergyconsumptionPercentageofeachkWrange
107
Figure2–Timeseriesofpowerconsumptionforeachday
108
109
110
111
Appendix 3.2.3 CT Energy Consumption Data Site #2
Table1:CT:GE(LightspeedDiscoveryHD750,2012).Powerconsumption(kW)overthe8daysofmonitoring:
kWminute Range
(kW)Count of kWminute
Sum of kWminute
(kW)
Percentage of
each range
Energy
Consumption
(kWh) over
sampling period
Estimated Energy
Consumption
(kWh) over One
Year
Estimated
annual cost
@$0.15 per
kWh
[0,1) 0.0 0.0 0.0% 0.0 0.0 -$ [1,2) 30.0 58.2 0.1% 1.0 45.2 6.8$ [2,3) 1.0 2.9 0.0% 0.0 2.3 0.3$ [3,4) 158.0 617.7 1.2% 10.3 480.0 72.0$ [4,5) 10482.0 46782.8 88.8% 779.7 36350.7 5,452.6$ [5,6) 213.0 1138.3 2.2% 19.0 884.4 132.7$ [6,7) 140.0 919.0 1.7% 15.3 714.1 107.1$ [7,8) 110.0 814.6 1.5% 13.6 633.0 94.9$ [8,9) 32.0 269.6 0.5% 4.5 209.4 31.4$ [9,10) 20.0 189.7 0.4% 3.2 147.4 22.1$ [10,20) 43.0 582.6 1.1% 9.7 452.7 67.9$ [20,30) 26.0 636.7 1.2% 10.6 494.7 74.2$ [30,40) 17.0 598.7 1.1% 10.0 465.2 69.8$ [40,50) 2.0 81.1 0.2% 1.4 63.0 9.5$ [50,9999) 0.0 0.0 0.0% 0.0 0.0 -$ Grand Total 11274.0 52691.9 100% 878.2 40942.1 6,141.3$
Summary of power consumption (kW) at one minute interval over the entire monitoring period
112
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
[0,1)
[1,2)
[2,3)
[3,4)
[4,5)
[5,6)
[6,7)
[7,8)
[8,9)
[9,10)
[10,20)
[20,30)
[30,40)
[40,50)
[50,9999)
Energyconsumptionpercentage
Powerconsumptiongroupsbasedonvalue(kW)
113
Figure9-Timeseriesofthepowerconsumption(kW)foreachsingledayatoneminuteintervalover24-hoursperiod
0
5
10
15
20
25
30
35
40
45:00
:26
:52
:18
:44
:10
:36
:02
:28
:54
:20
:46
:12
:38
:04
:30
:56
:22
:48
:14
:40
:06
:32
:58
:24
:50
:16
:42
:08
:34
:00
:26
:52
:18
:44
:10
:36
:02
:28
:54
:20
:46
:12
:38
:04
:30
:56
:22
:48
:14
:40
:06
:32
:58
:24
:50
12
AM
1AM 2AM 3AM 4AM 5AM 6AM 7AM 8AM 9AM 10
AM
11
AM
12PM 1PM 2PM 3PM 4PM 5PM 6PM 7PM 8PM 9PM 10PM11PM
Powerconsumption(kW)
1/1/2010 1/2/2010 1/3/2010 1/4/2010 1/5/2010 1/6/2010 1/7/2010 1/8/2010 1/9/2010
114
Figure10-Timeseriesofthepowerconsumption(kW)foreachminuteaveragedovertheeightdays
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0:00
:27
:54
:21
:48
:15
:42
:09
:36
:03
:30
:57
:24
:51
:18
:45
:12
:39
:06
:33
:00
:27
:54
:21
:48
:15
:42
:09
:36
:03
:30
:57
:24
:51
:18
:45
:12
:39
:06
:33
:00
:27
:54
:21
:48
:15
:42
:09
:36
:03
:30
:57
:24
:51
12
AM
1AM 2AM 3AM 4AM 5AM 6AM 7AM 8AM 9AM 10
AM
11
AM
12
PM
1PM 2PM 3PM 4PM 5PM 6PM 7PM 8PM 9PM 10
PM
11
PM
Powerconsumption(kW)
115
Figure11-Frequencycountofthepowerconsumption(kW)atoneminuteintervalover8days
kW Range (kW) Counts 0-2 30 2-4 159 4-6 10695 6-8 250 8-10 52 10-12 22 12-14 6 14-16 2 16-18 4 18-20 9 20-22 5 22-24 6 24-26 8 26-28 5 28-30 2 30-32 2 32-34 3 34-36 3 36-38 9 40-42 2 Grand Total 11274
0
2000
4000
6000
8000
10000
12000
0-2
2-4
4-6
6-8
8-10
10-12
12-14
14-16
16-18
18-20
20-22
22-24
24-26
26-28
28-30
30-32
32-34
34-36
36-38
40-42
Count
Total
116
Figure12-Powerconsumptionamount(kW)ofeachrange
Forexample,thesumofminutelykWvaluesthatfallinto4-6is47921.1 over the 8 monitoring days.
kWT Range (kW) Sum of kWT_kw
0-2 58.2 2-4 620.6 4-6 47921.1 6-8 1733.6 8-10 459.2 10-12 238.1 12-14 77.4 14-16 30.4 16-18 66.9 18-20 169.8 20-22 107.0 22-24 136.9 24-26 201.4 26-28 132.9 28-30 58.5 30-32 61.2 32-34 97.4 34-36 104.8 36-38 335.3 40-42 81.1 Grand Total 52691.9
0.0
10000.0
20000.0
30000.0
40000.0
50000.0
60000.0
0-2
2-4
4-6
6-8
8-10
10-12
12-14
14-16
16-18
18-20
20-22
22-24
24-26
26-28
28-30
30-32
32-34
34-36
36-38
40-42
Amountofpowerconsumptionover8days
117
Figure13-Powerconsumptionpercentageofeachrange
Forexample,powerconsumptionbythekWrangethatfallsinto4-6kWrange,represents90.9%ofthetotalpower
consumptionbyallgroups.
kW Range (kW) Percentage 0-2 0.1% 2-4 1.2% 4-6 90.9% 6-8 3.3% 8-10 0.9% 10-12 0.5% 12-14 0.1% 14-16 0.1% 16-18 0.1% 18-20 0.3% 20-22 0.2% 22-24 0.3% 24-26 0.4% 26-28 0.3% 28-30 0.1% 30-32 0.1% 32-34 0.2% 34-36 0.2% 36-38 0.6% 40-42 0.2% Grand Total 100.0%
0.0%
10.0%
20.0%
30.0%
40.0%
50.0%
60.0%
70.0%
80.0%
90.0%
100.0%
0-2
2-4
4-6
6-8
8-10
10-12
12-14
14-16
16-18
18-20
20-22
22-24
24-26
26-28
28-30
30-32
32-34
34-36
36-38
40-42
Percentageofthetotalenergyconsumptionover8
days
118
Figure14-Powerconsumptionpercentageofeachtheoreticalscanningmode
kWT Range (kW)
Sum of kWT_kw
Percentage of each range
0-2 58.2 0.11% 2-4 620.6 1.18% 4-6 47921.1 90.95% 6+ 4092.0 7.77% Grand Total 52691.9 100.00%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0-2 2-4 4-6 6+
Percentageofeachrange
119
Figure15-Timeseriesofthepowerconsumption(kW)foreachminuteovereachhour
120
121
122
123
124
125
126
127
128
129
130
131
132
Appendix 3.2.4 CT Energy Consumption Data Site #3 Figure1:CT:Toshiba(AquilionOneTSX-305A,2013).Test#1-Site#3
˜
133
Appendix 3.3: X-Ray Data
Appendix 3.3.1: X-Ray Data Site #1a TOSHIBA-KXO-80XMX-RayGeneratorwithMDX-8000TableakaUltimaxSystem(Room1166)Table1:X-raySite1:Powerconsumption(kW)over6-daysofmonitoring.
Summary of power consumption* (kW) at six minutes interval over the monitoring period for BC XRay in Room #1166
* Average kW reading was used for this analysis.
kW Range (kW)
Count of kW
Frequency Percentage
Average of kW (kW)
Energy consumption of each kW range
over sampling period (kWmin)
Energy consumption of each kW range
over sampling period (kWh)
Energy consumption
Percentage of each kW range
Estimated Energy Consumption over One Year
(kWh)
Estimated annual cost
@$0.15 per kWh
[0, 0.1) 0 0.0% NA 0.0 0.0 0.0% 0.0 -$ [0.1, 0.2) 959 80.7% 0.18 1022.3 17.0 44.7% 1255.3 188.3$ [0.2, 0.3) 0 0.0% NA 0.0 0.0 0.0% 0.0 -$ [0.3, 0.4) 2 0.2% 0.33 4.0 0.1 0.2% 4.9 0.7$ [0.4, 0.5) 1 0.1% 0.50 3.0 0.0 0.1% 3.7 0.6$ [0.5, 0.6) 1 0.1% 0.51 3.1 0.1 0.1% 3.8 0.6$ [0.6, 0.7) 1 0.1% 0.66 4.0 0.1 0.2% 4.9 0.7$ [0.7, 0.8) 6 0.5% 0.76 27.5 0.5 1.2% 33.8 5.1$ [0.8, 0.9) 13 1.1% 0.85 66.6 1.1 2.9% 81.8 12.3$ [0.9, 1) 199 16.7% 0.93 1116.4 18.6 48.8% 1370.8 205.6$ [1, 1.1) 7 0.6% 1.01 42.6 0.7 1.9% 52.3 7.8$ [1.1, 99) 0 0.0% NA 0.0 0.0 0.0% 0.0 -$ Grand Total 1189 1.0 0.32 2289.4 38.2 100% 2811.3 421.7$
134
Figure1–EnergyConsumptionPercentageofeachpowerrangeForexample,theenergyconsumptionbypowerrangethatfallinto2-3kWcontributedto73.3%ofthetotalenergyconsumption over the monitoring period.
0%
10%
20%
30%
40%
50%
60%
[0,0.1) [0.1,0.2) [0.2,0.3) [0.3,0.4) [0.4,0.5) [0.5,0.6) [0.6,0.7) [0.7,0.8) [0.8,0.9) [0.9,1) [1,1.1) [1.1,99)
Power(kW)
EnergyconsumptionPercentageofeachkWrange
135
Figure2–Timeseriesofpowerconsumptionforeachday
136
137
138
139
140
141
Appendix 3.3.2 X-Ray Site 1b Room1168–ToshibaKX0-80SX-RayGeneratorTable1:X-RaySite1.-Powerconsumption(kW)over3-daysofmonitoring.
Summary of power consumption* (kW) at six minutes interval over the monitoring period for BC Xray #2 in Room #1168
* Average kW reading was used for this analysis.
kW Range (kW)
Count of kW
Frequency Percentage
Average of kW (kW)
Energy consumption of each kW range
over sampling period (kWmin)
Energy consumption of each kW range
over sampling period (kWh)
Energy consumption
Percentage of each kW range
Estimated Energy Consumption over One Year
(kWh)
Estimated annual cost
@$0.15 per kWh
[0, 0.06) 0 0.0% NA 0.0 0.0 0.0% 0.0 -$ [0.06, 0.07) 1 0.2% 0.07 0.4 0.0 0.2% 1.4 0.2$ [0.07, 0.08) 279 63.0% 0.08 129.0 2.2 61.7% 425.2 63.8$ [0.08, 0.09) 163 36.8% 0.08 79.6 1.3 38.1% 262.4 39.4$ [0.09, 99) 0 0.0% NA 0.0 0.0 0.0% 0.0 -$ Grand Total 443 1.0 0.08 209.1 3.5 100% 689.0 103.3$
142
Figure1–EnergyConsumptionPercentageofeachpowerrange
Forexample,theenergyconsumptionbypowerrangethatfallinto0.07-0.08kWcontributedto61.7%ofthetotalenergyconsumption over the monitoring period.
0%
10%
20%
30%
40%
50%
60%
70%
[0,0.06) [0.06,0.07) [0.07,0.08) [0.08,0.09) [0.09,99)
Power(kW)
EnergyconsumptionPercentageofeachkWrange
143
Figure2–Timeseriesofpowerconsumptionforeachday
144
145
146
147