Caterpillar Engine TechnologiesAn Engine System Approach toExhaust Waste Heat RecoveryPrincipal Investigator: Richard W. KruiswykCaterpillar Inc.Note: This presentation does not contain any proprietary or confidential information.DOE Contract: DE-FC26-05NT42423DOE Technology Manager: John FairbanksNETL Project Manager: Carl MarondeDEER ConferenceDetroit, MIAugust 6, 2008Caterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialAGENDAOverview - Engine Thermal Efficiency and Waste Heat RecoveryEWHR Program Objectives, Timeline, ScopeTechnical DevelopmentsSummary and ConclusionsCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialDiesel Engine Thermal EfficiencyCGI HeatRejectionFuelEnergyEngineHeatRejectionExhaustEnergyATAAC HeatRejectionBrakePowerAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFCGICoolerCGIBrakePowerAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFCGICoolerCGIBrakePowerFuel•Series Turbocharged•LPL CGI (clean gas induction)2007 C15 On-Highway Truck020406080100

Fuel Energy (kW)Fuel Energy, %~ 10%~ 22%Brake PowerCoolantHeat RejCGI Cooler HRATAAC HRExhaustEnergy~ 42%~ 21%~ 5%Caterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialDiesel Engine Thermal Efficiency & Exhaust Waste HeatLPL Engine020406080100

Fuel Energy (kW)Fuel Energy, %~ 8%~ 22%Brake PowerCoolantHeat RejEGR Cooler HRATAAC HRExhaustEnergy~ 42%~ 21%~ 7%HPL EngineAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFBrakePowerEGRHEAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFBrakePowerEGRHEAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFCGICoolerCGIBrakePowerAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFCGICoolerCGIBrakePower020406080100

Fuel Energy (kW)Fuel Energy, %~ 10%~ 22%Brake PowerCoolantHeat RejCGI Cooler HRATAAC HRExhaustEnergy~ 42%~ 21%~ 5%Roughly half of the lost fuel energy iscarried in the exhaust streamsCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-Confidential020406080100

Fuel Energy, % )Diesel Engine Thermal Efficiency & Exhaust Waste HeatHTCD 50% OTE Program –Analysis Results15%15%25%45.0%OTEResearch45% OTEEngineHE NoxA/TImprovedAir SystemReducedHeatRejectionTurbocompoundCombustionSystemOptimizationBrakePowerCoolantHeat RejATAAC HRExhaustEnergyATAIC HREGR HR45.2%OTE47.0%OTE47.3%OTE48.2%OTE50.5%OTE26%9%14%Waste heat recovery from the exhauststreams will be essential to achieving50 -55% thermal efficiencyCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialChallenges to Efficient Exhaust Waste Heat RecoveryTurbocompoundTechnologyChallenges for2010 & BeyondBottomingCyclesTurbo EfficienciesTransmissionAftertreatment BPCycle EfficienciesPackagingTransmissionAftertreatmentinlet temperaturesDevelopment NeedsTurbo EfficienciesElectrical MachinesCombustionAftertreatmentCompact HeatExchangersCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialAGENDAOverview - Engine Thermal Efficiency and Waste Heat RecoveryEWHR Program Objectives, Timeline, ScopeTechnical DevelopmentsSummary and ConclusionsCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialProgram ObjectiveDevelop components, technologies,and methods torecover energylost in theexhaust processesof an internal combustion engine andutilize that energyto improve engine thermal efficiency by 10% (i.e.from ~ 42% to ~46% thermal efficiency)No increase in emissionsNo reduction in power densityCompatible with anticipated aftertreatmentCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialPhase 220062005DefineRoadmap200720082009Phase 1Validateroadmap20102011Phase 3Phase 4Refine RecipeFinal System DemoPhase 5Mid-ProgramSystem DemoWe are herePhase 3 Objective: Demonstration of significant progress (+ 5-10%) in system thermalefficiency improvement via testing/analysisof prototype components. This will includean on-engine system demonstration of prototype hardware.Program Phases Per ContractProgram TimelineCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialProgram scope revised to includeinvestigation of LPL & HPLsolutionsLPL CGI SystemAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFCGICoolerCGIBrakePowerAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFCGICoolerCGIBrakePowerSolutions compatible w/ production engines –transferable technologies–Baseline -2007 C15 on-highway engine withLPL CGI systemHECC HPL EGR SystemAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFBrakePowerEGRHEAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFBrakePowerEGRHESolutions compatible with future engines –technologies for HECC solutions–HPL or HPL-LPL advantageous in somescenariosProgram ScopeCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialAGENDAOverview - Engine Thermal Efficiency and Waste Heat RecoveryEWHR Program Objectives, Timeline, ScopeTechnical DevelopmentsSummary and ConclusionsCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialTechnical Developments–Proposed SystemAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFCGICoolerCGIBrakePowerAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFCGICoolerCGIBrakePowerPort Insul.(0.5%)Piping(0.5%)Intercooling(1.3%)I/CHP Turbine(2.0%)LP Turbine(1.0%)Compressors(0.7%)* Turbocompound or bottoming cycle: supplementsengine power via electrical or mechanical connectionto flywheelStack Recovery*(4.0%)An integrated system solution towaste heat recoveryStrategy Optimization

Energy transmissionCaterpillar Engine TechnologiesCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialEarly in program:•2010 A/T backpressure levels notknown with certainty•Turbocompound known to benegatively affected by backpressureForced consideration of“backpressure insensitive”solutionsAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFCGIBrakePowerHETurbCompAmbientStackAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFCGIBrakePowerHETurbCompAmbientStackPhase 1 Proposed SolutionOpen Air BraytonCyclePerformance Objective CAN bemet with BraytonCycle Solutionand supporting technologiesPackaging???Technical Developments –Stack Energy Recovery2.8%3.5%4.3%4.0%3.0%2.3%050010001500200025003000500 1000 1500 2000

Engine LoadEngine Speed2.8%3.5%4.3%4.0%3.0%2.3%050010001500200025003000500 1000 1500 2000

Engine LoadEngine SpeedPhase 2 Engine SimulationsBSFC Benefit of Braytonon C15Braytoncycle w/ high efficiencyturbomachinery & insulated exhaust portsCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-Confidential3⁄4Microchannel manufacturing technologyConcept design: 1.5 ft3core vol.Preliminary estimate: ~ 0.5 -1 ft3core2 ft3core vol.Caterpillar technology3⁄4Primary Surface technologyPhase 2Heat Exchanger Technology EvaluationsAt end of Phase 2, no line ofsight to a HE core smaller than1.5 –2.0 ft3AmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFCGIBrakePowerHETurbCompAmbientStackAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFCGIBrakePowerHETurbCompAmbientStackPhase 1 Proposed SolutionOpen Air BraytonCyclePackaging???Technical Developments –Stack Energy RecoveryCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFCGIBrakePowerHETurbCompAmbientStackAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFCGIBrakePowerHETurbCompAmbientStackPackaging???Phase 2 Packaging Studies with1 ft3heat exchanger coreEven at 1 ft3core volume,system packaging is challengeTechnical Developments –Stack Energy RecoveryPhase 1 Proposed SolutionOpen Air BraytonCycleCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialTechnical Developments –Stack Energy RecoveryElectric TurbocompoundGen1 – Caterpillar / DOE2001-2004 Development Program–Approach –Turbocompound function integrated into engine turbo–Specification –40kw @ 60krpm in generating modeMeasured Turbo Shaft Generator Power and Torque0500010000150002000025000300003500040000450005000025000 30000 35000 40000 45000 50000 55000 60000 65000Turbo Shaft Speed rpm

Generator Pow er W0102030405060708090100Elecronics O/ P pow er (W)% Torque–Results•Excellent stability of rotor / shaft system•Generated 44kw at 59krpm–Turbo generator short of efficiency target–Heating problems –powers above 15kw limited to 30-60sec runtimeCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialTechnical Developments –Stack Energy RecoveryGen2 – Concept design collaboration with consultant–Specification: 20-25kw power generation–Two design options to be evaluated•‘Between-the-wheels’option•‘In-front-of-compressor’option–Thermal, stress, rotordynamicanalysis to evaluate options–Scheduled completion: 30Oct08FlywheelMotor/GeneratorHEAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFEGRBrakePowerI/C Electrical PowerGEN.FlywheelMotor/GeneratorHEAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFEGRBrakePowerI/C Electrical PowerGEN.HEAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFEGRBrakePowerI/C Electrical PowerFlywheelMotor/GeneratorGEN.HEAmbientStackEngine C15A/CLP CompHP CompLP TurbHP TurbDPFEGRBrakePowerI/C Electrical PowerFlywheelMotor/GeneratorGEN.Electric TurbocompoundCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialTechnical Developments –HP TurbinePort Insul.(0.5%)Piping(0.5%)Intercooling(1.3%)HP Turbine(2.0%)LP Turbine(1.0%)Compressors(0.7%)Stack Recovery(4.0%)Strategy Optimization+2% Thermal Efficiency Requires+10% Turbine Stage Efficiency0.6800.7000.7200.7400.7600.7800.8000.8200.8400.550.60.650.70.750.8Velocity Ratio, U/CBaseline2%Target +10%

Turbine-Mech Efficiency, T-S0.6800.7000.7200.7400.7600.7800.8000.8200.8400.550.60.650.70.750.8Velocity Ratio, U/CBaseline2%Target +10%

Turbine-Mech Efficiency, T-STechnologiesRND – radial, nozzled, divided turbineMixed Flow TurbineCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialNozzled / Divided Turbine vs Production0.6800.7000.7200.7400.7600.7800.8000.8200.8400.550.60.650.70.750.8Velocity Ratio, U/C

Turbine-Mech Efficiency, T-SBaselineRND MeasuredTarget2%Nozzled / Divided Turbine vs Production

Turbine-Mech Efficiency, T-SRND OptimizedNozzled / Divided Turbine vs Production0.6800.7000.7200.7400.7600.7800.8000.8200.8400.550.60.650.70.750.8Velocity Ratio, U/C

Turbine-Mech Efficiency, T-SBaselineRND MeasuredTarget2%Nozzled / Divided Turbine vs Production

Turbine-Mech Efficiency, T-SRND OptimizedTechnical Developments –HP TurbinePort Insul.(0.5%)Piping(0.5%)Intercooling(1.3%)HP Turbine(2.0%)LP Turbine(1.0%)Compressors(0.7%)Stack Recovery(4.0%)Strategy OptimizationMajority of exhaust energy isentering turbine inthis regionShift efficiencypeakGapCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialNozzled / Divided Turbine vs Production0.6800.7000.7200.7400.7600.7800.8000.8200.8400.550.60.650.70.750.8Velocity Ratio, U/C

Turbine-Mech Efficiency, T-SBaselineRND MeasuredTarget2%Nozzled / Divided Turbine vs Production

Turbine-Mech Efficiency, T-SRND OptimizedNozzled / Divided Turbine vs Production0.6800.7000.7200.7400.7600.7800.8000.8200.8400.550.60.650.70.750.8Velocity Ratio, U/C

Turbine-Mech Efficiency, T-SBaselineRND MeasuredTarget2%Nozzled / Divided Turbine vs Production

Turbine-Mech Efficiency, T-SRND OptimizedTechnical Developments –HP TurbinePort Insul.(0.5%)Piping(0.5%)Intercooling(1.3%)HP Turbine(2.0%)LP Turbine(1.0%)Compressors(0.7%)Stack Recovery(4.0%)Strategy OptimizationNew TargetShifting peak efficiency –mixed flow turbineCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialTechnical Developments –HP TurbineMixed Flow Turbineradial mixed flowGen1 wheel designed / procured / testedGen1 missed target performance:Over-aggressive design–Desire to clearly demoefficiency shiftFirst use of codes for mixed flow–Calibration requiredMF Turbine vs 2007 Production HP0.620.640.660.680.70.720.740.760.5 0.55 0.6 0.65 0.7 0.75 0.8Velocity Ratio, U/C

Turb-Mech Eff, T-S (%)Production Radial – DataMixed Flow – Gen1 DataTarget – Nozzleless Mixed Flow

Turbine-Mech Eff. T-SMF Turbine vs 2007 Production HP0.620.640.660.680.70.720.740.760.5 0.55 0.6 0.65 0.7 0.75 0.8Velocity Ratio, U/C

Turb-Mech Eff, T-S (%)Production Radial – DataMixed Flow – Gen1 DataTarget – Nozzleless Mixed Flow

Turbine-Mech Eff. T-SCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialTechnical Developments –HP TurbineGen2 wheel designed / analyzed–Gen1 lessons used to optimize designMixed Flow TurbineGen2Gen1MF Turbine vs 2007 Production HP0.620.640.660.680.70.720.740.760.5 0.55 0.6 0.65 0.7 0.75 0.8Velocity Ratio, U/C

Turb-Mech Eff, T-S (%)Production Radial DataMixed Flow – Gen1 DataGen2 Mixed Flow - Predicted

Turbine-Mech Eff. T-SMF Turbine vs 2007 Production HP0.620.640.660.680.70.720.740.760.5 0.55 0.6 0.65 0.7 0.75 0.8Velocity Ratio, U/C

Turb-Mech Eff, T-S (%)Production Radial DataMixed Flow – Gen1 DataGen2 Mixed Flow - Predicted

Turbine-Mech Eff. T-S–6-8% improvement in efficiency predicted vsGen1 over range of interestCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialBraytonCycleSystem Capability EvaluationHEAmbientStackEngine C15A/CCompTurbDPFEGRBrakePowerTurbComp Electrical PowerFlywheelMotor/GeneratorGEN.Brayton CycleAmbientAmbientHEAmbientStackEngine C15A/CCompTurbDPFEGRBrakePowerTurbComp Electrical PowerFlywheelMotor/GeneratorGEN.Brayton CycleAmbientAmbientAssumptions:–Braytonturbo efficiencies 80%–Single stage for packaging–Heat exchanger: 90% effectiveness–Transmission Efficiency: 90%1.01.52.02.53.03.54.04.520.025.030.035.040.045.0EGR Flow Rate (%)

BSFC Improvement (%)Packaging: Excellent–Heat Exchanger:0.25 ft3core–Turbo:~ 2”compressorPerformance: Low-Moderate–At 20 -40% EGR:+ ~2 -4% w/ 80% turbomachinery+ ~1.5 -2.5% w/ 74% turbomachineryTechnical Developments –HECCHPL EGR WasteHeat RecoveryCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialRankineCycleSystem Capability EvaluationSHAmbientStackEngine C15A/CCompTurbDPFEGRBrakePowerTurbPump Electrical PowerFlywheelMotor/GeneratorGEN.Rankine CycleEVCondRCSHAmbientStackEngine C15A/CCompTurbDPFEGRBrakePowerTurbPump Electrical PowerFlywheelMotor/GeneratorGEN.Rankine CycleEVCondRC22.533.544.555.566.57202530354045% EGR

BSFC Improvement (%)Packaging: Challenge–Multiple heat exchangersPerformance: Moderate-Good–+ 3-6% depending on EGR rates660degC680degCExhaust temp640degCAssumptions:–Turbine efficiency 80%–Pump efficiency 65%–R245fa working fluid–Transmission Efficiency: 90%Technical Developments –HECCHPL EGR WasteHeat RecoveryCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialAGENDAOverview - Engine Thermal Efficiency and Waste Heat RecoveryEWHR Program Objectives, Timeline, ScopeTechnical DevelopmentsSummary and ConclusionsCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialSummarySignificant progress made toward program objectives:With LPL CGI, turbocompound + high efficiency turbos provides+4% BSFC w/ 20kPa aftertreatment backpressure.Progress on supporting technologies, especially turbinetechnologies, suggests performance target can be metWaste heat recovery for future HECC engine solutions promptsconsideration of HPL and HPL-LPL EGR configurations–Turbocompound still effective for stack recovery. Benefitdependent on aftertreatment backpressure, required EGR rates–Braytoncycle offers moderate benefit for HPL loop heat recovery–Rankinecycle offers significant benefit for HPL loop heat recoveryCaterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialAcknowledgementsTurbomachinery design consulting,component procurement and integration.Turbomachinery design consulting andoptimization.Turbomachinery design consulting andoptimization.Caterpillar Thanks:Electric turbocompound designconsultingHoneywellConceptsNRECTurbo SolutionsBarber-Nichols Inc.Caterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-ConfidentialAcknowledgements•Department of Energy•GurpreetSingh•John Fairbanks•DOE National Energy Technology Laboratory•Ralph Nine•Carl MarondeCaterpillar Thanks:Caterpillar Confidential: XXXXXEngine TechnologiesCaterpillar Non-Confidential