Exhaust EnergyRecoveryAugust 5th, 2009Chris NelsonResearch & TechnologyDoE Contract DE-FC26-05NT42419Exhaust Energy Recovery Program GoalsExhaust Energy Recovery proposed to achieve:10% Fuel Efficiency ImprovementReduce or eliminate the need for increased heat rejectioncapacity for future heavy duty engines in Class 8 TractorsA 10% increase in fuel efficiency would:Save a linehaul, Class 8 truck over 1800 gallons of fuel per yearReduce exhaust emissions due to less fuel useReducing the need for increased heat rejection:Helps maintain the aerodynamicadvantages of today’s trucks2Innovation You Can Depend On3Innovation You Can Depend OnExhaust Energy Recovery ConceptOrganic Rankine Cycle------------------------------------------Converts otherwise wastedthermal energy from the EGRand main exhaust gasstreamsWorks best for high-EGR flowengine recipes for low-NOxcombustionCompTurb



# Exh.ManifoldExhaustAir In

Intake ManifoldTurbine

GeneratorRam Airflow



# ISX EnginePower Out CondenserEGRValveCACWHRCondenser CoolerEngineRadiatorMechanical FanAftertreatmentBoilerFMGExh. Boiler RecupeSuperheaterPowerConditioning4Innovation You Can Depend On012345678910 C 1 0 0 B 1 0 0 B 7 5 B 6 3 B 5 0 B 2 5 A 1 0 0 H D C C ( a l l )

H D C C ( F l a t )2010 EGR Original2010 EGR Original+ExhAssumptions:Condenser Size = 0.65 m^2T_amb = 55 F7.4% BTE BenefitProgram AccomplishmentsFuel Efficiency Improvement Results

BTE Improvement5Innovation You Can Depend OnRecipe for 10% Efficiency Improvement6%fromEGR energy+ 2%fromExhaust+ 2%fromElectric Acc.10%ImprovementOur hardware results showedthat our predictions were validand realisticCompTurb



# Exh.ManifoldExhaustAir In

Intake ManifoldTurbine

GeneratorRam Airflow



# ISX EnginePower Out CondenserEGRValveCACWHRCondenser CoolerEngineRadiatorMechanical FanAftertreatmentBoilerFMGExh. Boiler RecupeSuperheaterPowerConditioningOriginal System ArchitecturePlans and AssumptionsA low engine-out NOx combustion recipe was a keyingredient of the original proposalEngine architecture used forfirst-generation EER system designtargeted 0.2 gm BSNOX engine-out emissionsEGR Charge Mass flow provided a high level of recoverable EGRenergy – 6% recovered from EGR along with first prototypehardwareAdditional energy was recovered from the engine’s main exhaustgas stream to keep the system at its full potential – we hit ourpredicted 2% additional benefit targetSystem performance was limited tothe heat rejection capacity of aMY2007 Class 8 tractor6Innovation You Can Depend OnEngine Architecture ChangesAffect of SCR AftertreatmentCummins announced during August of 2008 that it would useSCR-based aftertreatment on its 2010 heavy-duty enginesOur recipe to maximize the recovery of EGR and ExhaustGas heat within the limit of the vehicle’s cooling modulecapacity was therefore tuned for performance with lowerEGR flow:7Innovation You Can Depend On8Innovation You Can Depend OnTest Results from ISX’07012345678910 C 1 0 0 B 1 0 0 B 7 5 B 6 3 B 5 0 B 2 5 A 1 0 0 H D C C ( a l l )

H D C C ( F l a t )2007 EGR2007 EGR+ExhAssumptions:Condenser Size = 0.65 m^2T_amb = 55 F6.2% BTE Benefit

BTE ImprovementEngine Architecture ChangesOptimization of SCR aftertreatment will further erodethe benefit of EGR-based energy recoveryEngine-out NOx levels will rise with SCR conversion efficiencyimprovement, however a significant level of EGR will remainWe have demonstrated how we can tune an engine-integrated ORCsystem to recover energy and provide a benefit within the confinesof the existing heat rejection space on-vehicleWe therefore investigated to determine the realisticpotential of ORC energy recovery –9Innovation You Can Depend On10Innovation You Can Depend OnORC Energy Recovery PotentialWHRCoolant HeatRecoveryVehicle/CondenserCapacityComponentEfficienciesWorkingFluidEGR HeatRecoveryExhaust HeatRecoveryCharge Air HeatRecoveryORC Energy Recovery PotentialWHRCoolant HeatRecoveryCharge Air HeatRecoveryExhaust HeatRecoveryEGR HeatRecoveryVehicle/CondenserComponentEfficienciesWorkingFluidCapacityFrom bulk coolant at 200FPotential for + ~0.5% improvementUtilize existing engine design/hardware, AEG, water pump,Recovery from AEG to working fluid heat exchangerEliminate radiator, system cooling with WHR condenser onlyVery low potential benefit for extra system cost/complexityThe potential recovery benefit from bulk coolant flow represents only what may beaccomplished with existing architecture(AEG or non-boiling,water-based cooling).Data updated from SMMR material11Innovation You Can Depend OnORC Energy Recovery PotentialWHRCoolant HeatCharge Air HeatExhaust HeatEGR HeatVehicle/ComponentWorkingRecoveryRecoveryRecoveryRecoveryCondenserEfficienciesFluid+0.5%CapacityCharge Air Heat Recovery would add +~1.0%Recovery from Charge Air Pre-CoolerRequires smaller Air-Air Finishcooler to meet IMT requirementsData updated from SMMR material12Innovation You Can Depend OnORC Energy Recovery PotentialWHRCoolant HeatCharge Air HeatExhaust HeatEGR HeatVehicle/ComponentWorkingRecovery+0.5%Recovery+1.0%RecoveryRecoveryCondenserCapacityEfficienciesFluidExhaust recovery performed to maximize use ofheat rejection capacityAmount of benefit depends on EGRrecipe and cooling system capacity~3.5% BTE benefit shown at ’07 EGR recipeData updated from SMMR material13Innovation You Can Depend OnORC Energy Recovery PotentialWHRCoolant HeatCharge Air HeatExhaust HeatEGR HeatVehicle/ComponentWorkingRecoveryRecovery RecoveryRecoveryCondenserEfficienciesFluid+0.5%+1.0%+3.0%Capacity2.5% BTE benefit shown at ’07 EGR recipeBenefit is dependent on EGR recipeThis will likely be ~2% withlower EGR-recipe enginesData updated from SMMR material14Innovation You Can Depend OnORC Energy Recovery PotentialWHRCoolant HeatCharge Air HeatExhaust HeatEGR HeatVehicle/ComponentWorkingRecoveryRecoveryRecoveryRecoveryCondenserEfficienciesFluid+0.5%+1.0%+3.0%+2.0%CapacityDoubling ’07-based condensersize adds ~2% benefitAssume 1% benefit is realistically achievableDependent on OEM CapabilityData updated from SMMR material15Innovation You Can Depend OnORC Energy Recovery PotentialWHRCoolant HeatCharge Air HeatExhaust HeatEGR HeatVehicle/ComponentWorkingRecoveryRecovery Recovery RecoveryCondenserEfficienciesFluid+0.5%+1.0%+3.0%+2.0%Capacity +1%Turbine Efficiency at ~75% in 1stGenTurbine efficiency could be higher1stGen Power Transfer Efficiency @90% could be greaterPump Efficiencies1stGen Pump Efficiencies were ~30%Flow LossesValve lossesFlow losses in heat exchangersPiping/Plumbing Flow LossesData updated from SMMR material16Innovation You Can Depend OnORC Energy Recovery PotentialWHRCoolant HeatRecoveryCharge Air HeatRecoveryExhaust HeatRecoveryEGR HeatRecoveryVehicle/CondenserComponentEfficienciesWorkingFluid+0.5%+1.0%+3.0%+2.0Capacity +1%+1%Performance is limited byfluid’s peak temperatureControls Refinement would allow operating much closer to breakdown limitOperating at significantly higher fluid tempmay achieve 1% benefitHigher temperature robustness must be demonstrated long-termData updated from SMMR material17Innovation You Can Depend OnORC Energy Recovery PotentialWHR~9.5%BTE BenefitCoolant HeatCharge Air HeatExhaust HeatEGR HeatVehicle/ComponentWorkingRecoveryRecovery Recovery RecoveryCondenserEfficienciesFluid+0.5%+1.0%+3.0%+2.0%Capacity +1%+1% +1%Nearly a 10% performance improvement is possible – though with highadditional cost and system complexityFuture development must focus on the most promising and realisticpotentials energy recovery sources -Data updated from SMMR material18Innovation You Can Depend OnORC Energy Recoveryfor 2ndGeneration DevelopmentWHRBTE BenefitCoolant HeatCharge Air HeatExhaust HeatEGR HeatVehicle/ComponentWorkingRecoveryRecoveryRecoveryRecoveryCondenserEfficienciesFluid+0.5%+1.0%+3.0%+2.0%Capacity +1%+1%+1%Next generation development will target the highest-return recovery opportunities –EGR, Exhaust and Charge Air – the hottest waste heat streams on the engine•Vehicle Condenser Capacity benefitis dependent on vehicle installation•Component and fluid improvements remain to be demonstratedCost will remain a key focus19Innovation You Can Depend OnReview and SummaryThe Exhaust Energy Recovery program at Cummins hasmade considerable progress –Successfully demonstrated ORC-based energy recovery fromEGR and Exhaust gasSuccessfully delivered our original model-based predictions forsystem performanceIdentified areas for system improvements/optimizationIdentified avenues for development towards the 10% GoalWe continue to work towards a practical implementation of ORC-based WHR to complement future engine development programs20Innovation You Can Depend OnCummins Waste Heat RecoveryCummins Inc. Appreciates the Partnership Support ofthe U.S. Department of Energy in this highlyinnovative and unique program –Thank You!21Innovation You Can Depend On