Exhaust En

Recover

August 5th, 2009 

Chris Nelson 

Research & Techno

DoE Contract DE-FC26-0
Exhaust Energy Recovery Program G

Exhaust Energy Recovery proposed to achieve: 

 10% Fuel Efficiency Improvement  Reduce or eliminate the need for increased heat reje

capacity for future heavy duty engines in Class 8 Tr

A 10% increase in fuel efficiency would: 

 Save a linehaul, Class 8 truck over 1800 gallons of fuel pe Reduce exhaust emissions due to less fuel use 

Reducing the need for increased heat rejection: 

 Helps maintain the aerodynamic advantages of today’s tru

2 Innovation You Can D
3 Innovation You Can D

Exhaust Energy Recovery Conc

Organic Rankine Cycle ------------------------------------------Converts otherwise wasted thermal energy from the EGR and main exhaust gas streams Works best for high-EGR flow engine recipes for low-NOx combustion 

Comp 

Turb 

Exh.Manifold 

Air In 

Intake Manifold 

Ram Airflow 

ISX Engine 

Power Out 

EGR 

Valve 

CAC 

WHR 

Condenser Cooler 

Engine 

Radiator 

Mechanical Fan 

Aftertreatment 

Boiler 

FMG 

Exh. 

Superheater 

Power 

Conditioning 
4 Innovation You Can D

0 1 2 3 4 5 6 7 8 9 

10 

C100 B100 B75 B63 B50 B25 A100 

HDCC (all) 

2010 EGR Original 2010 EGR Original+Exh 

Assu

ConT_am

7.4% BTE 

Program Accomplishments 

Fuel Efficiency Improvement Resul

BTE Improvement 
5 Innovation You Can D

Recipe for 10% Efficiency Improve

6% from EGR energy 

+ 2% from Exhaust + 2% from Electric Acc. 

10% Improvement 

Our hardware results showed that our predictions were validand realistic 

Comp 

Turb 

Exh.Manifold 

Air In 

Intake Manifold 

Ram Airflow 

ISX Engine 

Power Out 

EGR 

Valve 

CAC 

WHR 

Condenser Cooler 

Engine 

Radiator 

Mechanical Fan 

Aftertreatment 

Boiler 

FMG 

Exh. 

Superheater 

Power 

Conditioning 
Original System Architecture

Plans and Assumptions

A low engine-out NOx combustion recipe was a keingredient of the original proposal 

 Engine architecture used for first-generation EER system 

targeted 0.2 gm BSNOX engine-out emissions 

 EGR Charge Mass flow provided a high level of recovera

energy – 6% recovered from EGR along with first prototyhardware 

 Additional energy was recovered from the engine’s main 

gas stream to keep the system at its full potential – we hpredicted 2% additional benefit target 

 System performance was limited to the heat rejection ca

MY2007 Class 8 tractor 

6 Innovation You Can D
Engine Architecture Change

Affect of SCR Aftertreatment 

Cummins announced during August of 2008 that it 

SCR-based aftertreatment on its 2010 heavy-duty 

Our recipe to maximize the recovery of EGR and E

Gas heat within the limit of the vehicle’s cooling mcapacity was therefore tuned for performance witEGR flow:

7 Innovation You Can D
8 Innovation You Can D

Test Results from ISX’07 

0 1 2 3 4 5 6 7 8 9 

10 

C100 B100 B75 B63 B50 B25 A100 

HDCC (a

2007 EGR 2007 EGR+Exh 

AssConT_a

6.2% BTE 

BTE Improvement 
Engine Architecture Change

Optimization of SCR aftertreatment will furthethe benefit of EGR-based energy recovery 

 Engine-out NOx levels will rise with SCR conversion eff

improvement, however a significant level of EGR will re

 We have demonstrated how we can tune an engine-inte

system to recover energy and provide a benefit within t

of the existing heat rejection space on-vehicle 

We therefore investigated to determine the repotential of ORC energy recovery – 

9 Innovation You Can D
10 Innovation You Can D

ORC Energy Recovery Potentia

WHR 

Coolant Heat 

Recovery 

Vehicle/ 

Condenser 

Capacity 

Com

Effic

EGR Heat 

Recovery 

Exhaust Heat 

Recovery 

Charge Air Heat 

Recovery 
ORC Energy Recovery Potentia

WHR

Coolant Heat 

Recovery 

Charge Air Heat 

Recovery 

Exhaust Heat 

Recovery 

EGR Heat 

Recovery 

Vehicle/ 

Condenser 

Com

Effic

Capacity 

From bulk coolant at 200F Potential for + ~0.5% improvement 

Utilize existing engine design/hardware, AEG, water pump, Recovery from AEG to working fluid heat exchanger 

Eliminate radiator, system cooling with WHR condenser only 

Very low potential benefit for extra system cost/complexity 

The potential recovery benefit from bulk coolant flow represents only what may accomplished with existing architecture (AEG or non-boiling, water-based cool

Data updated fro

11 Innovation You Can D
ORC Energy Recovery Potentia

WHR

Coolant Heat Charge Air Heat Exhaust Heat EGR Heat Vehicle/ Com

Recovery Recovery Recovery Recovery Condenser Effic

+0.5% Capacity 

Charge Air Heat Recovery would add +~1.0% 

Recovery from Charge Air Pre-Cooler 

Requires smaller Air-Air Finish cooler to me

Data updated fro

12 Innovation You Can D
ORC Energy Recovery Potentia

WHR 

Coolant Heat Charge Air Heat Exhaust Heat EGR Heat Vehicle/ Com

Recovery 

+0.5% 

Recovery 

+1.0% 

Recovery Recovery Condenser 

Capacity 

Effic

Exhaust recovery performed to maximize use of heat Amount of benefit depends on EGR recipe and cooling 

~3.5% BTE benefit shown at ’07 EGR recipe 

Data updated fro

13 Innovation You Can D
ORC Energy Recovery Potentia

WHR

Coolant Heat Charge Air Heat Exhaust Heat EGR Heat Vehicle/ Com

Recovery Recovery Recovery Recovery Condenser Effic

+0.5% +1.0% +3.0% Capacity 

2.5% BTE benefit shown at ’07 EGR recipe 

Benefit is dependent on EGR recipe 

This will likely be ~2% with lower EGR-recipe engines 

Data updated fro

14 Innovation You Can D
ORC Energy Recovery Potentia

WHR 

Coolant Heat Charge Air Heat Exhaust Heat EGR Heat Vehicle/ Com

Recovery Recovery Recovery Recovery Condenser Effic

+0.5% +1.0% +3.0% +2.0% Capacity 

Doubling ’07-based condenser size adds ~2% benefit 

Assume 1% benefit is realistically achievable 

Dependent on OEM Capability 

Data updated fro

15 Innovation You Can D
ORC Energy Recovery Potentia

WHR

Coolant Heat Charge Air Heat Exhaust Heat EGR Heat Vehicle/ Com

Recovery Recovery Recovery Recovery Condenser Effic

+0.5% +1.0% +3.0% +2.0% Capacity +1% 

Turbine Efficiency at ~75% in 1st Gen 

Turbine efficiency could be higher 

1st Gen Power Transfer Efficiency @90% could be greater 

Pump Efficiencies 

1st Gen Pump Efficiencies were ~30% 

Flow Losses 

Valve losses 

Flow losses in heat exchangers 

Piping/Plumbing Flow Losses 

Data updated fro

16 Innovation You Can D
ORC Energy Recovery Potentia

WHR

Coolant Heat 

Recovery 

Charge Air Heat 

Recovery 

Exhaust Heat 

Recovery 

EGR Heat 

Recovery 

Vehicle/ 

Condenser 

Com

Effic

+0.5% +1.0% +3.0% +2.0 Capacity +1% 

Performance is limited by fluid’s pea

Controls Refinement would allow operating much closer to breakdown limit 

Operating at significantly higher fluid temp may achieve 1% benefit 

Higher temperature robustness must be demonstrated long-term 

Data updated fro

17 Innovation You Can D
ORC Energy Recovery Potentia

WHR

~9.5%

BTE Benefit 

Coolant Heat Charge Air Heat Exhaust Heat EGR Heat Vehicle/ Com

Recovery Recovery Recovery Recovery Condenser Effic

+0.5% +1.0% +3.0% +2.0% Capacity +1% +

Nearly a 10% performance improvement is possible – though wadditional cost and system complexity Future development must focus on the most promising and reapotentials energy recovery sources -

Data updated fro

18 Innovation You Can D
ORC Energy Recovery 

for 2nd Generation Development

WHR 

BTE Benefit 

Coolant Heat Charge Air Heat Exhaust Heat EGR Heat Vehicle/ Com

Recovery Recovery Recovery Recovery Condenser Effic

+0.5% +1.0% +3.0% +2.0% Capacity +1% +

Next generation development will target the highest-return recovery opEGR, Exhaust and Charge Air – the hottest waste heat streams on the • Vehicle Condenser Capacity benefit is dependent on vehicle installat

• Component and fluid improvements remain to be demonstrated 

Cost will remain a key focus 

19 Innovation You Can D
Review and Summary

The Exhaust Energy Recovery program at Cummmade considerable progress – 

Successfully demonstrated ORC-based energy recove

EGR and Exhaust gas 

Successfully delivered our original model-based predi

system performance 

 Identified areas for system improvements/optimization  Identified avenues for development towards the 10% GWe continue to work towards a practical implementati

based WHR to complement future engine developmen

20 Innovation You Can D
Cummins Waste Heat Recove

Cummins Inc. Appreciates the Partnership Suthe U.S. Department of Energy in this highly innovative and unique program – 

Thank You!

21 Innovation You Can D