NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.

Analysis of SMR Thermal 

Augmentation with CHP 

Turbine Exhaust

Michael Penev 

August 21, 2013 

NREL/PR-5400-66836
2

Relevant Characteristics of Typical CHP Turbine

Sources: 

• “Technology Characterization: Gas Turbines”, Energy and Environmental Analysis, Prepared for: Environmental Protection Agency, 2008

• Solar turbines performance specifications: Taurus 60, 5.74 MW turbine

• R. Pravi, G. Moore, “Gas Turbine Emissions and Control”, GE Power Systems, March, 2001, GER-4211

Air intake Exhaust:

• Temperature: 510°C (950°F)

• Mass flow: 171,690 lb/h

• Back-pressure allowance: 

sufficient for steam generator 

heat exchanger (inches water 

column)

• Oxygen content: 15 vol%

Solar Turbines

• Taurus 60

• 5.74 MW
3

Typical SMR System Configuration

Sources: 

• R. Elshout, “Hydrogen Production By Steam Reforming”, Chemical Engineering www.che.com, May 2010 issue, page 34
4

Typical SMR System Configuration

Sources: 

• R. Elshout, “Hydrogen Production By Steam Reforming”, Chemical Engineering www.che.com, May 2010 issue, page 34

Note: Internal pressure is 

sub-atmospheric.
5

Modeling of Typical SMR System

Process conditions source: 

Nexant Inc., “Equipment Design and Cost Estimation for Small Modular Biomass Systems, Synthesis Gas Cleanup, and Oxygen Separation Equipment”, May 2006

20

300

CH4-FEED

20

300

1

510

300

SMR-INTR

-480869.271

STM-HREQ Q

510

0

CHP-HT01

38

1

AIR-2

38

1

OXIDANT

20

0

CH4-BURN

37

-0

RAFF-01

22

-0

BURN-IN

SMR-HEAT -503601.983

22

-0

BURN-IN2

560

-0

EXH2

815

300

REF-01

350

300

REF-02

STM-H02 215935.529

412

300

REF-03

37

-0

REF-07

37

-0

REF-08

37

-0

COND-01

100

-0

REF-06

204

300

REF-04

92163.967

STM-H03

225

300

REF-05

37

H2 -0

100

-0

EXHAUST

STM-H01 204459.200

51185.530

STM-H04 563744.225

STM-HT Q

20

15

H2O-FEED 0.304

PMP-AUXW

20

0

COMB-AIR 5.648

AIR-AUX W

22

-0

3

1528

-0

4

STM-GEN

SELECTOR MANIFOLD

SMR-BRNR

SMR

SGEN02

HTS

FLASH-01

CONDENS SGEN03 LTS

PSA

SGEN01

STM-HT

SGEN04

W-PUMP

AIR-BLWR F-TEMP

FLAMETST Temp eratu re (C)

Pressu re (psig)

Du ty (Watt)

Power(k W )

NREL replicated typical SMR 

model, using ASPEN Plus

Efficiency: 76.3% LHV (without utilities)

Production scale: 1,000 kg/day

Key observations: 

- high quality heat drives gas consumption for process heat

- low quality heat exceeds steam generation demand

- gas consumption reduction can be achieved by high quality heat > 880°C
6

Integration Concept

CHP Exhaust

15%O2

510°C

• SMR combustion air intake is manifolded to accept CHP exhaust

• Fuel is combusted into CHP exhaust to increase heat quality 

• adiabatic flame temperature ~1470°C

• Hand-off pressure = ambient (consistent with SMR construction)
7

7

PraxAir Patent US 7043923 B2, May 16, 2006
8

20

300

CH4-FEED

20

300

1

510

300

SMR-INTR

-480869.271

STM-HREQ Q

510

0

CHP-HT01

38

1

AIR-2

38

1

OXIDANT

20

0

CH4-BURN

37

-0

RAFF-01

22

-0

BURN-IN

SMR-HEAT -503601.983

22

-0

BURN-IN2

560

-0

EXH2

815

300

REF-01

350

300

REF-02

STM-H02 215935.529

412

300

REF-03

37

-0

REF-07

37

-0

REF-08

37

-0

COND-01

100

-0

REF-06

204

300

REF-04

92163.967

STM-H03

225

300

REF-05

37

H2 -0

100

-0

EXHAUST

STM-H01 204459.200

51185.530

STM-H04 563744.225

STM-HT Q

20

15

H2O-FEED 0.304

PMP-AUXW

20

0

COMB-AIR 5.648

AIR-AUX W

22

-0

3

1528

-0

4

STM-GEN

SELECTOR MANIFOLD

SMR-BRNR

SMR

SGEN02

HTS

FLASH-01

CONDENS SGEN03 LTS

PSA

SGEN01

STM-HT

SGEN04

W-PUMP

AIR-BLWR F-TEMP

FLAMETST Temp eratu re (C)

Pressu re (psig)

Du ty (Watt)

Power(k W ) Combustion oxidant 

can be either fresh air 

or CHP exhaust

SMR Model in ASPEN Plus

Operating conditions examined: 

• Reactor outlet temperature 815°C, 880°C

• PSA hydrogen recovery extent: 90%, 97%

Performance metrics:

• Natural gas consumption (process & combustor)

• Low quality heat impact

• Hydrogen production impact
9

9

SMR Configuration Units Baseline CHP+SMR

Config. A

CHP+SMR

Config. B

CHP+SMR

Config. C

CHP+SMR

Config. D

SMR-out temperature °C 815 815 880 815 880

PSA H2 recovery % mol/mol 90% 90% 90% 97% 97%

High quality heat requirement kW-thermal 563,744 616,786 673,342 585,414 678,731

Steam generation heat required kW-thermal 480,869 480,869 480,869 480,869 480,869

Low quality heat available (steam generation) kW-thermal 503,602 503,602 606,113 503,602 606,113

Methane used in production stream mmBTU HHV/kgH2 0.156 0.156 0.133 0.144 0.123

Rafinate used in combustion stream mmBTU HHV/kgH2 0.054 0.054 0.032 0.041 0.020

Fresh methane used in combustion stream mmBTU HHV/kgH2 0.010 0.001 0.022 0.008 0.030

Total methane use mmBTU HHV/kgH2 0.165 0.156 0.155 0.152 0.153

Feedstock use efficiency

(excluding CHP heat & electricity) HHV 81.3% 86.0% 86.8% 88.4% 87.9%

Feedstock use efficiency

(excluding CHP heat & electricity) LHV 76.3% 80.7% 81.5% 83.0% 82.5%

Total CH4 consumption reduction 0.0% 5.5% 6.3% 8.1% 7.5%

Performance Summary

Initial indication shows as much as 8% fuel consumption reduction.

Integration ratio: 1 MW CHP can augment 14,000 kg/day SMR 
10

10

Supply Chain Models Examined

Central

Production 

Forecourt

Production 

Semi-Central

Production 

Delivery trucks H2 dispensing

Central SMR

Distributed SMR H2 dispensing

Semi-Central SMR H2 dispensing H2 dispensing H2 dispensing

Distribution pipe (~2 miles/station, 0.7 inch ID)
11

11

H2A Analysis, Current Technology, Central SMR Basis

• H2A Production Model values are used for production and CSD costs (N’th plant assumption in effect)

• ANL input was used for truck delivery costs

• H2A Components Model values were used for pipeline costs (2 miles, 0.7 inch ID pipeline per station)

Case

Central

SMR

Central

CHP+SMR

Forecourt

SMR

Forecourt

CHP+SMR

Semi-Central

SMR

Semi-Central

CHP+SMR

Production Capacity (kg/day) 379,387 379,387 1,500 1,500 4,500 4,500

Per-Station Dispensing Capacity (kg/day) 1,500 1,500 1,500 1,500 1,500 1,500

Production Costs ($/kg)

Capital Costs $ 0.32 $ 0.32 $ 0.58 $ 0.57 $ 0.42 $ 0.42

Fixed O&M $ 0.06 $ 0.06 $ 0.19 $ 0.19 $ 0.13 $ 0.13

Feedstock Costs $ 1.23 $ 1.13 $ 1.14 $ 1.05 $ 1.14 $ 1.05

Other Variable Costs (including utilities) $ 0.07 $ 0.07 $ 0.11 $ 0.11 $ 0.11 $ 0.11

Total $ 1.70 $ 1.59 $ 2.03 $ 1.93 $ 1.81 $ 1.72

Delivery Costs ($/kg)

Delivery Cost to Station $ 2.50 $ 2.50 $ - $ - $ 0.08 $ 0.08

Dispensing Costs ($/kg)

Compression Storage & Dispensing $ 2.46 $ 2.46 $ 2.46 $ 2.46 $ 2.46 $ 2.46

Total Cost $ 6.66 $ 6.56 $ 4.49 $ 4.40 $ 4.35 $ 4.26
12

12

H2A Analysis, Current Technology, Central SMR Basis

$6.66 $6.56 

$4.49 $4.40 $4.35 $4.26 

 $-

 $1

 $2

 $3

 $4

 $5

 $6

 $7

 $8

Central

SMR

Central

CHP+SMR

Forecourt

SMR

Forecourt

CHP+SMR

Semi-Central

SMR

Semi-Central

CHP+SMR

Cost of Hydrogen by Scenario

Production Capital Costs

Production Fixed O&M

Production Feedstock

Costs

Production Other Raw

Material Costs

Delivery Cost to Station

Compression Storage &

Dispensing Cost

Cost of dispensed hydrogen $/kg

• H2A Production Model values are used for production and CSD costs (N’th plant assumption in effect)

• ANL input was used for truck delivery costs

• H2A Components Model values were used for pipeline costs (2 miles, 0.7 inch ID pipeline per station)
13

13

H2A Analysis: Benefit of Semi-Central SMR Architecture

(Preliminary Results without CHP augmentation)

• Economies of scale benefits to SMR > cost of pipeline

• H2A Production Model values are used for production and CSD costs (N’th plant assumption in effect)

• H2A Components Model values were used for pipeline costs (2 miles, 0.7 inch ID pipeline per station)

This image cannot currently be displayed.
14

Discussion

10¢/kg is not trivial – it is in the order of magnitude of investor rate of return

8% fuel reduction = 8% reduction in GHG emissions

H2 can be distributed to nearby fueling stations (lowest cost delivery method)

- Less delivery GHG emissions & trucks on the road

- Semi-central SMR can get lower cost Natural Gas 

(industrial vs. commercial)

Leverage of economies of scale

- on-site technical support (no travel time and expense for service)

- higher up-time due to on-site technician support

- available infrastructure (natural gas, utilities, cooling)

- industrial zoning may allow easier permitting

Adiabatic flame temperature reduction = reduction in NOx emissions

- Power to Gas (P2G) can sell high-value H2 into network

- MSW gasifiers can feed into network with lower distribution cost
15

15

Questions?
16

16
17

17

$-

$2.00 

$4.00 

$6.00 

$8.00 

$10.00 

Levelized H2 Delivery Cost (2007$/kg)

Infrastructure Storage

Tube-Trailer

LH2 Truck

Pipeline

Terminal

Liquefier

Refueling Station

17

Levelized Hydrogen Delivery Cost Reduction Path

(Input from Amgad Elgowainy, ANL)

5,000 FCVs

200 kg/day Station 100,000 FCVS

600 kg/day Station 1,000,000 FCVS, 1000 kg/day Station
18

18

Source: Parker, Nathan. "Using Natural Gas Transmission Pipeline Costs to Estimate Hydrogen Pipeline Costs," Technical 

Report No. UCD-ITS-RR-04-3, Institute of Transportation Studies, University of California, Davis, January 2005.

Pipeline Cost Distribution

(Total Installed Cost)