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10th Annual SECA Workshop Pittsburgh, PAJuly 14-16, 2009
Integrated Gasification Fuel Cell Performance and Cost AssessmentPerformance and Cost Assessment
Presented by Phil DiPietro, Division Director
Situational Analysis and Benefits DivisionSituational Analysis and Benefits Division
Office of Systems Analyses and Planning, NETL
• Co-analystsK i ti G d– Kristin Gerdes
– Dale KeairnsDick Newby– Dick Newby
– And help and advice from Eric Grol and Jan Thijssen
2
Summary Points
• Paradigm change: Fuel cells offer higher efficiency and lower capital
• Percent CO2 capture matters: At $50/mtCO2, 100% CO2 capture saves 0.5 cents/kWh compared to 90%
3
Objective: evaluate a power plant based on fuel cell conversion of syngas as an investment optiony g p
• Scope: central station, baseload duty cycle• Assess atmospheric and pressurized fuel cell stacks• Assume DOE goals for cost and performance of the fuel
cell block• Use unit operation cost data from IGCC studiesUse unit operation cost data from IGCC studies• Include cost of CO2 storage, emissions• Quantify water use/consumptiony p
4
Configurations of Advanced Coal-Based Power PlantsIntegrated Gasification Fuel CellIntegrated Gasification
Catalytic G ifi
Oxygen plant
Integrated Gasification Fuel Cell
Slurry Oxygen
Integrated Gasification Combined Cycle
Gasifier
Syn gas cleaning
plantyGasifier
Syn gas l i
plant
cleaning
Expander
Fuel cell
cleaning
Combustion
Selexol CO2
Fuel cell
Oxy-combustion
Combustion turbine
Steam cycle
Air
Steam cycle / Expander
cycle
Power
5
CO2 Power
Sub-system Technology
Sub-system IGCC IGFC (atm) IGFC (press)
Gasifier Slurry Fed Catalytic
Gas Cleaning Dry Dry Humid
Syngas Advanced “F” Fuel cell Fuel cellSyngas Conversion
Advanced F Turbine
Fuel cell, 20 psia
Fuel cell, 270 psia
Steam Cycle Subcritical Subcritical Noney
Carbon Capture Selexol (90%) Oxy-combustion of anode off-gas (~99%)
6
Performance and Cost Summary
Conventional IGCC
IGFC (Atm SOFC)
IGFC (Press SOFC)
Efficiency (%, HHV) 32.5 49.4* 56.2**
CO EmissionsCO2 Emissions (kg CO2/MWh net) 90 6 6
Water Usage (gal/MWh net) 570 240 170(gal/MWh net)
Capital Cost (2007$/kW) 2,400 2,000 1,800
LCOE(cents/kWh) 10.2 8.8 7.9
* The efficiency without CO2 compression is 52 6%
7
The efficiency without CO2 compression is 52.6%** The efficiency without CO2 compression is 60.1%
Fuel Cell Performance Assumptions
SOFC Parameter SOFC (atm) SOFC (press)
Inlet/Outlet Temperature 650 / 800 CInlet/Outlet Temperature 650 / 800 C
Fuel Single Pass Utilization 70%
C D i 500 A/ 2Current Density 500 mA/cm2
Outlet Pressure 20 psia 270 psia
Nernst Potential* 0.84 0.92
Stack Overpotential 40 mV 50 mV
Degradation Rate 0.1% / 1,000 hrs 0.1% / 1,000 hrs
8
* Nernst calculated based on SOFC exit conditions that includes operating pressure and gas composition
Fuel Cell Cost Assumptions
• 700 $/kW AC output from the stack ($2007)I t ll d t– Installed cost
– Consistent with DOE cost targetIncludes associated heat exchangers blowers– Includes associated heat exchangers, blowers, controls and DC-to-AC rectifier
• Replacement cost assumed to be $100/kW AC output from the stack ($2007)
9
Catalytic Gasifier
• Good match with the fuel cellC l O– Consumes less O2
• ~ 0.25 kg O2 per kg coal versus ~ 0.7 for slurry fed
– Makes methaneMakes methane• 17 vol% in syngas versus ~ 0 vol% for slurry
– Uses steam
• Large area of technology risk is in catalyst recovery/regenerationy g– We use Exxon assumption of 2/3 recovery – Adds estimated 0.20 cents/kWh O&M cost
10
Oxy-combustion of Anode Off-gas
• Utilizes remaining fuel value and raises steam qualityquality
• Eliminates water gas shiftEliminates water gas shift
• Avoids “touching” CO2, enables near 100% capture
• Un-reacted oxygen in effluent is an area for future t dstudy
11
Design for High SOFC Capacity Drives System EfficiencyDrives System Efficiency
2.5
1.5
2
hr
Gas Turbine or Expanders
1
W/lb
coa
l/h Steam Turbine
SOFC
0
0.5kW Auxiliary
IGCC IGFC with atm SOFC
IGFC with press SOFC
-0.5
12
atm SOFC press. SOFC
Cost Assessment of IGFC
• Cost Approach– Fuel cell system installed
$2,500
et
IGCC with CCSFuel cell system installed
cost of $700/kW AC output from stack (2007 dollars)
– Other major unit costs $1,500
$2,000
Cos
t, $/
kW n
e IGFC (atm) with CCSIGFC (press) with CCS
$12scaled from range of studies– O&M costs and financial
parameters consistent with NETL Bituminous Baseline
$500
$1,000
Tota
l Pla
nt
$8
$10
$12
net
IGFC (atm) with CCSIGFC (press)
IGCC with CCS
NETL Bituminous Baseline Report (August 2007)
• High efficiency of IGFC and
$0
$4
$6
LCO
E, $
/kW
h
IGFC (press) with CCS
• High efficiency of IGFC and ease of CO2 capture drives down capital costs and LCOE relative to today’s IGCC t h l
$0
$2
13
technology
IGCC and IGFC Capital Costs, $/kW
IGCC IGFC Adv IGFC
Drivers of Cost DifferencesRelative to IGCC
• Catalytic Gasification (Low Temp Oxygen) (-)Gasification, ASU 1,085 620 550
Catalytic Gasification (Low Temp, Oxygen) ( )• Catalyst/Ash Handling and Coal Prep (+)• System Efficiency (-)
G Cl i 235 175 220• Sulfur Polishing (+)
H id G Cl i (Ad IGFC l ) ( )Gas Cleaning 235 175 220 • Humid Gas Cleaning (Adv IGFC only) (+)• System Efficiency (-)
Power Island 455 770 610 • Fuel Cell System (+) • Parasitic Load ( )• Parasitic Load (-)
CO2 Capture 245 135 125 • Oxycombustion v Selexol (-)• System Efficiency (-)
Balance of Plant 370 285 235 • System Efficiency (-)
Total 2 390 1 985 1 740
14
Total 2,390 1,985 1,740
IGCC and IGFC with CCS LCOE
IGCC IGFC (atm)
Adv IGFC
Drivers of Cost DifferencesRelative to IGCC
Total Plant Costs ($/kW) 2,390 1,985 1,740
Variable O&M (cents/kWh) 0.8 1.1 1.1
• Stack Replacement (+)• Gasifier Catalyst, Sorbents (+)(cents/kWh) y ( )• System Efficiency (-)
Fixed O&M, $/kW/yr 44 47 45 • Plant Size (+) • System Efficiency (-)
Fuel Cost, cents/kWh 1.9 1.2 1.1 • System Efficiency (-)
CO2 Transport and 0 35 0 25 0 20 • System Efficiency (-)Storage Cost, cents/kWh 0.35 0.25 0.20 • Percent CO2 captured (+)
LCOE (20-yr), cents/kWh 10.2 8.8 7.9
15
No
CCS
tical
CCC
SNo
CS
Subc
rit PC
N CCCC
So CS
IGCC
m)
No CCCC
SS
IGFC
(atm
s)
Gasifier WGSFGD
No
CCS
CCS
IGFC
(pre
s s FGDBFWCool Tower
0 200 400 600 800 1,000 1,200 1,400Raw Water Withdrawal
(gal/MWh net)
16
Effect of net CO2 emissions on LCOE
Coal Use Net CO2 Variable Cost Variable Cost
of CO2Platform Coal Use,
Btu/kWh Emissions, kgCO2/MWh
for Fuel, cents/kWh
Emissions @ $50/mtCO2, cents/kWh
IGCC 10,500 90 1.9 0.5
IGFC (Atm) 6,910 6 1.2 0.03
IGFC (Press) 6,070 6 1.1 0.03
PC (no capture) 9,280 860 1.6 4.3
PC (90% capture) 13,720 130 2.3 0.7
17
LCOE in a Carbon IGCC CCS IGCC no CCSIGFC (atm) CCS IGFC (atm) no CCS
Constrained Scenario
16
IGFC (atm) CCS IGFC (atm) no CCSIGFC (press) CCS IGFC (press) no CCS
IGCC, CO2 capture becomes economically preferable to no capture at
12
14
ts/k
Wh)
preferable to no capture at $30/mt CO2
Fuel cells reduce the cross 8
10
LCO
E (c
ent
over to $20/mt CO2
6
8
20-y
r
40 20 40 60 80 100
Cost for Emitted CO2, $/mt
18
2, $
Conclusions
• IGFC platforms, based on a fuel stack that meets the program goals offers both a step change inprogram goals, offers both a step change in efficiency and reduced capital cost per kW and higher percent CO2 capture and reduced water use
19
Advanced IGFC with Atmospheric SOFC and DGCNominal 50% Efficient System
air
HeatRecovery
stackgas
coal
Coal Catalyst
AshCatalyst
Separation
ash & carbon lossBlower
Dry Gas Cleaning
Particulateand Low-temp
CoolingAnode
Cathode
SOFCExpander
Oxy-Combustor
oxygen
CO2HRSG
g
Selexoland
CatalyticGasifier
HeatRecovery
steam
Treatment Separation
ash & catalyst
MercuryRemoval
Scrubbing Cooling
HeatRecovery
anodeoff-gas
Polishingoxygen
ASU
G Recovery
N2
oxy-comb O2
steam
Removal
anoderecycle gas
eductor
syngassteam addition
Recovery
air
gas
• Catalytic gasifier
O b t• Oxy-combustor
• Recycle gas eductor
20
coal
High Performance IGFC SystemNominal 60% Efficient System
Coal Catalyst
Treatment
AshCatalyst
Separation
ash & carbon loss airHeat
RecoverystackgasHRSG
Expander
CatalyticGasifier
HeatRecovery
Humid Gas Cleaning
steamAnode
Cathode
SOFC
Expander
Oxy-Comb
oxygen
CO2HRSG
expanderParticle& HCl
removal
SulfurRemoval
and
Hg & Trace
removal
oxygen
ASUN2
oxy-comb O2
steam anoderecycle
gas
polishing
eductor
air
eductorgas
• Catalytic gasifier
• Humid gas cleaning
• Pressurized SOFC
• Oxy-combustor
• Recycle gas eductor
21
y g
Atm SOFC - no CCS Atm SOFC - with CCS
10
10.5
Pres SOFC - no CCS Pres SOFC - with CCSReported Results
9
9.5
10
ts/k
Wh)
8
8.5
LCO
E (c
en
6 5
7
7.5
20-y
r
6
6.5
0.00% 0.20% 0.40% 0.60% 0.80% 1.00%
22
SOFC degradation, %/1,000 hrs