CHARACTERISTICS

The integrated coal gasification combined cycle (IGCC) process reacts coal with high-temperature steam and an oxidant in a reducing atmosphere to form a fuel gas. The fuel gas is either passed directly to a hot-gas cleanup system to remove particulates and sulfur and nitrogen compounds, or cooled to produce steam and then cleaned conventionally. The clean fuel gas is combusted in a gas turbine generator, with residual heat in the exhaust gas recovered in a heat recovery steam generator and turbine.

More than 95% of the sulfur can be removed from coal, and 90% of the nitrogen is captured. Also, the higher thermal efficiencies of IGCC systems result in lower carbon-containing coal fuel requirements when compared to current conventional pulverized coal steam plants, resulting in lower emissions of greenhouse gases.

SIZE:
200 to 800 MW_e, modular designs of 50 to 150 MW_e may be the basis for future IGCC power plants.

FEATURES:
40% efficiency (demonstration plants)
45% efficiency (first generation commercial plant)
50% efficiency (second generation plant)

COST:
$1,200-3,000/kW for demonstration plants
$1,200-$1,900/kW for first generation plants
Less than $1,000/kW (projected) for second generation plants

CURRENT USAGE:
Approximately 10 demonstration plants in the U.S. and Europe. Several commercial plants using refinery wastes are in operation or under construction.

POTENTIAL USAGE:
IGCC has potential for new baseload generation capacity or repowering of older conventional coal-fired plants considering life extension or repowering. In the U.S. alone, potential candidates include over 100 GW of capacity that is more than 30 years old. IGCC also has potential where planned coal-fired capacity additions are subject to strict controls on sulfur and nitrogen oxide emissions.

CLIMATE CHANGE IMPACT

EMISSION EFFECT:
    

CONDITIONS FOR EMISSIONS MITIGATION:

• High efficiencies (40% demonstrated and 50% expected) will reduce carbon emissions by 27%-34% compared to conventional steam coal plants.

EMISSION ESTIMATE:
27-34% reduction from current emissions

COST-EFFECTIVENESS:
High capital costs. However, where natural gas costs are high, IGCC may be competitive.

SECONDARY EFFECTS:
Significant SO₂ and NO_x reductions; production of wastes significantly reduced; potential to safely utilize a variety of wastes, including hazardous materials.

ISSUES ASSOCIATED WITH IMPLEMENTING ACTION

• IGCC is still in demonstration and is not yet considered commercial when using coal.
• Capital costs are currently much higher than some other options.

RESOURCES

• United States Department of Energy, 1998, Clean Coal Technology Demonstration Program Project Fact Sheets 1997.
• International Energy Agency, 1993, Electric Power Technologies: Environmental Challenges and Opportunities.
• United States Department of Energy, Office of Fossil Energy, 1997, Sustainable Development with Clean Coal.

CONTACTS

Duke Energy Corp.
Victor Shellhorse
Vice President
Charlotte, NC
Tel: (704) 373-8064
Fax: (704) 373-4986
http://www.duke-energy.com

Dynegy Power Corp.
Phil Amick
Director, Gasification Development
Wabash River Coal Gasification Project
Houston, TX 77002
http://www.dynegy.com

Sierra Pacific Power Company
Jeffrey Hill
Director, Power Generation
Reno, NV
Tel: (702) 834-5650
Fax: (702) 834-5704
http://www.sierrapacific.com

TECO Power Services, Inc.
Donald E. Pless
Director, Advanced Technology
Tampa, FL
Tel: (813) 228-1111
Fax: (813) 641-5300
http://www.teco.net

U.S. Department of Energy
Gary A Nelkin
Federal Energy Technology Center
Morgantown, WV
Tel: (304) 285-4216
gnelik@fetc.doe.gov
http://www.fetc.doe.gov