AEP’S emission control equipment performance better than expected

Columbus, OH, Dec. 5, 2005 — American Electric Power submitted data about the emissions performance of its generating units during the 2005 ozone season to the U.S. Environmental Protection Agency (EPA) indicating that its nitrogen oxides (NOx) reducing selective catalytic reduction (SCR) equipment is performing better than designed. AEP submits NOx emission data to the EPA as a participant in the EPA’s NOx Budget Trading Program. The EPA’s NOx Budget Trading Program is an ozone season cap-and-trade program that sets a cap on NOx emissions at a specified level. Sources are provided allowances (each allowance represents one ton of emissions) and each year the source must hold sufficient allowances to cover all NOx tons emitted by the source during the ozone season. Ground-level ozone, or smog, is formed from NOx and volatile organic compounds (VOCs) in the presence of sunlight and heat. Levels are highest during the hot summer months when sunlight is strongest.

Between May 1 and Sept. 30, 2005, AEP’s 50 coal-fired generating units, located in the 22 state regional NOx control area, emitted 45,945 tons of NOx while generating 54,641,950 megawatthours (MWh) of electricity. Between May 1 and Sept. 30, 2004, those same units emitted 58,698 tons of NOx while generating 51,787,843 MWh of electricity. As comparison, in 2000, before installation of SCR equipment on AEP’s coal-fired plants, AEP emitted 145,762 tons of NOx between May 1 and Sept. 30 while generating 51,827,692 MWh of electricity.

AEP has been operating SCR systems on coal-fired generating units since 2001 and currently has SCR systems installed on 9,742 megawatts of coal-fired generation (14 generating units at eight plant sites). The company also operates low-NOx burners and other combustion control technologies that reduce NOx emissions at all of its other coal-fired plants. AEP’s SCR systems are designed to reduce NOx emissions by up to 90 percent; however, a majority of AEP’s SCR units achieve better than design and industry standards by consistently achieving NOx reductions of 92 to 94 percent.

AEP will invest an additional $310 million by 2010 to further reduce NOx emissions. This investment includes installations of SCR systems on an additional 1,939 megawatts of generation (three generating units at two plant sites) by 2009.

AEP also has made significant investment to reduce SO2 emissions, including installation of flue-gas desulfurization systems, commonly called scrubbers, on 5,061 megawatts of coal- or lignite-fired generation (eight units at six plant sites). After already spending more than $1 billion to reduce SO2 emissions since the mid-1990s, AEP will invest another $3.3 billion before 2010 to make even deeper cuts in SO2 emissions. AEP will install scrubbers on an additional 8,751 megawatts of coal-fired generation (14 generating units at eight plant sites) by 2010.

In addition to its retrofit program to reduce NOx, sulfur dioxide (SO2) and mercury emissions on its current generating fleet, AEP also has committed to build the first large-scale, base-load Integrated Gasification Combined Cycle clean-coal generating plant as soon as 2010. IGCC technology converts coal into a synthetic gas before it is burned. The process results in fewer emissions, and carbon capture and sequestration is expected to be easier from an IGCC plant than from a pulverized coal plant.

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