Particulate Matter Seminar John Kush Texas Genco Rice University Shell Center for Sustainability November 9, 2004

Who is Texas Genco?

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Texas Genco

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Formerly HL&P/Reliant Energy power plants

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11 facilities in TX; using natural gas, oil, coal, lignite and uranium fuels

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14,400 megawatts total, 12,000 in Houston area Created as result of Texas electric power industry restructuring

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Currently a subsidiary of CenterPoint Energy; sale to GC Power Acquisition, LLC in progress

W. A. Parish Station

Unit 5 6 7 1 2 3 4 8 GT W. A. Parish Unit Information MW 185 185 290 565 690 690 590 650 13 Year 1958 1958 1961 1968 1977 1978 1980 1982 1967 Primary Fuel Gas Gas Gas Gas Coal Coal Coal Coal Gas

W. A. Parish Coal Facts

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Coal Supply and Delivery

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Low sulfur western coal from the Powder River Basin in Wyoming Delivery by rail car Approx. 27,000 tons burned per day Approx. 10 million tons burned per year Arch Coal, Inc. Black Thunder Mine

W. A. Parish Station

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Emission Control Equipment

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Baghouse systems for particulate control Low sulfur coal (plus flue gas desulfurization system (FGD) on Unit 8)

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Combustion modifications for NOx control on gas-fired Units 1-4

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Low NOx burner/overfire air systems on Units 5-8

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Selective catalytic reduction (SCR) systems installed on Units 5-8 (planned for Unit 4)

W. A. Parish Emission Control Equipment

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Baghouse systems for fly ash removal

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Utilize fiberglass bags to trap fly ash

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>99.9% removal efficiency Original equipment on Unit 8; retrofit in 1988-89 on Units 5-7 to replace electrostatic precipitators Unit 5 Baghouse contains ~15,000 bags

W. A. Parish Emission Control Equipment

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Flue Gas desulfurization system (FGD) for SO2 removal on Unit 8

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Spray tower design Limestone slurry reagent SO2 removal of ~80% Unit 8 FGD System

W.A. Parish Coal Combustion Product Management

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Ash Uses

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73% of CCPs are sold

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90% of all fly ash

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100% of all FGD material 25% of all bottom ash

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CCPs are utilized as a concrete additive, stabilization and road base/foundation materials

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Ash Disposal

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Ash is classified as Class II non-hazardous waste

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Ash disposal in two on-site 30-acre industrial landfills. Design includes clay liner, cap, and groundwater monitoring

W. A. Parish NOx Control Equipment Advanced LNB/OFA systems installed on all coal units

• 1 st commercial installation of B&W LNBs on Unit 6 • 1 st commercial installation of Alstom LNB/OFA system guaranteed to meet 0.15 lb/MMBtu on WAP 7 • 50%-60% NOx reductions achieved

W. A. Parish SCR Construction

W. A. Parish Emission Control Equipment Coal unit SCR's

– Vanadium-titanium catalyst – Aqueous NH3 reagent – 80-85% reduction to meet 0.03 lb/MMBtu – All 4 SCRs operational by Spring, 2004 W. A. Parish Unit 8 SCR Retrofit Boiler SCR Fabric Filter FGD

The Steady Downward March of NOx Emission Rates W A Parish Coal Unit Regulatory NO X Limits 1 0.4

0.3

0.2

0.1

0 0.9

0.8

0.7

0.6

0.5

0.7

0.5

0.41

0.15

2003 W A Parish NOx Emissions (0.10) 0.045

0.03

WAP 5-7 Permit (1975+) WAP 8 Permit (1980) NOx RACT (1999) EPA NSPS (1998) TCEQ SIP (2004) WAP SCR Design Regulatory Limits

Texas Genco Emission Reduction Results

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W.A. Parish Emission Reductions

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Unit 8 SO2 emissions reduced by ~80% (FGD system)

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Coal-unit particulate emissions reduced by >99.9% (Baghouse system)

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Coal-unit NOx emissions reduced by ~90% (LNB/OFA + SCR systems)

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The Texas Genco system operates with one of the lowest NOx production rates in U.S. W. A. Parish coal units are now likely the lowest NOx emitting coal units in the nation.

Questions and Answers