Thomas Hill Power Plant

Plant statistics Unit 1 - 1966 General Electric turbine Net capacity of 180 MW Coal burn rate of 2,325 tons/day Unit 2 - 1969 Westinghouse turbine Net capacity of 303 MW Coal burn rate of 3,476 tons/day Unit 3 - 1982 Westinghouse turbine Net capacity of 670 MW Coal burn rate of 8,660 tons/day

The Thomas Hill Energy Center is comprised of three electrical generating units, built from 1966 to 1982 and totaling 1,153 megawatts, and a coal mine that is actively being reclaimed after closing in 1993.

AECI employs about 260 people at the Thomas Hill Energy Center, which has received national recognition for its efficiency and successful conversion to low-sulfur coal that significantly reduced sulfur dioxide emissions. 

Currently under way is a $385 million project to construct environmental controls that will further improve air quality. Once complete by Jan. 1, 2009, the new controls will enable AECI to achieve a systemwide nitrogen oxides emission rate reduction of nearly 90 percent.

Low-sulfur coal for Thomas Hill's generating units travels 968 miles, taking about three days, from the Powder River Basin of Wyoming.

The 16.5-mile railroad spur, built in 1994 to carry Wyoming coal from a junction near Bevier to the Thomas Hill plant, was one of the longest stretches of railroad to be built in the United States since the mid-1980s.

Conveyor belts transport the coal to a crushing machine to ensure it is the right size for burning. Dust suppression systems along the route capture and recycle coal dust created in the process of crushing and transporting it.

Thomas Hill Lake was built to help cool equipment at the power plant, but the public benefits from its 1.5 billion gallons of water too. Swimming, fishing and boating are popular on the lake, which also serves as a 5,000-acre wildlife refuge.

Thomas Hill Power Plant pays several million dollars in taxes annually, helping to support local education and county services.

AECI also recycles fly ash, a byproduct of coal combustion, from its Thomas Hill Energy Center. The fly ash is extremely fine and has a calcium content of 20 percent or more, which makes it a good substitute for cement in making concrete or as a soil stabilizer.

Recycling the fly ash provides a product to industries, produces revenue that helps AECI keep its cost to members low and saves landfill space and transportation costs.

Thomas Hill plant recognized for efficiency, environmental improvements

2006 - Associated Electric Cooperative’s Thomas Hill Energy Center named Business of the Year by the Moberly Area Chamber of Commerce. The recognition was part of the chamber’s annual banquet to honor businesses and individuals in the Moberly region who make significant contributions to the region’s overall economic health.

2004 - AECI’s coal units at Thomas Hill and New Madrid power plants rank among the top 25 percent of 334 coal, oil and gas units internationally for financial performance in 2003, making them some of the lowest-cost units per megawatt-hour produced, according to the database of Solomon Associates.

January 2000 - Thomas Hill Power Division received the prestigious 1999 Delta Award presented by the Fossil Operations & Maintenance Information Service (FOMIS). The organization annually recognized a generating station from among its more than 130 clients that achieved significant improvement in operations, maintenance and personnel management over a five-year period. AECI employees at Thomas Hill were recognized for increasing the power plant’s net generation (due to the conversion to low-sulfur coal in 1994 that reduced SO2 emissions and provided sufficient fuel), cutting its operation and maintenance expenses by more than 65 percent and reducing heat rate 13.5 percent from year-end 1993 to year-end 1998.

1998 - AECI’s two coal-based plants earned a five-star ranking on the basis of heat rate, operations and maintenance costs, margin and labor efficiency in a study of 413 power plants. Only 7 percent of the plants earn the five-star rating, and Associated was one of only six utilities with two five-star plants on the list.

1998 - Thomas Hill Energy Center was spotlighted as one of five thermal steam plants with lowest production costs per megawatt-hour in the September 1998 issue of “Power Engineering.”

1996 - AECI’s “ambitious conversion” to low-sulfur coal earned its New Madrid and Thomas Hill power plants a “1996 Power Plant Award” from “Power” magazine. The national award recognized AECI’s successful conversion for environmental compliance and competitive positioning and its continuing efforts to better use low-sulfur coal as an example of “leadership in the application of fresh ideas, advanced technologies and equipment designs.”