Basin Electric Power Cooperative, which supplies electricity to nine states, announced plans to build a coal-fired power plant in northeast Wyoming.

If approved, the new plant will be located in the Gillette area and could generate enough electricity to power about 250,000 homes, Clyde Bush, Basin's project manager, said Monday.

Plans are to have the plant generating electricity by 2011. Growth of rural areas, mineral resource development and new rural housing has increased demand for power in Basin's service area, Bush said.

"We've been studying this proposal probably for two to three years," Basin spokesman Floyd Robb said. "We need to get moving on it."

No contracts have been signed with mining companies, but the plant is expected to burn coal from Wyoming's Powder River Basin. Basin already operates a coal-fired power plant near Wheatland, Wyo.

In North Dakota, the company has power plants near Beulah and Stanton.

The new facility could cost between $500 million and $750 million, and it could have up to 200 permanent employees, Robb said.

The cost will change depending on the technology used to burn the coal, he said.

A new Wyoming plant will not affect Basin's plans to build another plant as part of an industry group, Robb said.

Montana-Dakota Utilities, Missouri River Energy Service, Minnkota Power Cooperative and Heartland Consumers Power Plant have joined Basin in considering five sites for another plant: Gascoyne and Stanton in North Dakota; Mobridge, S.D.; Yankton, S.D.; and Modale, Iowa.

Basin, based in Bismarck, generates and transmits electricity to 120 rural electric systems that serve 1.8 million customers in Wyoming, Colorado, Minnesota, Iowa, Montana, Nebraska, New Mexico, North Dakota and South Dakota.