The FutureGen Alliance announced the four finalists are all in Illinois and Texas.
The winner of the FutureGen plant won't be made public until September 2007.
The power plant will convert coal into highly enriched hydrogen gas that burns more cleanly than coal and would produce electricity for homes.
FutureGen is a nonprofit collaboration among electric utilities, coal companies and others contributing to build the plant.
The project would create more than 1,000 construction jobs and as many as 200 jobs at the plant.
American Electric Power and the U-S Department of Energy are two of the investors in the project.