The $10 million project begun in June 2007 included the conversion of coal-fired generators in the site's A-Area to a new system that burns wood chips and tree residue.
"It looks like a standard butler building with aluminum siding, and the program is working fine," site spokesman Jim Giusti said. "It runs on wood chips like you spread in your yard. The chips go onto a conveyor belt that flows into a boiler. The material is burned up and the ash drops out into a container."
The plant operates on 22,000 tons of wood chips each year, replacing at least 12,000 tons of coal that were used by the plant.
Some of the fuel comes from U.S. Forest Service timber operations at the site, which creates an annual yield of 35 million board feet.
Residue from timber operations is substantially cheaper than coal.
The cheaper operating costs will enable the site to pay for the new facility within 10 years.