In a traditional coal-fired power plant, coal that has been pulverized into a fine dust is burned to heat water until it becomes steam. The steam then turns the blades of a large turbine, which turns the generator and produces electricity.
But if the fresh water is heated before it enters the boiler, less coal is needed in order to make the steam — and that is the principal behind Xcel Energy's brand new solar-coal hybrid power plant in western Colorado.
The $4.5 million Colorado Integrated solar Project connects thermal energy from a new parabolic-trough-concentrating solar plant built by Abengoa Solar with the steam cycle of Unit 2 at Xcel Energy's existing coal-fired Cameo Generating Station on the Colorado River near Grand Junction, Colorado. Xcel officials say it is the first actual demonstration of the concept using parabolic-trough solar technology anywhere in the world.
If this project works as we expect it to," says Marty Smith director of environmental policy at Xcel, "it would be possible to scale up the solar integration part to the point where it could possibly provide up to 10 percent of the peak generating capacity of a generating unit on a sunny day."
Xcel expects the pilot project to increase plant efficiency by three to five percent.