Utility Xcel Energy launched on Wednesday the first hybrid power plant in the United States that combines concentrating solar power and coal. The solar-coal marriage in Xcel Energy’s Cameo Generating Station near Grand Junction, Colorado is designed to lessen the need for fossil fuels to generate steam for power-generating turbines.
The plant works according to standard concentrating solar fashion, where mirrors transmit the sun’s radiant energy to a row of pipes filled with food-grade mineral oil. The sun’s rays heat it to approximately 575°F, when heat energy is redirected to heat water to about 360°F.
The solar-heated water is then transferred to the power plant’s coal-fired boiler, where it is heated further to 407°F. This process would generate the amount of steam needed to effectively spin turbine blades to create electricity.
Coal is also burned in the boiler to heat water. If water is heated before it reaches the boiler, less coal would be required to produce steam.
The hybrid plant supplements the 49-megawatt capacity of one of the Cameo’s units. The $4.5 million project is also the first to test the commercial feasibility of the solar-coal approach.
“If this project produces the successful results we expect, this type of solar thermal integration will help move the use of solar energy one step closer to being a potential technology for improving the environmental performance of coal-fired power plants,» said Kent Larson, vice president and chief energy supply officer of Xcel Energy.
The combination is projected to raise the power plant’s efficiency by as much as 5 percent while offsetting approximately 2,000 tons of carbon dioxide each year. It would also cut coal use by 900 tons annually, Xcel Energy said.
Spanish company Abengoa Solar provided eight rows of parabolic trough mirrors measuring 500 feet long. The mirrors cover a total area of about 6.4 acres.
“We believe that the solar approach being implemented at Cameo will provide a cost effective way of delivering solar energy,» said Santiago Seage, Abengoa Solar chief executive. Xcel Energy (NYSE: XEL) is a major electricity and natural gas company in the United States. It services 3.3 million electricity consumers and 1.8 million natural gas customers. The Cameo plant is the first project under Xcel Energy’s innovative technologies development program for reducing greenhouse gas emissions.