Alexis Madrigal of Wired reports on compressed air energy storage (CAES) systems which will store compressed air deep underground. Electric power generated from wind blowing during times of low electric power demand gets used to compress air. Then the compressed air gets used to generate electric power when the demand is highest.
“CAES is the least cost, utility-scale, bulk-storage system available. If other factors such as its low environmental impact and high reliability are considered, CAES has an overwhelming advantage,” one Department of Homeland Security physicist concluded in a 2007 paper in the journal Energy (.pdf).
In the last four months, four projects have gotten new funding. In December, the rights to a long-awaited project in Norton, Ohio, were purchased by First Energy, a large utility in the area. The Norton project could store 2.7 gigawatts of power in an abandoned limestone mine.
Is that 2.7 gigawatts or 2.7 gigawatt-hours? I suspect the latter. That's equivalent to about 2 hours of electric power output from a nuclear power plant. Unfortunately no average expected cost per kilowatt-hour or efficiency numbers for these projects are provided in the article.
Can CAES make it more practical scaling up wind power to deliver a much higher percentage of total electric power? It is worth noting that electric power delivered during peak demand afternoons sells for more than electric power delivered late at night. So if the added cost of CAES isn't too great it can make wind much more competitive.
A cheap way to do electric power storage could help make some methods of generating electricity more competitive. For example, nuclear reactors running at night (when wholesale electric power rates are low) could power air compressors so that more nuclear electric power could be sold in the afternoon at higher prices.
|Share |||Randall Parker, 2010 March 14 01:46 PM Energy Electric Generators|