Xcel Energy soon will begin testing the technology to store wind energy in batteries.  It will be the first use of the technology in the United States for direct wind energy storage.

Xcel Energy will begin testing a 1MW battery-storage technology to demonstrate its ability to store wind energy and move it to the electricity grid when needed. Fully charged, the battery could power 500 homes for over 7 hours. Xcel Energy has signed a contract to purchase a battery from NGK Insulators Ltd. that will be an integral part of a project. The 20 50-kilowatt battery modules will be roughly the size of two semi trailers and weigh approximately 80 tons. They will be able to store about 7.2 megawatt-hours of electricity, with a charge/discharge capacity of 1MW. The project will take place in Luverne, MN, USA., about 30 miles east of Sioux Falls, S.D., with the battery installation beginning this spring adjacent and connected to a nearby 11MW wind farm owned by Minwind Energy, LLC. S&C Electric Company will install the battery and all associated interconnection components. The battery is expected to go on-line in October 2008. Partners in the project with Xcel Energy include the University of Minnesota, the National Renewable Energy Laboratory, the Great Plains Institute and Minwind Energy, LLC.