Integrating variable wind and solar power production with the needs of the power grid is an ongoing issue for the utility industry. 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.
Xcel Energy has signed a contract to purchase a battery from NGK Insulators that will be an integral part of a project. The sodium-sulfur battery is commercially available and versions of this technology are already being used in Japan and in a few US applications, according to Xcel.
Xcel noted that the twenty 50kW battery modules will be roughly the size of two semi-trailers and weigh approximately 80 tons. They will be able to store about 7.2MWh of electricity, with a charge and discharge capacity of 1MW.
The project will take place in Luverne, Minnesota, about 30 miles east of Sioux Falls, South Dakota, with the battery installation beginning this spring adjacent and connected to a nearby 11MW wind farm owned by Minwind Energy. S&C Electric Company will install the battery and all associated interconnection components. The battery is expected to go on line in October 2008.
Dick Kelly, Xcel Energy chairman and CEO, said: Energy storage is key to expanding the use of renewable energy. This technology has the potential to reduce the impact caused by the variability and limited predictability of wind energy generation. As the nation’s leader in distributing wind energy, this will be very important to both us and our customers.
