Harnessing the Wind Without a Breeze

John Davis

One of the knocks against wind energy is that you don’t have power if you don’t have wind. Well, an energy company in the Upper Midwest might have the solution.

This story from the Minneapolis (MN) Star-Tribune says Xcel Energy Inc. has teamed up with the state of Minnesota and a Virginia-based technology firm to test the first battery in the country capable of storing wind energy:

The breakthrough technology, which is the size of two semitrailer trucks stacked atop each other, was built in Japan and shipped to Luverne, Minn., where it will store electricity generated by the nearby Minwind Energy wind turbines. S&C Electric Co. expects the equipment will be completely installed by April.

The battery consists of a score of 50-kilowatt modules. When it is fully charged, the massive sodium-sulfur battery — which weighs about 80 tons — can store 7.2 megawatt-hours of electricity. That’s enough to power 500 homes for about seven hours. It will cost more than $5.4 million to buy and install the battery and analyze its performance.

The technology could help allay critics of wind energy, who lament that no electricity is produced when there’s no wind. If successful, the battery will store wind energy and release its power onto the electrical grid when the air is still.

“Energy storage is key to expanding the use of renewable energy,” Xcel Chairman and CEO Dick Kelly said. “This technology has the potential to reduce the impact caused by the variability and limited predictability of wind-energy generation.”

Xcel, has invested $3.6 million in the project and hopes that the battery will become key to its wind energy operations.