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Battery project makes room for more rooftop solar in Decorah, Iowa

Clean solar energy is a good thing. Plus, it can positively affect the performance and efficiency of the electric grid. An innovative battery-storage solution in Decorah, Iowa, jointly supported by Alliant Energy, U.S. Department of Energy and the Iowa Economic Development Authority, looks to seamlessly connect customer-owned solar, while maintaining reliable electrical service across the community.

“This battery project is a game-changer in Decorah,” said Terry Kouba, Senior Vice President – Operations. “We’re installing it on a circuit that’s near capacity for solar. Using batteries can add critical capacity and may save our customers money, because a battery costs a fraction of the total to upgrade our system.”

The 2.5-MW, 2.922-MWh battery will serve as an “electron bank” to store excess solar power. It will store energy generated when the sun is most powerful and then release it in the evening, when demand for electricity peaks. Lessons learned from the Decorah pilot will inform similar future battery projects.

The Decorah energy storage project is expected to be complete and in service by the end of 2020. It will be our third battery storage project in Iowa.

Learn more about this project: Alliant Energy storage project will let Iowa town add more rooftop solar