Battery project makes room for more rooftop solar in Decorah 

Alliant Energy to deploy new battery technology

DECORAH – July 8, 2020 – Clean, solar energy is a good thing. But it can also affect the performance and efficiency of the electric grid. An innovative battery-storage solution in Decorah, Iowa, jointly supported by Alliant Energy, US Department of Energy, and the Iowa Economic Development Authority (IEDA), looks to seamlessly connect customer-owned solar while maintaining reliable electrical service across the community.

A free DOE webinar on the project will be offered on July 30 at 12:00 p.m. CDT. Anyone interested in learning more can join by registering here

Battery storage is needed in Decorah because one electric circuit that serves the community will start to reach capacity as more customer-owned renewables are added. Until now, energy companies have had to either upgrade the grid in a community, which was expensive, or restrict the number of solar arrays that could be added in one area. Using battery storage to meet this challenge is just one of many applications which may lower customer costs.

“By working hand in hand with renewables, energy storage can contribute towards creating a cost effective, resilient, and greener grid,” said Dr. Imre Gyuk, Energy Storage Program Manager, DOE Office of Electricity. “We are pleased to be joining Alliant Energy in this project which will serve as a model for the entire country.”

“This battery project is a game-changer in Decorah,“ said Terry Kouba, President of Alliant Energy Iowa. “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.” 

“Energy storage technology presents immense opportunity to further harness and complement the state’s renewable energy resources and to foster a more efficient and resilient electric grid,” said Debi Durham, Director of IEDA and the Iowa Finance Authority. “The shared involvement by such a diverse and talented mix of partners is sure to make this project a model for lessons learned and for similar future initiatives.”

The project is jointly supported by a $250,000 cost-share from the U.S. Department of Energy, Office of Electricity (DOE-OE) and a $200,000 grant from the Iowa Economic Development Authority (IEDA). The battery will sit on land Alliant Energy leases from the City of Decorah. Sandia National Laboratories is providing technical support for the project and will collect operational data. This data is critical to inform DOE’s national energy storage research as part of the DOE-OE Stationary Energy Storage Program under the direction of Dr. Imre Gyuk. Sandia’s assistance will help to ensure that the Decorah battery is sized, integrated and operated optimally to provide the most economic benefits. Iowa State University will also study the project.

The 2.5-megawatt, 2.922-megawatt-hour 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. It will also provide valuable insight into the challenges of providing reliable and affordable electricity in areas with a concentration of customer-owned solar. Lessons learned from the Decorah pilot will inform similar, future battery projects.

DOE-OE conducts jointly supported federal-state energy storage deployment projects across the US, with deployment projects in numerous states including Massachusetts, Oregon, Hawaii, Vermont, New Mexico and Alaska, and also supports state energy storage policy development. Technical support for state storage projects and policy is provided through Sandia National Laboratories, which administers the Energy Storage Technology Advancement Partnership (ESTAP) with the assistance of the Clean Energy States Alliance (CESA). For more information about ESTAP, visit

“CESA is pleased to be part of this collaborative effort to bring a battery storage solution to Decorah, Iowa. Battery storage offers great value to Midwestern states. We hope this project will help to demonstrate that value, and that Alliant and other utilities in the region will learn from the Decorah project how to maximize value for this and future energy storage deployments,” said Todd Olinsky-Paul, Senior Project Director at the Clean Energy States Alliance.

The Decorah energy storage project is expected to be complete and in service by the end of 2020. It will be the company’s third battery storage project in Iowa. Alliant Energy has a smaller battery in a similar application near Wellman. It is also adding a battery to store energy from the company’s solar garden in Marshalltown.

About Alliant Energy
Alliant Energy’s Iowa energy company, based in Cedar Rapids, Iowa, provides regulated service to 490,000 electric and 225,000 natural gas customers. The company’s mission is to deliver the energy solutions and exceptional service customers and communities count on – safely, efficiently and responsibly. Alliant Energy (NASDAQ: LNT) is a component of the Nasdaq CRD Sustainability Index, Bloomberg’s 2019 Gender-Equality Index, and the S&P 500. For more information, visit and follow us on LinkedIn, Facebook, Instagram and Twitter.

About the Clean Energy States Alliance
The Clean Energy States Alliance (CESA) is a national, nonprofit coalition of public agencies and organizations working together to advance clean energy. CESA members—mostly state agencies— include many of the most innovative, successful, and influential public funders of clean energy initiatives in the country. Learn more at

About the Energy Storage Technology Advancement Partnership
The Energy Storage Technology Advancement Partnership (ESTAP) is a federal-state funding and information sharing project that aims to accelerate the deployment of electrical energy storage technologies in the U.S., through the creation of technical assistance and co-funding partnerships between states and the U.S. Department of Energy. ESTAP is funded by the U.S. Department of Energy, Office of Electricity (DOE-OE), managed by Sandia National Laboratories, and administered by the Clean Energy States Alliance. Learn more at