Columbia County may soon be home to one of the most sustainable, advanced energy storage systems in the country, according to Alliant Energy. The company announced it has been selected for a grant of up to approximately $30 million from the U.S. Department of Energy’s Office of Clean Energy Demonstrations (OCED) for a proposed 200-megawatt hour energy storage system. 

Energy Dome's CO2 battery in Sardinia, Italy

Alliant Energy’s new battery system, known as the Columbia Energy Storage Project, would be the first-of-its-kind in the United States and represents a significant advancement toward a more sustainable, reliable and cost-effective energy future.

“Guided by our purpose-driven strategy, we continue to invest in cost-effective, sustainable energy solutions for the customers and communities we proudly serve,” said John Larsen, board chair and CEO of Alliant Energy. “As we diversify our energy mix, the added capacity and unique capabilities of energy storage solutions will strengthen our generation portfolio, increase grid resilience, improve reliability and help us continue to meet customer needs. We appreciate the DOE’s support and investment in this advanced energy storage technology.”

The Columbia Energy Storage Project would utilize an innovative design by Energy Dome to deliver 10 hours of energy storage capacity by compressing carbon dioxide (CO2) gas into a liquid. When that energy is needed, the system converts the liquid CO2 back to a gas which powers a turbine to create electricity. This highly efficient, zero-emissions, closed loop battery system can power approximately 20,000 Wisconsin homes. 

According to Larsen, the unique design and capabilities of this energy storage system aligns with the company’s Clean Energy Vision goals while delivering incredible value to customers. He notes, “The Columbia Energy Storage Project is just one way we are investing in the communities we serve while building a stronger, smarter and more sustainable energy future.”

Development of the Columbia Energy Storage Project is being led by Alliant Energy in partnership with WEC Energy Group, Madison Gas and Electric, Shell Global Solutions US, Electric Power Research Institute, UW-Madison and Madison College. 

The facility will be built south of Portage, Wis. in the town of Pacific, near the current Columbia Energy Center. Alliant Energy expects to submit project plans to the Wisconsin Public Service Commission in the first half of 2024. Pending approval, project construction could begin in 2025 with completion in 2026.