ALLIANT TO CREATE UNIQUE ENERGY STORAGE FACILITY

A first of its kind energy storage system will be coming to Wisconsin in the next few years and could serve as a blueprint for wide-scale deployment across the country.

Alliant Energy has announced it has received a $30 million federal grant for a 200-megawatt-hour storage system in Columbia County. 

According to the U.S. Department of Energy, the project would be the first to demonstrate the carbon dioxide-based energy storage system at a commercial scale. 

The Columbia Energy Storage Project will offer 10 hours of energy storage capacity by compressing carbon dioxide, or CO2, gas into a liquid, Alliant said. When energy is needed, the system converts the liquid into gas to power a turbine that generates electricity. The gas will be stored in what utility officials call an "energy dome." 

The facility is designed by an Italian company named Energy Dome, which has already worked on this technology in a smaller-scale demonstration site in Sardinia, Italy. Alliant describes the Wisconsin project as a "highly efficient, zero-emission" battery system that can power roughly 20,000 homes, and would be the first of its kind in the United States.

Mark Anderson, director of the Thermal-Hydraulics Laboratory at the University of Wisconsin-Madison, said energy storage systems will continue to be needed as clean energy sources become more widely used. That’s because renewable energy technologies — like wind and solar — primarily generate electricity when the sun is shining and the wind is blowing, he said.

"As you add these renewables that are only producing power at certain times, we need to store the energy so that we have a baseline amount of energy," Anderson said. "The more energy we can store in an environmentally friendly way, the better off we are with respect to cleaning up the environment from the power produced by our actions."

In a statement, Alliant Energy CEO John Larsen said the added storage capacity from the system in Columbia County will help strengthen the company’s generation portfolio and improve grid reliability.