Developers plan to build a first-of-its-kind energy storage system that will set global records: ‘The expansion of energy storage infrastructure is key’

This project will be the largest energy storage system of its kind in the world.

A first-of-its-kind project for the United States has received a grant of up to $30 million from the government, the project’s developers announced.

Alliant Energy and WEC Energy Group, co-owners of Wisconsin’s Columbia Energy Center, will use the funding from the Office of Clean Energy Demonstrations to create the country’s first compressed carbon dioxide long-duration energy storage system.

The idea of the system is that it can turn carbon dioxide gas into a liquid for easier storage when energy is abundant. When energy is needed, it turns the carbon dioxide back into gas, which then powers an electricity-generating turbine.

Crucially, the setup operates as a closed-loop system, meaning that it should release no carbon dioxide and require no additional carbon dioxide after it is built out.

In addition to being first in the U.S., the Columbia Energy Storage Project will be the largest compressed carbon dioxide long-duration energy storage system in the world. A much smaller version of the same project is already operational in Sardinia, Italy. The two projects were designed by the same company, Energy Dome, which is based in Italy.

The Sardinia system has achieved an enviable 75% efficiency rate — which the much larger Wisconsin one will hope to match.

Currently, the Columbia Energy Center is Wisconsin’s largest remaining coal plant. It was supposed to be retired in 2024, but that date was pushed back to mid-2026. Its eventual transition into a much more sustainable battery storage system is good news for Wisconsinites and the planet.

“The expansion of energy storage infrastructure is key to accelerating the transition to cleaner, more sustainable renewable energy,” a spokesperson for Alliant said. “As we retire older fossil fuel facilities and add additional renewable resources to our generation portfolio, energy storage solutions help to ensure system reliability and meet customer needs.”