CO2 Battery startup Energy Dome’s 10-hour Wisconsin battery approved

July 22, 2025
LinkedIn
Twitter
Reddit
Facebook
Email

Energy Dome and Alliant Energy’s 20MW/200MWh long-duration energy storage (LDES) project in Wisconsin, US, has been approved by state regulators.

The Columbia Energy Centre project is located in Pacific, Wisconsin, close to an Alliant Energy-managed coal plant in Portage, Wisconsin.

A coalition comprising two other Wisconsin utilities—WEC Energy Group and Madison Gas & Electric—Shell Global Solutions, the US Electric Power Research Institute, and two academic institutions is working on developing the project.

The project will utilise Energy Dome’s CO2 Battery technology, which stores energy via the adiabatic compression of carbon dioxide. During charging, the gas is liquefied, and during discharging, it evaporates as part of a thermodynamic cycle.

This article requires Premium SubscriptionBasic (FREE) Subscription

Try Premium for just $1

  • Full premium access for the first month at only $1
  • Converts to an annual rate after 30 days unless cancelled
  • Cancel anytime during the trial period

Premium Benefits

  • Expert industry analysis and interviews
  • Digital access to PV Tech Power journal
  • Exclusive event discounts

Or get the full Premium subscription right away

Or continue reading this article for free

Alliant and Energy Dome signed a supply contract for the project in October 2024. The project application was filed with the regulatory Public Service Commission (PSC) of Wisconsin in August of the same year.

Construction on the 10-hour project is expected to begin in 2026 and be completed by the end of 2027.

Energy Dome is building a system of the same size in Sardinia, Italy, where the company has delivered its only commercial-scale project thus far. That 2.5MW/4MWh project went online in 2022.

Notably, the Wisconsin project was chosen by the US Department of Energy’s Office of Clean Energy Demonstrations (OCED) in 2023 to receive US$30 million in funding from a total pledge of US$325 million aimed at supporting LDES technologies.

Following this selection, the European Investment Bank (EIB) and Breakthrough Energy Ventures committed €60 million (US$65.37 million) to Energy Dome’s Sardinia project, contingent on specific conditions.

This year, it was announced that National Thermal Power Corporation (NTPC) will deploy a 20MW/160MWh Energy Dome project at a power plant in Karnataka, India

15 September 2026
San Diego, USA
You can expect to meet and network with all the key industry players again in 2025 from major US asset owners, operators, RTOs and ISOs, optimizers, software and analytics providers, technical consultancies, O&M technology providers and more.

Read Next

Premium
May 7, 2026
The business model for battery energy storage systems (BESS) in the US is changing rapidly, according to industry experts who gathered recently to discuss revenue strategies and market conditions.
May 7, 2026
Organic flow battery company CMBlu Energy has closed a €50 million (US$58.76 million) Series C financing with participation from Samsung Ventures.
May 6, 2026
US renewable energy developer, Longroad Energy’s Sun Pond solar-plus-storage project in Maricopa County, Arizona, US has reached commercial operation.
May 6, 2026
Second life battery storage firm Moment Energy has announced a US$40 million Series B funding round to accelerate its battery factory.
May 5, 2026
New South Wales BESS set two charging records on 2 May, reaching 1,240MW of charging power and capturing 11.9% of state consumption.