Wisconsin utilities to buy US$433m solar and storage project with 110MW BESS

LinkedIn
Twitter
Reddit
Facebook
Email

Wisconsin investor-owned utilities Madison Gas and Electric (MGE) and WEC Energy have received regulatory approval to buy a 200MW solar and 110MW battery energy storage system (BESS) in Kenosha County.

MGE and two WEC Energy subsidiaries have got the go ahead to buy the Paris Solar-Battery Park, which was developed by Invenergy and is set to become operational in 2023.

In summary:

  • MGE will own 20MW of solar and 11MW of BESS (10% of the total)
  • WE Energies will own 150MW of solar and 82.5MW of BESS (75% of the total)
  • WPS will own 30MW of solar and 16.5MW of BESS (15% of the total)

The total estimated cost of the acquisition is US$433 million according to a Final Decision filing (Docket 5-BS-254) from the Public Service Commission of Wisconsin. Wisconsin’s Citizens Utility Board has argued against the deal on the grounds it may not be the most cost-effective solution, in a brief to the commission.

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

It is MGE’s first ever battery storage which will serve its customers and the following quote from the Final Decision filing alluded to the Utility Board’s objections:

“Due to the novelty of battery storage technology for utility-scale applications, and based on the application materials, data request responses, and testimony received into the record in this proceeding, Commission staff’s financial evaluation was unable to verify the applicants support for the cost-effectiveness of acquiring 110 MW of BESS in this docket,” it read.

Energy-storage.news has asked MGE whether the park is true solar-plus-storage or just colocation with a shared connection to the grid and will update this article with their response.

A passage from the Paris solar park’s application to the Commission back in February doesn’t clarify this but gives an indication of the role the BESS will play:

“The impact to the MISO (Midcontinent Independent System Operator) grid from the integration of a BESS at Paris Solar will be positive, as the storage system can act as an “electrical suspension” system for the grid, to smooth out abrupt ups and downs in solar production that can occur on partly
cloudy days,” it read.

“The system can furnish other grid services such as frequency response, voltage support, and output scheduling to potentially shift some afternoon production to later in the day, if needed, to correspond with peak demands.”

WEC Energy aims to achieve a 55% emissions reduction by 2025 and a 70% reduction by 2030, and is investing US$2 billion in solar, wind and battery storage projects by 2025 to achieve this. Its two aforementiond subsidiaries plan to retire 1.6GW of fossil fuel generation by 2024.

It has filed a request for a similar project called to Paris called Darien which is also set to go live in 2023. That would involve more solar (250MW) but less storage (75MW) than Paris and cost around US$446 million under the same 90%/10% ownership structure between WEC and MGE. Paris’ solar portion is smaller than the initial 300MW plan announced last year.

The Midwest is behind market leaders like California and Hawaii (and to a lesser extent Texas and New York) but storage deployments could accelerate in the next few years as the region phases out coal, according to IHS Markit.

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

May 22, 2026
Battery storage developer and operator Spearmint Energy has closed a US$450 million financing to support its 300MW/600MWh Red Egret battery energy storage system (BESS) project.
May 22, 2026
Long-duration energy storage (LDES) development and investment company Frontier Power USA (FPUSA) has acquired a 480MWh battery energy storage system (BESS) portfolio from developer-operator Bimergen Energy.
May 21, 2026
In this US news roundup, OCI Energy, MN8 Energy, GridStor, and Grenergy advance battery energy storage system (BESS) projects in Texas, California, Colorado, and Georgia.
May 20, 2026
Independent power producer (IPP) Sunraycer Renewables has closed a US$901 million project financing facility, supporting three solar-plus-storage projects in Texas, US.
Premium
May 20, 2026
Energy-Storage.news speaks with Moment Energy’s CTO and co-founder Gabriel Soares, and VP of business development, Carl Mansfield, about recent updates from the second life battery company.