Developers eyeing the construction of a battery storage facility near Prairie Grove say they might come to the village with a formal proposal within the next few months.

California-based Eolian Energy is considering building a standalone energy-storage facility on about 52 acres off Behan Road near Snap-On Tools. The 600-megawatt utility-scale battery energy storage system, BESS for short, would use rechargeable batteries that take in and store excess energy from the electrical grid and release the energy when it is in high demand.

An exact cost estimate of the project has not yet been determined. But Eolian officials say the project “could represent up to $700 million of total investment in increasing the efficient use of the region’s power infrastructure to help save energy costs for families and businesses in the community.”

Since the idea was first publicly discussed with the Prairie Grove Village Board in December, hundreds of area residents have organized against the project, with concerns over the potential effects on safety, wildlife and the environment. Multiple tactics have been employed, including the creation of a Facebook page, a GoFundMe, an online petition and a billboard off Route 176.

Eolian representatives provided an informational webinar for residents on Wednesday night to present further details and answer questions about the project, which is called the Monarch Grid.

Why near Prairie Grove?

The site caught Eolian’s attention because of its connection to the nearby ComEd substation and high-voltage transmission systems that transfer power to Chicago and the suburbs, Eolian Project Manager Sam Lines said.

Eolian Chief Development Officer Eric Stoutenburg said the National Electric Reliability Council identified the region as a “high risk for blackouts going forward.”

“We’re trying to build infrastructure ahead of the problem, and the problem has been well defined,” he said.

Eolian officials say BESS projects help stabilize electricity costs, reduce strain on aging infrastructure and provide reliable backup power. If built, the so-called Monarch Grid could support approximately 450,000 homes during peak demand.

Though much of the land Eolian is eyeing lies in unincorporated county territory, developers are keen on seeing all of it annexed into Prairie Grove. A formal proposal to the village could be submitted “in the coming months,” Lines said.

If approved, construction could begin as early as 2028 and be completed by 2029 or 2030.

There are incentives for the village to annex the land. Eolian estimates the Monarch Grid would generate $5 million in tax revenue for its first year – approximately three times Prairie Grove’s annual property tax revenue, Lines said. After the first year, an average of $3.5 million is expected to be generated annually for the next 20 years.

In a post made on the “Prairie Grove Rural Neighbors against the Lithium Battery Project” Facebook page, Prairie Grove Village President David Underwood wrote that if the facility’s land were annexed, the village could have “a direct say in setbacks, fire protection, landscaping, emergency egress, and other aspects of the facility, shaped by resident input.”

The village could also receive an estimated $200,000 annually in property tax revenue, Underwood wrote. Annexation could also open doors to the possibility of a “new park, education center or other community facility funded by the company.”

Addressing concerns

Residents have raised concerns over the BESS project, questioning its impact on the environment, wildlife, private wells, air and soil quality and the potential risk of fires and chemical leaks.

Lines said the company has conducted multiple studies on environmental impacts through third-party engineering firms.

“All of those came up about as clean as you can expect,” Lines said. “The project, as it’s operating, will not impose any environmental danger to the local environment here, including the adjacent conservation district here.”

The U.S. Fish and Wildlife Service sent a letter confirming the Monarch Grid “would have no impact on any threatened or endangered species,” according to a statement made by Eolian officials sent to Shaw Local.

Results from the studies were not shared with the public, but will be submitted with their formal proposal, Eolian officials said.

Developers also tried to calm worries over fire safety. Lines said previous BESS fires widely covered on the news were in “outdated facilities” and “built before modern safety codes existed.” He said they plan to use lithium iron phosphate batteries, which have a solid core that wouldn’t seep into the ground if a fire did occur.

Two BESS projects are already operating in McHenry County: a 20-megawatt facility has been operating in Marengo since 2018, and another 20-megawatt facility has been operating in McHenry since 2016.

Demystifying rumors

Underwood took to the community “Prairie Grove Rural Neighbors against the Lithium Battery Project” Facebook page to address several rumors swirling around the possible project.

He again pointed to new Illinois legislation called the Clean and Reliable Grid Affordability Act, which limits counties’ ability to restrict or regulate such facilities. The new law, which goes into effect June 1, aims to add at least 3,000 megawatts of cumulative energy-storage capacity by 2030, according to the governor’s office news release.

“We cannot stop a development from being built on land outside our jurisdiction. And with Senate Bill 25 now signed into law, it is highly likely that even the county lacks the authority to stop it,” Underwood wrote.

Discussions over whether there could be a data center near the possible BESS are also raising concerns among residents. Underwood said no data center developers have approached the village with a proposal or “expressed serious interest.”

Some residents suggested the possibility that a nearby solar panel project currently under construction by School District 46 is connected to the BESS project. The school district made plans publicly in 2023 to install a solar field south of the school campus to generate electricity for the school.

“As of this time, the district has not received any proposal related to a data center, and the district’s solar project is independent of any external storage or development proposals that may be discussed within the broader community,” District 46 officials wrote in a letter to families. District 46 officials could not be reached for further comment.

Though there are “legitimate concerns” about BESS projects, Underwood wrote that “scaremongering” has “real consequences.”

“I am suggesting that the energy of this group would be far better spent working constructively with your local government as it navigates a genuinely difficult situation,” Underwood wrote.

Updates and a recording of the webinar can be found at the project’s website at monarch-grid.com. Eolian officials said they intend to schedule an in-person open house meeting in the future.