Solar panels face the sky on Tuesday Jan. 26, 2021, in Burrillville, R.I. Credit: Elise Amendola / AP

A solar power array proposed to be built in Unity Township, Clinton and Benton would cover almost 700 acres and generate enough electricity to power 30,000 homes.

The $200 million Three Corners Solar project, which is still seeking its federal, state and local permits, is being developed by Boston-based Longroad Energy. The 110-megawatt project would produce energy by using ground-mounted solar panels to track the sun.

“It is certainly one of the larger solar development projects currently in development in Maine,” Chad Allen, the development manager for Longroad Energy, said Friday. “The Three Corners project has an opportunity to provide significant local benefits, help diversify Maine’s energy mix and help generate clean energy.”

The Three Corners project, if approved, will be significantly larger than the 76.5 megawatt solar array that went online last fall in Farmington. That project was touted as the biggest in New England. However, Allen said this may not ultimately be the new largest project in New England or Maine because there are several projects larger than 100 megawatts in the proposal stage for the region.

Solar power in Maine is growing. In 2021, the state counted almost 3,500 solar installations generating nearly 300 megawatts of electricity. That represents less than 3 percent of the electricity used in the state, but those numbers are changing, with many more solar projects in the development pipeline.

The Three Corners Solar project has been in the works since 2017, when it entered the queue for ISO-New England, the electric grid operator for the northeast region, according to Allen. A lot of the time since then has been taken up by something called an interconnection study process.

“That’s one of the important pillars of getting a project to fruition,” Allen said. “We only recently finished our system impact studies, to determine that our project can safely and reliably connect to the grid.”

The company worked hard to find the right site for the project. Developers evaluated over 18,000 acres while looking for a site that could support the solar array and be readily connected to the existing power grid.

The solar panels and other infrastructure will be sited within a 3,100-acre tract of commercial timberland owned by the Hinckley-based Bessey Development Co. The land is in the heart of Central Maine Power’s transmission system, and the utility-scale solar array will connect to the power grid via the existing Albion Road substation in Benton.

Project developers also aimed to minimize how much the project can be seen by its neighbors.

“The main constraint was finding an area that was out of sight, out of mind to the public for the most part, and avoiding wetlands,” Deron Lawrence, the senior director for natural resource permitting said last month in a virtual public information meeting about the project.  

Developers have filed state and federal permit applications for Three Corners Solar, and have started the application process in Clinton and Benton. Because Unity Township is an unorganized territory, they also need to get permission from the Maine Land Use Planning Commission, the planning and zoning authority for the unorganized areas of the state.

Allen said he doesn’t expect there will be a long wait before the company is allowed to begin building the project.  

“We expect to start construction in late summer of this year and be operational in early 2024,” he said.

But the project is not expected to last forever. It will be decommissioned in 30 years, project developers said in the informational meeting. That means the project components will be removed from the site, which will be returned to the condition it’s in today.  

The lifespan of solar projects — and what happens to the arrays after that — is something that Maine communities have begun to grapple with. Some municipalities, including Dixmont and Ellsworth, voted last fall to temporarily ban solar arrays. They cited concerns about overdevelopment and questions about what happens when the arrays reach the end of their useful lives.

Until the end of the lifespan for the Three Corners Solar project is reached, it will generate millions of dollars in new property taxes. Other benefits include a $100,000 partnership with Unity College to support internships and research, and a $25,000 donation to the Sebasticook Regional Land Trust.

“We’re really excited about both partnerships,” Allen said, adding that the company has strived to speak with a range of stakeholders in the region. “The feedback so far has been positive.”

Jack Shapiro, the climate and clean energy program director for the Natural Resources Council of Maine, said that the Three Roads Solar project sounds promising to him, too.

“Solar developments like this coming from developers like Longroad that have some roots in Maine and are thoughtful about how they [site projects] is definitely good news,” he said. “We think this has the potential to be a really great project.”

One of the benefits of a larger project like Three Roads Solar is that the developers can take advantage of economies of scale, he said, which can help push energy prices down.

“Especially in New England, where we’re seeing volatile natural gas prices, solar across the board, generally speaking, puts downward price pressure on energy costs,” Shapiro said.

Renewable energy projects such as wind and solar offer price stability because, in contrast to oil and gas, developers lock in long-term contracts for the energy that is produced there.

“These projects, they don’t just reduce pollution. They stabilize energy costs,” Shapiro said. “They do provide long-term benefits to communities and they do allow us to keep building the renewable energy infrastructure in Maine.”