Central Maine Power Co. utility lines in Pownal in October 2021. Robert F. Bukaty/Associated Press

Central Maine Power Co. will bid to build a long-stalled northern Maine electric transmission line, helped with $425 million in federal backing, the utility and the U.S. Department of Energy announced Thursday.

The 100- to 140-mile transmission line would bring 1,200 megawatts generated by wind turbines in northern Maine to New England’s grid. It’s one of four projects to be supported in the United States through a $1.5 billion federal program intended to improve grid reliability and resilience.

Avangrid Inc., CMP’s Connecticut-based parent company that will receive the Department of Energy funding, said it represents one of the largest ever federal spending programs on energy in Maine. Gov. Janet Mills called the federal commitment “unprecedented.”

The funding will be in the form of a “capacity contract,” a commitment to buy part of a transmission line’s energy capacity. It demonstrates a project’s commercial viability and reduces risk for ratepayers by reducing financial exposure, CMP said.

“Construction of this high-voltage line will also relieve transmission constraints that have stalled the development of renewable resources in northern Maine for years,” Avangrid said.

The line would run from a substation to be built in Haynesville, to an existing substation in Pittsfield, then to another existing substation in Windsor, according to the Department of Energy.

The state Public Utilities Commission terminated an agreement last December for a proposed transmission line along a similar route between the greater Augusta area and just south of Houlton. Regulators said the developer, LS Power Grid, withdrew its original fixed-price bid. LS Power countered that it submitted its proposal in March 2022, with the “reasonable expectation” of having an approved contract by Nov. 1, 2022, consistent with state law. LS Power said it held its price during a period of inflation, high interest rates and supply chain disruptions.

Doug Mulvey, vice president of project development at LS Power, was noncommittal about the company’s plans going forward. He said in an email Thursday that it will review the PUC’s request for proposal when it’s issued and will consider bidding.

LENGTHY PROCESS EXPECTED

The PUC in May initiated a process in advance of accepting bids for qualified transmission and generation projects; regulators have been seeking responses to a request for information and “indications of interest.” Comments were requested by June 21 but are not public. A PUC spokeswoman said Wednesday that the agency does not have an “anticipated date” for issuing a request for proposal. The project also must obtain state and federal permits, guaranteeing a lengthy process before construction would begin.

It’s unclear how much of the energy Maine would buy. Under the LS Power agreement that fell through, Maine was going to buy 60% of the energy generated and Massachusetts would purchase 40%.

Mills said the federal commitment will help Maine establish “energy independence that can help stabilize costs for people and strengthen our economy, which is all the more important to me for rural Maine.”

Jack Shapiro, Climate and Clean Energy Director at the Natural Resources Council of Maine, said Aroostook County’s wind resources are enormous and harnessing the energy will help end the “stranglehold of expensive and unreliable oil and gas.”

And the Maine Renewable Energy Association told the Department of Energy in March that federal backing would unlock wind power from Aroostook County at a competitive price to consumers.

Joshua Kercsmar of Preserve Rural Maine said he and others are concerned about linking the Pittsfield and Windsor substations with a 38.5-mile overhead corridor, a plan that’s included on the energy department’s website. “Given this sudden news about the project, are these landowners aware of the state’s plans?” he asked.

At the outset, the transmission line, at a cost of $1 billion, was touted for its goal of bringing clean energy generated by a proposed wind farm that would be the largest onshore wind project east of the Mississippi River. Rated at 1,000 megawatts and expected to produce nearly 3.2 billion kilowatt-hours a year, the project would generate enough electricity to power 450,000 typical homes. That’s more than half of Maine’s entire housing inventory.

PREVIOUS PLAN GENERATED OPPOSITION

The transmission line project generated opposition from residents, business owners and elected officials in some communities in northern and central Maine who insisted on changes to the transmission line’s location. Some residents said they first learned of the project in letters from LS Power about a power line strung along timberland and farmland and construction of large transmission towers. The resistance spurred one of the biggest reforms to eminent domain in Maine in 50 years, limiting forced land sales to make way for power lines and transmission towers.

Unity, which approved a temporary moratorium on transmission lines last November, adopted an ordinance Sept. 28 detailing protections for groundwater, wells, soil, wildlife and aquifers; requiring the developer to pay for environmental and other studies; and enacting additional regulations.

Jonathan Breed, a spokesperson for CMP, said the utility does not intend to use eminent domain to build the transmission system.

If Avangrid is ultimately the successful bidder, its parent company will be responsible for two transmission projects in Maine. It reported progress last summer on the New England Clean Energy Connect, a 145-mile electricity transmission line through western Maine that resumed work in October 2023.

The other three projects receiving federal energy funding from the Bipartisan Infrastructure Law are a 400-mile high-voltage transmission line in Oklahoma; a 320-mile line connecting Texas to electric grids in southeastern U.S. power markets; and a 108-mile transmission line in New Mexico.