Wind turbines line a ridge on Stetson Mountain in Washington County. A proposed transmission corridor through Aroostook County would enable additional wind power to enter the New England grid. Robert F. Bukaty/Associated Press, file
Gov. Janet Mills and federal energy officials on Tuesday extolled Maine’s potential floating offshore wind power resources that are still years in the making.
Maine’s application for a research lease for offshore wind advanced in January when the federal Bureau of Ocean Energy Management said Maine was the sole applicant for research lease on a 15.2-square mile site about 45 miles east-southeast of Portland. It’s the last step before issuing a lease for the project, known as the Maine Research Array, a small-scale project with 10 turbines capable of generating up to 144 megawatts of energy.
The project is expected to be operational and generating energy for the state by the end of the decade.
Mills told an offshore wind energy conference in Portland attended by more than 400 people that Maine benefits from deep water ports and has “room for accessible port development.”
“We have an established gateway for international trade,” she said. “The array will reinforce Maine’s leadership innovations in offshore industry while showing us how to protect ecosystems and the environment of the Gulf of Maine.”
Jeff Marootian, a principal deputy assistant secretary at the U.S. Department of Energy, told the conference that 2.8 terawatts of technical floating offshore wind potential are available in U.S. waters. A terawatt is equivalent to 1 trillion watts.
That potential represents more than twice the electricity that Americans consume now. A typical U.S. home uses 10,600 kilowatt-hours of electricity a year, according to the federal Energy Information Administration.
NEW ENERGY CORRIDOR UNDERWAY
A land-based wind project bringing power from northern Maine to ISO-New England, the region’s grid operator, has been moving ahead of offshore floating wind projects in the regulatory process.
The planned Aroostook Renewable Gateway project will consist of single-circuit and double-circuit 345 kV transmission lines and substations that will deliver 1,200 megawatts from Aroostook County to the grid, its supporters say.
Depending on the final transmission line route chosen, the Aroostook Renewable Gateway will be about 140 to 160 miles long. The transmission lines will connect two new substations, one near Glenwood Plantation and the other near either Dixmont or Detroit. The Aroostook substation was sited to provide transmission access to new large wind projects planned for northern Maine, according to backers.
An additional station, the Windsorville substation, will be built adjacent to or near the existing Coopers Mills substation for more voltage control equipment.
“We’re just getting started,” said Doug Mulvey, vice president of project development at LS Power, the corridor’s developer. “We’re trying to find one route to minimize the impact to stakeholders. We’re early in the process.”
Permit applications have not been submitted, though six public meetings have drawn 700 people, he said in a recent interview. The developers hope to submit proposals in the fall.
A citizens’ initiative passed in 2021 requires that construction of a high-voltage transmission line be approved by the Legislature, which approved the Gateway project in June. The ruling came in the wake of the highly controversial New England Clean Energy Connect Project intended to bring hydropower from Quebec to the New England grid.
The Public Utilities Commission ruled in January that Mainers should pick up part of the cost of a pair of wind-power and transmission projects bringing power from Aroostook County. Massachusetts officials had earlier directed their electric distribution companies to enter into long-term contracts for up to 40% of the transmission project’s service payments for up to 20 years. That cost sharing was crucial to the PUC’s calculus that the projects would save Maine customers money over time.
The financing required is not known, but Mulvey said it would be less than $1 billion.
Grid Strategies, a power sector consulting firm, said in a recent report that the Aroostook project is among 36 in the U.S. that, if built, would improve system resilience and reliability by increasing transmission capacity. The expansion from 22 projects in a 2021 report “reflects expanded market interest in transmission,” said the report, which was done for Americans for a Clean Energy Grid. Much of the growth is from new transmission projects to interconnect offshore wind projects in the Northeast and Mid-Atlantic, it said.
Mulvey said the project will have “immense benefits” and will save Maine ratepayers more than $3 billion during a 30-year contract.
Critics say LS Power Grid’s proposed path through Unity would affect what the Maine Department of Inland Fisheries and Wildlife has designated as an area of special ecological importance.
Aroostook County lacks a connection to New England’s electric grid and building a transmission line to bring wind power from northern Maine has been too expensive. In January, the Public Utilities Commission estimated a pair of wind-power and transmission projects would cost ratepayers $1 billion for a 60% share of the electricity output from a large wind farm.
The cost would be offset by the projects’ economic and environmental advantages, the commission said.
This story was updated at 9:30 a.m. Wednesday to correct the electricity usage of a typical home.
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