Michael P. Norton
State House News Service

The federal government on Monday immediately paused the leases for large-scale offshore wind projects under construction off the U.S. coast, citing concerns about radar interference and unspecified national security risks.

The U.S. Department of the Interior made the announcement, referring too "national security risks identified by the Department of War in recently completed classified reports."

The announcement applies to the Vineyard Wind 1 project that has been moving ahead off the Nantucket coast. Project officials recently said it is delivering about 400 megawatts of energy to the New England electric grid, but Massachusetts Governor Maura Healey on Monday said it is "nearly completed" and "capable of producing 572 MW of power."

The Trump administration said the pause will give agencies time "to work with leaseholders and state partners to assess the possibility of mitigating the national security risks posed by these projects."

“The prime duty of the United States government is to protect the American people,” Interior Secretary Doug Burgum said in a written statement. “Today’s action addresses emerging national security risks, including the rapid evolution of the relevant adversary technologies, and the vulnerabilities created by large-scale offshore wind projects with proximity near our east coast population centers."

The Interior Department said following leases are paused:

Vineyard Wind 1 (OCS-A 0501)

Revolution Wind (OCS-A 0486)

CVOW — Commercial (OCS-A 0483)

Sunrise Wind (OCS-A 0487)

Empire Wind 1 (OCS-A 0512)

Governor Healey called the pause a "stop work order for five nearly complete offshore wind projects."

"Energy costs are already too high. It makes absolutely no sense for the Trump Administration to halt construction on a project that is bringing more affordable energy to our region. This puts people out of work during the holidays," Healey said in a written statement. "Donald Trump should be embracing an all-of-the-above approach to American energy, not shutting down critical sources like wind. It is dangerous to halt construction in the middle of a project, and I will stand up against this unlawful action by the Trump Administration to protect Massachusetts's ratepayers and workers. We are working closely with impacted states and developers to ensure the projects are completed and continue to provide affordable power to our communities."

Healey's office called claims about national security risks "unfounded," saying lease areas were designed in consultation with the U.S. Department of Defense, and Vineyard Wind has an agreement with the Department of Defense and the Air Force "to ensure any national security considerations are addressed."

[Editor's Note: The Trump administration has been calling the federal government's agency that oversees the military the U.S. Department of War since September 2025, thanks to an executive order from President Trump, although the agency's official name remains U.S. Department of Defense, because of a federal law passed by Congress in 1949. The Department of War existed by that name from 1789 to 1947, when it was expanded and replaced, with the new entity being known by a third name between 1947 and 1949, the National Military Establishment. In 1949 Congress changed the name of the new entity to Department of Defense.]

The governor's office said the news means that Massachusetts is "losing out on new, additional power generation that could power over 200,000 homes and businesses this winter."

"Offshore wind has its highest output in the coldest winter months when the New England grid is most constrained. Massachusetts is losing out on crucial additional power that was poised to lower costs and emissions in the region this winter. If these additional turbines are allowed to come online, Massachusetts ratepayers would save at least $13 million in direct wholesale energy market costs between January and March 2026."

The news was the latest bit of policy whiplash for the sector, which was accelerating under President Joe Biden. Even during President Trump's first term, the Department of Interior he oversaw once applauded a "BIDDING BONANZA!" for offshore wind tract leases, adding in a 2018 press release, "Trump Administration Smashes Record for Offshore Wind Auction with $405 Million in Winning Bids."

Monday's pause was announced in a press release citing "risks inherent to large-scale offshore wind projects."

"Unclassified reports from the U.S. Government have long found that the movement of massive turbine blades and the highly reflective towers create radar interference called 'clutter,' " the press release said.

"The clutter caused by offshore wind projects obscures legitimate moving targets and generates false targets in the vicinity of the wind projects," the press release said. "The Department of Energy in a 2024 report stated that a radar’s threshold for false alarm detection can be increased to reduce some clutter, but an increased detection threshold could cause the radar to 'miss actual targets.' "

The Conservation Law Foundation noted that a federal judge in State of New York v. Trump last week issued a judgment invalidating the Trump administration’s moratorium on offshore wind permitting.

"This is a desperate rerun of the Trump administration's failed attempt to kill offshore wind — an effort the courts have already rejected," said Kate Sinding Daly, senior vice president for law and policy at Conservation Law Foundation. "Many of these clean energy projects passed years of rigorous review, were upheld in court, and are moving forward. Trying again to halt these projects tramples on the rule of law, threatens jobs, and deliberately sabotages a critical industry that strengthens, not weakens, America's energy security."

The Massachusetts Fiscal Alliance said the wind projects "should be shelved in the best interest of ratepayers."

"Governor Maura Healey and her administration have championed offshore wind but that doesn’t change the fact that it is one of the most expensive forms of energy in America," alliance director Paul Craney said. "Massachusetts and New England ratepayers desperately need inexpensive, clean, reliable, American natural gas to help drive down costs, not more expensive offshore wind energy and arbitrary climate mandates."

Vineyard Wind spokesman Craig Gilvarg did not respond to questions and a request for comment.