Play Live Radio
Next Up:
0:00 0:00
Available On Air Stations
Become a sustaining member and you could win a trip to Barbados!

Nuclear Regulators Investigate Delayed Seabrook Upgrade

Annie Ropeik/NHPR
Aerial support by Lighthawk

Federal regulators have opened a new safety investigation at Seabrook Nuclear Power Plant, focused on a component that's become an obstacle to a major new transmission line in Maine.

The New England Clean Energy Connect power line now being built in western Maine is the successor to Eversource's defunct Northern Pass, aiming to bring significant Canadian hydropower into New England – about as much as Seabrook produces in nuclear.

It's set to come online in 2023. But before it can be completed, the project's developer, Avangrid, needs Seabrook's owner, NextEra, to upgrade a substation it operates to accommodate the new line in Maine.

The substation connects Seabrook to the regional power grid and needs more capacity to handle the addition of the new electricity onto the system. In federal regulatory proceedings, Avangrid, the parent company of Central Maine Power, has accused NextEra of dragging its feet on the work.

So-called legacy generators like gas and nuclear plant owners have long opposed importing Canadian hydropower, which has the potential to lower electricity prices and cut into their profits. The Maine transmission line and Seabrook would compete on the energy markets as some of the region's largest power sources. 

Now, the Nuclear Regulatory Commission has stepped in to investigate the substation, which critics have argued could cause unexpected shutdowns at Seabrook.

NextEra spokesman Steven Stengel disputed that and said in a statement that the only reason to upgrade the substation, according to assessments by regional grid manager ISO-New England, would be to accommodate the Maine transmission line. 

"There an ongoing dispute concerning Avangrid’s refusal to fairly reimburse NextEra Energy for the financial impact of work that they have demanded the Seabrook Station perform," Stengel said.

He said the NRC investigation is a standard response to Avangrid's concerns. The nuclear plant's federal license was recently extended through 2050.

CORRECTION: An earlier version of this story incorrectly stated that the Nuclear Regulatory Commission believes the current condition of the Seabrook substation could cause unexpected shutdowns. In fact, this is an allegation from critics of the plant.

This story was updated to include comment from NextEra. 

Annie has covered the environment, energy, climate change and the Seacoast region for NHPR since 2017. She leads the newsroom's climate reporting project, By Degrees.
Related Content

You make NHPR possible.

NHPR is nonprofit and independent. We rely on readers like you to support the local, national, and international coverage on this website. Your support makes this news available to everyone.

Give today. A monthly donation of $5 makes a real difference.