The giant Mystic power plant in Everett could hold the key — especially now that it’s on the brink of closure. Owner Exelon is already retiring two smaller turbines there. The fate of its larger natural gas-fired units, Mystic 8 and 9, remains up in the air.

Just on Thursday, the CEO of grid overseer ISO New England, Gordon van Welie, said we were precariously close to rolling blackouts — “one large contingency away,” as he put it to an Associated Press reporter — during last winter’s cold snap. Yes, it’s his job to tell everyone the sky is falling; ISO’s priority is ensuring the lights stay on across the region. But his warnings are sounding starker.

Brisk enough for you yet? Try going without electricity. As the heating season arrives, the cooler weather again brings concerns that we could run out of juice on chilly days.


Chicago-based Exelon just acquired the liquefied natural gas terminal next door from French conglomerate Engie, to help ensure Mystic’s fuel source continues uninterrupted. But owning the port, formerly known as Distrigas, isn’t enough. Exelon says Mystic is no longer economic to run, and will close in 2022 without federal intervention. And if Mystic goes, the shipping terminal that has brought LNG here from foreign shores since the 1970s would likely go down with it. Mystic, after all, is its biggest customer.

ISO New England wants the Federal Energy Regulatory Commission to approve an extra charge — totaling less than $1 on our monthly electric bills — to compensate Exelon and keep Mystic going through 2024.

We dodged the bullet last winter. But we might not be so lucky if Mystic shuts down. ISO New England told FERC it would need to implement rolling blackouts if Mystic 8 and 9 are unplugged, as threatened.


Those turbines alone, with 1,700 megawatts of capacity, make Mystic the second-biggest power plant in New England, after Millstone in Connecticut. But their size isn’t the only reason to be worried. New England has become overly reliant on natural gas, the fuel behind roughly half of the region’s electricity. On cold days, most of the region’s pipeline gas gets scooped up for heating use. Mystic is different: Its operators just need to turn next door to get fuel.

ISO New England executives know this is a precarious way to live, and are working on wholesale market changes. But they say they still need this Mystic lifeline, at least through 2024.

The LNG terminal’s fate has been closely linked to Mystic’s for years, something that’s more true now that they’re under the same ownership. But ISO New England argues that we’re all counting on Mystic, not just the power plant’s neighbor.

Jon Chesto can be reached at jon.chesto@globe.com. Follow him on Twitter @jonchesto.