Editor’s Note: The following editorial has been updated to reflect the correction below.

As one aging nuclear power plant shuts down on Friday, ending a 47-year run, operators of one of New England's two remaining nuclear plants look ahead to 2050, when their license is now slated to expire.

When the Pilgrim nuclear plant in Plymouth ends production this week, after plant owner Entergy Corp decided the problem-plagued site is no longer financially viable, the loss of its 15% slice of New England's electrical energy production will leave a big hole in the system. Pilgrim follows Vermont Yankee, which closed in 2014, leaving  Seabrook Station as one of two nuclear plants in the region. The other is Millstone Power Station in Waterford, Connecticut.

Seabrook’s owner, NextEra Energy, recently received a 20-year license extension from the federal Nuclear Regulatory Commission, giving it a 2050 closing date. Seabrook went online in 1990, making it considerably younger than Pilgrim, but given the economic forces working against higher-priced nuclear power it’s anyone’s guess whether Seabrook will run to the end of its license. 

Efforts are ongoing to ramp up large-scale production of solar and wind energy to supplement hydro power, the other renewable source feeding New England’s power grid. But closing Pilgrim means New England consumers, for now, will rely for much of their electricity on gas-fired plants – which produced 44% of New England’s power needs in 2016 and are projected to produce about 57% by 2024.  

Closing Pilgrim means an immediate loss of power to the New England grid; replacing that power with renewables is a lengthy and costly process. ISO New England, which operates the regional power grid, plans to fill the void with 1,185 megawatts of new power from five new solar facilities and a wind power project, according to coverage by Statehouse reporter Christian Wade. But those projects are in the future, not ready to plug in now. In Salem, the gas-fired Footprint Harbor Station is a vast improvement over its coal-fired predecessor, but is still a fossil fuel operation.

The North Shore Environmental Coalition is hosting “a night to boldly envision the future” tonight, May 29, at the Beverly Public Library, with panelists from Storm Surge, the American Meteorological Society Report and an expert in New England wind power from the National Wildlife Federation. The title of the event speaks volumes about how far we have to go to break from fossil fuels, all while making up for power lost from Pilgrim’s closing. Reducing carbon emissions, which is crucial to slow global warming and more unpredictable and powerful storms, demands we rely less on natural gas and more on renewables.

The impact on our power supply as we’ve shifted away from coal-fired and nuclear power plants doesn’t come as a surprise and should have spurred more development of renewables years ago. But tough zoning regulations, problems in siting wind turbines, and the allure of affordable and readily available natural gas to produce our power have helped put New England states where they are today.

The sense of urgency is obvious to anyone paying attention to the growing risk to our coastlines, but ramping up the renewable energy supply is daunting. In 2016 the New England Climate Change Review, published at Northeastern University, quoted environmental filmmaker Robert Stone saying that, with Vermont Yankee closed and Pilgrim scheduled to close in 2019, growing reliance on natural gas was inevitable.

With the nuclear plant closures, “it’s going to be almost impossible, if not outright impossible, to completely replace the use of fossil fuels with wind and solar,” Stone said. “It’s hard to imagine it ever happening. And certainly not within the time frame that climate scientists tell us we have left to solve this problem, which is really a few decades.”

We knew long ago that closing Pilgrim would force changes in where we get our energy. Unfortunately the transition to new, sustainable sources will not be seamless, and it requires burning more fossil fuels until other alternatives are available. Massachusetts has already made a lot of progress toward changing its energy portfolio; Pilgrim’s closing should remind us all of the need to continue developing more renewable energy sources, and to do so quickly.

CORRECTION: Due to an editor’s error, an editorial published in Wednesday’s edition of The Salem News incorrectly cited the number of nuclear power plants remaining online in New England once the Pilgrim plant in Plymouth shuts down this week. Seabrook Station and Millstone Power Station in Waterford, Connecticut, remain in operation.