A decades-old pillar of the New England energy grid went offline Monday as the Vermont Yankee nuclear power plant shut down.

Vermont Yankee was built along the Connecticut River near Brattleboro, Vt., in the — a time when nuclear power was flourishing. Owner Entergy Corp. could have operated the plant until 2032, but financial officer Barrett Green says Vermont Yankee was priced out of the market by cheaper natural gas.

“The plant runs great," Green said. "If the plant were in a better market, we would unquestioningly be continuing to run the plant.”

Entergy says the decommissioning will cost about $1.25 billion. Vermont Yankee’s spent uranium fuel will be stored onsite in one-story-tall concrete and stainless steel cylinders that’ll have to be guarded around-the-clock for years.

As the plant closes, many of the 560 people who work there will lose their jobs. New England will be left with just three operating nuclear power plants. And the region will become more dependent on natural gas — a fuel that’s cheap in the rest of the country but getting more and more expensive here because there isn’t enough pipeline space into the region.

The escalating natural gas prices have led utilities to hike rates for consumers.