The company behind one of only two nuclear power plants under construction in the United States says it's passing on plans for another.

Georgia Power told state regulators last week that it was shelving plans for a possible new nuclear power plant in Stewart County, near Columbus. In a letter to the state Public Service Commission, the utility said it no longer saw any need for another reactor in the next few years.

In 2016, the agency had authorized Georgia Power to spent up to $99 million to study the site as part of its Integrated Resource Plan, a five-year framework for power plants. The company says it can revisit the proposal in its next plan — but for now, "the need date for new nuclear generation has moved outside the current IRP planning horizon," the company wrote.

The decision comes at a rough time for the U.S. nuclear industry, which has seen five reactors shut down in the past few years and is expecting six more to go offline in the coming decade. Cheap natural gas is pricing high-cost nuclear power plants out of deregulated electricity markets in the Northeast and Midwest, leaving the industry arguing that nuclear — which operates without producing planet-warming carbon emissions — should be subsidized like booming renewable technologies like solar and wind power.

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Georgia Power doesn't face the same competitive pressures seen in states with deregulated markets. But it's already struggling to complete a two-reactor expansion of its existing Plant Vogtle nuclear power plant near Augusta. The project, which Georgia Power is sharing with three other utilities, is running three years behind schedule and billions of dollars over budget.

Vogtle's expansion was further clouded by February's announcement of $6.3 billion in losses at the Japanese industrial conglomerate Toshiba, which owns the US nuclear company Westinghouse — which designed and is building the new reactors. The company also said it wouldn't be building any more American reactors.

Executives at Southern Company, Georgia Power's corporate parent, told stock analysts last week they expect the company to complete the Vogtle project — but that they were ready to step in and finish the job if needed. The company already operates two other nuclear plants, in Georgia and Alabama.

The Southern Alliance for Clean Energy hailed the news, calling the plan "a bad deal for the citizens of Georgia."

"The proposed Stewart County nuclear units were nothing more than financial insult to injury on the people of Georgia," Stephen Smith, the green group's executive director, said in a written statement. "We need more oversight on the runaway costs at Vogtle, not another blank check in Stewart County."

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