Both of Louisiana's nuclear power plants have been federally relicensed to operate into the 2040s, Entergy announced Monday.

The company operates the River Bend facility in St. Francisville and Waterford 3 in Killona. Each was originally licensed in 1985. Entergy also owns the Grand Gulf plant just over the state line in Port Gibson, Mississippi; it was relicensed in 2016.

Nuclear power provides 16 percent of Louisiana's energy. It's an important component of the state's clean energy portfolio, Entergy President and CEO Phillip May wrote in a news release.

"The license renewals allow for continued safe, secure and reliable operations of Waterford 3 through 2044, and River Bend through 2045, two additional decades past the original licensing dates. The 974-megawatt River Bend facility and 1,159-megawatt Waterford unit are the largest sources of carbon-free power in Louisiana," the release states.

The plants do have to store nuclear waste on-site, which a few officials discussed when the licenses were under review. However, that's seen as a federal problem, as Nevada politicians have blocked the U.S. government from opening the Yucca Mountain repository in their state, where spent fuel rods were designed to be recycled and stored.

Entergy noted Waterford 3 and River Bend employ more than 1,500 workers and pay more than $36 million in state and local taxes each year, the company noted.

State officials had expressed hope that both nuclear plants would be allowed to continue operations. They offer a "good deal for rate payers," Louisiana Public Service Commission Chairman Eric Skrmetta said in September.

By that point, both the Nuclear Regulatory Commission and the Environmental Protection Agencies had issued favorable safety and environmental reports. The commission's final decision came in late December.

Entergy's relicensing application was under consideration as federal and state authorities began inquiries into recent power shortfalls. In January and September last year, regional energy providers struggled to meet demand. They triggered the emergency response that can lead to rolling blackouts, though neither event triggered such a drastic response.

Entergy is not specifically under investigation, though its nuclear sites were among those unable to generate maximum power output at times.

The inquiries are still underway, Federal Energy Regulatory Commission spokeswoman Mary O'Driscoll said Monday. She declined to speculate how long it would continue.

Regulators have explained that relicensure involves an examination of safety, not productivity. Consumer advocacy groups have said they just want to be cautious that utility providers are kept in check so rate payers aren't subsidizing underperforming facilities.

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