Georgia Power begins splitting atoms inside one new Vogtle reactor



Unit 3 is expected to enter commercial operation in May or June

Georgia Power began splitting atoms on Monday to produce heat inside one of its two new nuclear units at Plant Vogtle, the company said, a key milestone that brings the country’s first new reactors built in more than three decades closer to completion.

In technical terms, the company said Unit 3′s reactor has reached a stage called “initial criticality,” meaning a self-sustaining fission reaction has started inside the unit. Georgia Power said it will continue to conduct tests as operators gradually raise the power to 100 percent, before syncing it with the grid and sending electricity out to Georgia homes and businesses.

The company said it still expects the unit to come online in May or June. The unit had been projected to enter commercial operation this month, but a series of issues discovered during startup testing in recent weeks pushed the date back.

Georgia Power president and CEO Chris Womack called the achievement an “exciting” milestone for the company and the state.

“We remain focused on safely bringing this unit online, fully addressing any issues and getting it right at every level,” Womack said in a news release. “Reaching initial criticality is one of the final steps in the startup process and has required tremendous diligence and attention to detail from our teams.”

Once online, Georgia Power says Vogtle’s two new units will generate enough electricity to power 500,000 homes and businesses. And as the effects of climate change worsen, the plant’s electricity will come without contributing heat-trapping greenhouse gas emissions.

But the project has been dogged by costly delays that could send ratepayers’ bills soaring in the years to come.

Unit 3 and its twin, Unit 4, are more than six years behind schedule and their total price tag has climbed above $35 billion, more than double what was initially forecast.

On its earnings call last month, Georgia Power’s parent, Southern Company, announced new delays in completing Unit 4. After previously projecting an in-service date by the end of 2023, the company said Unit 4 may not begin delivering electricity until the first quarter of 2024.

In a progress report filed recently with state regulators, Georgia Power also estimated it will cost $200 million more than previously thought to complete both units, bringing the company’s share of the total project cost to $10.2 billion, up from its earlier $10 billion estimate.

Georgia Power holds the largest stake in the new Vogtle units at 45.7%, followed by Oglethorpe Power — a cooperative serving utilities across the state — which owns 30%. The Municipal Electric Authority of Georgia holds 22.7%, while Dalton Utilities has the smallest share at 1.6%.

Georgia Power customers are already paying a fee in their monthly bills to cover the cost.

According to recent testimony delivered by witnesses for the Georgia Public Service Commission’s (PSC) public interest staff, the average Georgia Power customer will have paid a total of about $913 in their monthly bills for Vogtle construction by the end of this year.

As soon as Unit 3 begins generating electricity, another $3.78 rate increase approved by the PSC will begin hitting customers’ monthly bills. Additional hikes could follow, with the exact amount to be determined by the commission in hearings expected to kick off later this year.

A note of disclosure

This coverage is supported by a partnership with 1Earth Fund, the Kendeda Fund and Journalism Funding Partners. You can learn more and support our climate reporting by donating at