Georgia Power Co. increased its share of the projected capital and construction costs for the Alvin W. Vogtle nuclear expansion project to $8.4 billion from $7.3 billion.

The revision is based on Southern Nuclear Operating Co.'s new cost-to-complete estimate, after Georgia Power and its corporate affiliate made a series of decisions like increasing field supervision and engineering oversight to lower project risk and maintain project momentum. Georgia Power and Southern Nuclear assumed project management from original contractor Westinghouse Electric Co. LLC after it declared bankruptcy in March 2017.

The Southern Co. subsidiary said it will absorb the $700 million in additional projected costs and will not seek recovery of those future costs from its ratepayers, according to an Aug. 8 news release. While the projected costs are "reasonable, necessary and prudent," Georgia Power has decided not to ask the state Public Service Commission to approve those costs so soon.

State regulators approved the company's previous capital forecast in 2017 and its staffers recently said they want more disclosures from the company on the project.

The company said it may present an increased contingency of approximately $400 million to the state PSC for evaluation "as and when appropriate in the future."

"While there will always be challenges in building the first new nuclear units in this country in more than 30 years, we remain focused on reducing project risk and maintaining the current project momentum in order to provide our customers with a new carbon-free energy source that will put downward pressure on rates for 60 to 80 years," Georgia Power Chairman, President and CEO Paul Bowers said.

Units 3 and 4 are still slated to be completed by the revised in-service dates of November 2021 and November 2022, respectively.

Aside from Georgia Power, owners of the Vogtle expansion project include Oglethorpe Power Corp., Municipal Electric Authority of Georgia and Dalton Utilities.