Unit 3 of Georgia Power’s Vogtle NPP has achieved initial criticality. "We remain focused on safely bringing this unit online, fully addressing any issues and getting it right at every level," said Chris Womack, Chairman, President & CEO of Georgia Power. He noted that Vogtle NPP would soon be a four-unit site making it the largest of its kind in the USA.

Units 1 & 2 – both 1,215 MWe reactors supplied by Westinghouse – were completed in 1987 and 1989. In 2009, the Nuclear Regulatory Commission (NRC) renewed their licences for an additional 20 years. Georgia Public Service Commission approved the new reactors for the Vogtle expansion in early 2009 and construction activities began ithe same year. At that time, the two 1,117 MWe Westinghouse AP1000 reactors were expected to cost about $14bn and to enter service in 2016 and 2017 but suffered a series of delays.

In February Georgia Power’s parent company Southern Company said unit 3 may now begin commercial operation in May or June 2023. Unit 4 will begin commercial operation sometime between November 2023 and March 2024. The total cost of the project to build Vogtle 3&4 will cost its owners more than $30bn. Georgia Power owns 45.7% of the project; Oglethorpe Power Corp owns 30%; the Municipal Electric Authority of Georgia (MEAG) owns 22.7%; and the city of Dalton owns 1.6%.

Now that the unit 3 has reached criticality, operators will continue to raise power to support synchronising the generator to the electric grid and begin producing electricity. Then, operators will continue increasing power through multiple steps, ultimately raising power to 100%. These tests are designed to ensure all systems are operating together and to validate operating procedures prior to commercial operation.

Southern Nuclear and Georgia Power, both subsidiaries of Southern Company, took over management of the construction project in 2017 following Westinghouse's Chapter 11 bankruptcy. A partnership of Cameco Corporation and Brookfield Renewable Partners is currently in the process of acquiring Westinghouse. Patrick Fragman, Westinghouse President & CEO said:. “This is a significant step toward delivering clean, reliable and safe power to the people of Georgia for generations to come.”

Image: Vogtle 3 containment (courtesy of Georgia Power)