(Adds comment by Southern)
May 21 (Reuters) - U.S. energy company Southern Co has delayed the startup of the third reactor at its Vogtle nuclear plant in Georgia from December until the first quarter of 2022 due to problems found during testing.
“Our current site work plan indicates a January completion date for Unit 3. While there is some flexibility in our schedule that could accelerate this timing ... a completion date during the first quarter of 2022 is expected,” the Atlanta-based company told Georgia regulators this week.
Analysts at Mizuho Group said Southern interrupted “hot functional testing” due to vibration of the plant’s pressurizer.
Southern, which last month announced Unit 3’s delay from its regulatory-approved November in-service date to December, has said it remains on track to put the fourth reactor at Vogtle into service between August 2022 and its regulatory-approved November 2022 in-service date.
The two units at Vogtle are the only big nuclear reactors under construction in the United States.
When Georgia utility regulators approved the Vogtle expansion in 2009, the two 1,117-megawatt Westinghouse AP1000 reactors were expected to cost about $14 billion and enter service in 2016 and 2017.
Some analysts estimate costs have ballooned to more than $25 billion due to delays related to the nuclear accident at Japan’s Fukushima plant in 2011 and the 2017 bankruptcy of Westinghouse, the project’s former lead contractor.
Delays and cost overruns in building reactors could make it difficult for new nuclear facilities to play much of a role in the President Joe Biden’s administration’s plan to get all of the nation’s power from non-carbon-emitting sources such as nuclear and renewables by 2035.
Southern has estimated the capital cost for its 47.5% share of the new Vogtle reactors would be about $8.7 billion. Southern has already spent about $7.6 billion as of March 31.
Reporting by Scott DiSavino; Editing by Susan Fenton and Will Dunham