US Georgia Power has announced completion of a further step in the start-up and operation of the new nuclear units (3&4) at the Vogtle nuclear expansion site. Southern Nuclear, which like Georgia Power is a subsidiary of Atlanta-based Southern Company, has submitted documentation to the Nuclear Regulatory Commission (NRC0 that is required by Southern Nuclear's Combined Operating Licence (COL). This includes all 364 inspections, tests and analyses that have been performed at unit 4 and all acceptance criteria, collectively known as ITAACs.

The company is now awaiting receipt of the 103(g) finding from the NRC documenting that licence acceptance criteria for unit 4 have been met. This will indicate that the unit has been constructed and will be operated in conformance with its COL and NRC regulations. Once this is received, no further NRC findings are necessary and Southern Nuclear can load fuel and begin the startup sequence.

Preparations for fuel loading are underway. All 157 fuel assemblies required for the operation of the unit 4 have been delivered to the site. Each fuel assembly measuring 14 feet tall was inspected and transferred to the new fuel storage racks before being placed into the used fuel pool where they will be stored until they are loaded into the reactor.

Vogtle 3, the first new reactor to start-up in the USA since 2016, was connected to the electricity grid in April and reached full power on 30 May. However, in June Georgia Power announced that commercial operation of unit 3 had been delayed because of a problem in the hydrogen system that is used to cool its main electrical generator.

Vogtle 3&4 are both 1,117 MWe Westinghouse AP1000 reactors. Units 1&2 (1,215 MWe reactors also supplied by Westinghouse) were completed in 1987 and 1989. In 2009, the US Nuclear Regulatory Authority renewed their licences for an additional 20 years. Georgia Public Service Commission approved the new reactors for the Vogtle expansion that year and construction activities began.

At that time Vogtle 3&4 were expected to cost about $14bn and to enter service in 2016 and 2017 but suffered a series of delays, including as a result of Westinghouse’s bankruptcy in 2017. The total cost of the project to build Vogtle 3&4 is now put at 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%. The units will be operated by Southern Nuclear.

Image: Vogtle 3 and 4 (courtesy of Georgia Power)