Unit is second Westinghouse-supplied AP1000 at delayed Georgia reactor project
The Vogtle-4 nuclear power plant in the US state of Georgia has reached first criticality, a key step during the startup testing sequence that paves the way for planned commercial operation during the second quarter of 2024.
First criticality demonstrates that – for the first time – operators have safely started the nuclear reaction inside the reactor. This means atoms are being split and nuclear heat is being made, which will be used to produce steam. A reactor achieves criticality when the nuclear fission reaction becomes self-sustaining.
Georgia Power said in a statement that operators will continue to raise power to support synchronising the plant to the grid and begin producing electricity. Then, operators will continue increasing power through multiple steps, ultimately raising power to 100%.
Vogtle-4 is the second Westinghouse AP1000 plant at the Georgia site. Vogtle-3 began commercial operation on 31 July 2023.
Vogtle-3 and -4 are the first nuclear units to be built in the US in more than three decades, but have seen cost overruns and delays.
The $14bn (€13bn) original cost of Vogtle-3 and -4 has risen to more than $30bn. The cost for Georgia Power, with a 45% share of the project, will be about $15bn.
Construction of Vogtle-3 began in March 2013 and of Vogtle-4 in November 2013. The in-service date for Vogtle-3 when the project was approved in 2012 was 2016.
In October Georgia Power said the in-service date for Vogtle-4 was being pushed back to 2024 due to a motor fault in one of four reactor coolant pumps.
Not including Vogtle-4, the US has 93 operating commercial nuclear reactors at 55 sites in 28 states. They generate about 18% of the country’s electricity. Vogtle-4 is the only unit under construction.
