(BURKE COUNTY, Ga.) — The Alvin W. Vogtle Electric Generating Plant, also known as Plant Vogtle, is a four-unit nuclear power plant near Waynesboro, not far from Augusta, Ga. Monday, officials at Georgia Power announced that the third of the units has safely reached 100% operating capacity.

The milestone represents the highest amount of wattage that the unit is licensed to discharge, some 1,1000 megawatts total. That much power could supply up to 500,000 home and businesses.

“Unit 3 is currently undergoing testing through the full range of plant operations, including safely running at various power levels and operating through real-life conditions just as it will over the next 60 to 80 years after the unit enters commercial operation,” said Kim Greene, chairman, president and CEO of Georgia Power in the press release. “As we enter the final stages of startup testing, reaching 100 percent power for the first time is an exciting milestone. It tells us we’re close to finishing the unit safely and bringing it online to power Georgia homes and businesses with reliable, emissions-free energy for decades to come.”

Unit 3, or Vogtle-3, is expected to enter commercial operation next month, in June 2023. Its younger sibling Vogtle-4 is already receiving its first shipments of nuclear fuel cells, a process that’s projected to wrap up later this year. After that’s complete, testing can begin.

The plant has been operational since 1989, when Vogtle-1 and Vogtle-2 were first brought online. Construction has been delayed numerous times since Vogtle-3 and Vogtle-4 were first authorized to break ground in 2009. The third unit was originally expected to begin producing power in 2016.

The AP reports that the cost of the third and fourth reactors was planned to be $14 billion, but are now on track to cost some $31 billion. And that’s before the $3.7 billion that original contractor Westinghouse paid to the owners after going bankrupt, which brings total spending to almost $35 billion.

The four co-owners of the plant, Georgia Power, Oglethorpe Power, MEAG Power and Dalton Utilities, have licensed Southern Nuclear to handle the day-to-day operations of the complex. It’s already been synchronized and hooked up to the wider electrical grid, where its electricity will be sold to municipalities and cooperatives across several southeastern states.

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