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Vogtle Unit 3 reaches initial criticality

March 6, 2023

Georgia Power today announced that Vogtle Unit 3 has safely reached initial criticality. Initial criticality is a key step during the startup testing sequence and 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. Achieving initial criticality is necessary to continue the startup of the Unit in order to generate sufficient heat for the production of electricity.

“We remain focused on safely bringing this unit online, fully addressing any issues and getting it right at every level. Reaching initial criticality is one of the final steps in the startup process and has required tremendous diligence and attention to detail from our teams,” said Chris Womack, chairman, president and CEO of Georgia Power. “When you consider the history of safe and reliable operations at Vogtle Units 1 and 2 for decades now, it puts today’s milestone in perspective that Plant Vogtle will be a four-unit site making it the largest of its kind in the U.S. This is a truly exciting time as we prepare to bring online a new nuclear unit that will serve our state with clean and emission-free energy for the next 60 to 80 years.” 

Vogtle Unit 3 continues with startup testing which demonstrates the integrated operation of the primary coolant system and steam supply system at design temperature and pressure with fuel inside the reactor. Now that the Unit 3 reactor has reached criticality, operators will continue to raise power to support synchronizing the generator to the electric grid and begin producing electricity. Then, operators will continue increasing power through multiple steps, ultimately raising power to 100 percent. These tests are designed to ensure all systems are operating together and to validate operating procedures prior to declaration of Commercial Operation. The in-service date for Unit 3 is projected during May or June 2023.

The new Vogtle units are an essential part of Georgia Power's commitment to delivering clean, safe, reliable and affordable energy to its 2.7 million customers. Once operating, the two new units, which will be clean energy sources that produce zero air pollution, are expected to power more than 500,000 homes and businesses. Southern Nuclear will operate the new units on behalf of the co-owners: Georgia Power, Oglethorpe Power, MEAG Power and Dalton Utilities.

 

Cautionary Note Regarding Forward-Looking Statements

Certain information contained in this release is forward-looking information based on current expectations and plans that involve risks and uncertainties. Forward-looking information includes, among other things, statements concerning the projected in-service date for Plant Vogtle Unit 3. Georgia Power cautions that there are certain factors that can cause actual results to differ materially from the forward-looking information that has been provided. The reader is cautioned not to put undue reliance on this forward-looking information, which is not a guarantee of future performance and is subject to a number of uncertainties and other factors, many of which are outside the control of Georgia Power; accordingly, there can be no assurance that such suggested results will be realized. The following factors, in addition to those discussed in Georgia Power's Annual Report on Form 10-K for the year ended December 31, 2022, and subsequent securities filings, could cause actual results to differ materially from management expectations as suggested by such forward-looking information: the potential effects of the continued COVID-19 pandemic; the ability to control costs and avoid cost and schedule overruns during the development, construction, and operation of facilities or other projects, including Plant Vogtle Units 3 and 4, which includes components based on new technology that only within the last few years began initial operation in the global nuclear industry at this scale, due to current and/or future challenges which include, but are not limited to, changes in labor costs, availability and productivity, challenges with the management of contractors or vendors, subcontractor performance, adverse weather conditions, shortages, delays, increased costs, or inconsistent quality of equipment, materials, and labor, contractor or supplier delay, the impacts of inflation, delays due to judicial or regulatory action, nonperformance under construction, operating, or other agreements, operational readiness, including specialized operator training and required site safety programs, engineering or design problems or any remediation related thereto, design and other licensing-based compliance matters, including, for Plant Vogtle Unit 4, inspections and the timely submittal by Southern Nuclear of the Inspections, Tests, Analyses, and Acceptance Criteria documentation and the related investigations, reviews and approvals by the NRC necessary to support NRC authorization to load fuel, challenges with start-up activities, including major equipment failure, or system integration, and/or operational performance, continued challenges related to the COVID-19 pandemic or future pandemic health events, continued public and policymaker support for projects, environmental and geological conditions, delays or increased costs to interconnect facilities to transmission grids, and increased financing costs as a result of changes in market interest rates or as a result of project delays; the ability to overcome or mitigate the current challenges at Plant Vogtle Units 3 and 4 that could further impact the cost and schedule for the project; legal proceedings and regulatory approvals and actions related to construction projects, such as Plant Vogtle Units 3 and 4, including Public Service Commission approvals and NRC actions; under certain specified circumstances, a decision by holders of more than 10% of the ownership interests of Plant Vogtle Units 3 and 4 not to proceed with construction; the notice of tender by Oglethorpe Power Corporation and the City of Dalton of a portion of their ownership interests in Plant Vogtle Units 3 and 4 to Georgia Power, including related litigation; the ability to construct facilities in accordance with the requirements of permits and licenses (including satisfaction of NRC requirements), to satisfy any environmental performance standards and the requirements of tax credits and other incentives, and to integrate facilities into the Southern Company system upon completion of construction; the inherent risks involved in operating and constructing nuclear generating facilities; the ability of counterparties of Georgia Power to make payments as and when due and to perform as required; the direct or indirect effect on Georgia Power's business resulting from cyber intrusion or physical attack and the threat of cyber and physical attacks; catastrophic events such as fires, earthquakes, explosions, floods, tornadoes, hurricanes and other storms, droughts, pandemic health events, political unrest, wars or other similar occurrences; and the direct or indirect effects on Georgia Power's business resulting from incidents affecting the U.S. electric grid or operation of generating or storage resources. Georgia Power expressly disclaims any obligation to update any forward–looking information.