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Vogtle Unit 4 completes cold hydro testing

Vogtle Unit 4 completes cold hydro testing

December 7, 2022

Georgia Power today announced the completion of cold hydro testing for Vogtle Unit 4 at the nuclear expansion project near Waynesboro, Ga. The completion of cold hydro testing is required to support the last major test remaining for Unit 4, hot functional testing, which is projected to commence by the end of the first quarter of 2023.

“The team at the Vogtle 3 & 4 site continues to make important progress as we move closer to bringing online the first new nuclear units to be built in the country in over 30 years. Completion of cold hydro testing on Unit 4 is another critical milestone along the path to get us there,” said Chris Womack, chairman, president and CEO of Georgia Power. “These units are a long-term investment for our state and essential to building the future of energy for Georgia. For the next 60 to 80 years, they will help us continue to provide clean, safe, reliable and affordable energy for our customers, serving generations of Georgians as clean, emission-free sources of energy.”

Cold hydro testing on Unit 4 confirmed the reactor’s coolant system functions as designed and verified the welds, joints, pipes and other components of the coolant system and associated high-pressure systems do not leak when under pressure. As part of the testing, the reactor coolant system was filled with water and pressurized above-normal operating conditions, then lowered to normal design pressure while comprehensive inspections were conducted to verify the systems meet design standards.

Other recent milestones for Vogtle Unit 4 include:

  • Closed vessel testing (CVT) – Completed in early November, this testing process verified that the pipes and valves in the Unit 4 reactor coolant system are installed as designed and helps ensure safety systems function properly. To carry out CVT on the plant’s passive safety systems, workers installed the reactor vessel head as well as the lower and upper reactor internals and flow restrictors which will be used during hot functional testing to mimic flow through the reactor core.
  • Rotation of turbine on turning gear – Also in November, the Unit 4 Turbine was rotated on its turning gear for the first time, demonstrating the turbine was assembled with quality and that integrated oil systems function as designed. The main turbine system consists of one high-pressure turbine and three low-pressure turbines. Rotating the turbines on the turning gear ties in all the oil systems and a significant number of supporting systems in the turbine island, which is a separate structure outside of the unit’s nuclear containment building. Once operational, the turbine will rotate at 1,800 revolutions per minute, propelled by steam produced by the unit’s two steam generators using heat transferred from the nuclear reactor.  The turbine blades turn the generator rotor to produce electricity.

Following the safe loading of nuclear fuel for Vogtle Unit 3 in October, teams at the site have continued to advance through various phases of start-up testing. Vogtle Unit 3 is projected to enter service in the first quarter of 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 unit on behalf of the co-owners: Georgia Power, Oglethorpe Power, MEAG Power and Dalton Utilities.

About Georgia Power
Georgia Power is the largest electric subsidiary of Southern Company (NYSE: SO), America’s premier energy company. Value, Reliability, Customer Service and Stewardship are the cornerstones of the company’s promise to 2.7 million customers in all but four of Georgia’s 159 counties. Committed to delivering clean, safe, reliable and affordable energy at rates below the national average, Georgia Power maintains a diverse, innovative generation mix that includes nuclear, coal and natural gas, as well as renewables such as solar, hydroelectric and wind. Georgia Power focuses on delivering world-class service to its customers every day and the company is recognized by J.D. Power as an industry leader in customer satisfaction. For more information, visit www.GeorgiaPower.com and connect with the company on Facebook (Facebook.com/GeorgiaPower), Twitter (Twitter.com/GeorgiaPower) and Instagram (Instagram.com/ga_power).

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 schedule for testing for Plant Vogtle Unit 4 and 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, 2021, 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 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, 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, and challenges related to the COVID-19 pandemic; 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 and the ability of certain other Vogtle owners to tender a portion of their ownership interests to Georgia Power following certain construction cost increases, including the purported exercises by Oglethorpe Power Corporation and the City of Dalton of their tender options and 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 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.