Bolstering the future of carbon-free nuclear energy: Plant Vogtle Units 3 and 4

All images by Georgia Power Company.

Nuclear power plants are an important component of the nation’s critical infrastructure, providing a safe, reliable, and cost-effective form of energy to meet the rising demand for electricity. Georgia Power and Southern Nuclear hired Bechtel in 2017 to build the nuclear energy facilities, Units 3 and 4, at Plant Vogtle. Under this contract, Bechtel is responsible for completing construction of Vogtle Units 3 and 4 under the management of Southern Nuclear, the Southern Company subsidiary that operates the existing two units at Plant Vogtle, in Waynesboro, Ga. With the additional units, Plant Vogtle will provide always-on electricity without increasing emission of greenhouse gases to the state of Georgia and its increasing population of more than four million new residents by 2030.

When complete, the new Westinghouse AP1000 reactors will be the first new nuclear generation to be built in the United States in more than 30 years and will produce enough safe, reliable, and affordable electricity to power 500,000 Georgia homes and businesses. Vogtle Units 3 and 4 are scheduled to produce power for the citizens of Georgia in 2022 and 2023, respectively.

With more than 7,000 workers on site, and more than 800 permanent jobs available once the units begin operating, Vogtle Units 3 and 4 is currently the largest jobs-producing construction project in the state of Georgia.

Getting the Job Done

Recent milestones include:

  • Unit 3 Hot Functional Testing  Unit 3 plant systems have successfully reached normal operating pressure and temperature during hot functional testing.
  • Unit 4 Initial Energization  Plant equipment for Vogtle Unit 4 achieved initial energization and is now energized, or permanently powered. This milestone is needed to perform all subsequent testing for the unit.
  • Unit 3 Fuel Receipt – Georgia Power and Southern Nuclear received its first nuclear fuel shipment for Vogtle Unit 3. This represents the first nuclear fuel delivery for the newly designed AP1000 reactor.
  • Unit 4 Integrated Flush – The Unit 4 team began integrated flush, the testing process that pushes water through the permanent plant system piping that feeds into the reactor vessel and reactor coolant loops. This represents a critical step as the process is key to helping ensure the safe startup of Unit 4 and marks the start of extensive testing ahead for the unit’s systems.
  • Unit 4 Shield Building Roof Placement – The Bechtel-led construction team set the Vogtle Unit 4 Shield Building roof, which provides protection for the containment vessel that houses the reactor. The Unit 4 Shield Building roof weighs two million pounds, more than two fully loaded jumbo jets. It measures 135 feet in diameter and is 37 feet tall.
  • Unit 3 Condenser Vacuum – The project completed the pre-operational condenser vacuum test of the Unit 3 turbine system, which is necessary to demonstrate the steam supply and water-cooling systems operate together. In preparation for this milestone, the turbine was previously tested and rotated on its turning gear to verify it was assembled with quality and as designed.
  • Completion of Cold Hydro Testing for Unit 3 – The team 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 function as designed when under pressure.
  • Completion of Closed Vessel Testing in Unit 3 – Through closed vessel testing the team verified the pipes and valves in the Unit 3 reactor coolant system were installed as designed and helped ensure safety systems function properly.
  • Completion of the Structural Integrity Test and Integrated Leak Rate Test in Unit 3 – The project completed both tests in succession for Unit 3 and demonstrated the containment vessel meets construction quality and design requirements.
  • Placement of Final Module for Unit 3 – The Bechtel-led construction team set a massive cooling water tank on Plant Vogtle Unit 3. This was the final major lift for the Unit 3 team. The Passive Containment Cooling Water Tank module measures 35 feet tall with an outer diameter of 85 feet. The tank module, including the outfitting and rigging, weighed more than 720,000 pounds and took a year for crews to assemble at ground level. This is a major part of the AP1000 reactor’s advanced safety system and will hold approximately 750,000 gallons of water ready to flow down in the unlikely event of an emergency to help cool the reactor.
  • Placement of the Unit 3 Integrated Head Package (IHP) atop the Reactor Vessel – The Bechtel-led construction team set the IHP atop the reactor vessel in Unite 3. Standing 48 feet tall, weighing 475,000 pounds, and containing more than three miles of electrical cables, the IHP will eventually be used by highly-trained nuclear operators to monitor and control the nuclear reaction that will occur inside the Unit 3 reactor vessel.
  • Completion of Open Vessel Testing for Unit 3 – The team successfully demonstrated how water flows from the key safety systems into the reactor vessel, ensuring the paths are not blocked or constricted, and confirmed the pumps, motors, valves, pipes, and other components of the systems function as designed.
  • Unit 4 Top Head Set – The Bechtel-led construction team placed the massive reactor building dome on Unit 4. Weighing approximately 1.5 million pounds – more than two fully loaded jumbo jets – and measuring 130 feet in diameter and 37 feet tall, the dome, known as the “top head,” is the roof of the high-integrity steel structure that contains Unit 4’s nuclear reactor. It comprises 58 large plates, welded together, each more than an inch and a half thick.

Photos and Videos

Follow the progress unfolding at the site of the nation's first new nuclear units in more than 30 years through the Plant Vogtle 3 and  4 Online Photo Gallery and Georgia Power's YouTube channel.