Georgia Power says it will continue work to complete the Vogtle Units 3 and 4 nuclear reactors with Southern Nuclear serving as project manager.

In an August 31 filing with the U.S. Securities and Exchange Commission, the utility says that the most reasonable schedule for completing Plant Vogtle Units 3 and 4 is by November 2021 for Unit 3 and by November 2022 for Unit 4. It says the cost to complete the 2,134 megawatts of generating capacity is around $19 billion.

A steam generator is lowered into Vogtle Unit 3 in August 2017.Georgia Power also says that it has contracted with Bechtel to manage daily construction efforts. Bechtel will work under the direction of Southern Nuclear, the Southern Company unit that operates the existing units at Plant Vogtle.

Georgia Power owns 45.7% of the new units and has invested approximately $4.3 billion in capital costs in the project through June 2017. It estimates that its cost to complete the project is around $4.5 billion, for a total Georgia Power capital cost forecast of around $8.8 billion.

Georgia utility regulators have already approved $5.68 billion in capital costs for Georgia Power's share of the project. With $1.7 billion in anticipated payments from Toshiba, the company's potential additional capital costs are approximately $1.4 billion. Based on the new assessments, Georgia Power says the total estimated capital cost forecast for 100% of the project is around $19 billion.

The project's co-owners, Oglethorpe Power, MEAG Power and Dalton Utilities, support the recommendation, according to a statement. The recommendation is based on the results of a schedule, cost-to-complete, and cancellation assessment.

In late August, Oglethorpe Power Corp. asked the Department of Energy for as much as $1.6 billion in additional support to help finish the reactors.

Summer Ended Early

In late July, work was halted at the two-unit VC Summer nuclear site in South Carolina, the only other nuclear project under way in the U.S. Like Vogtle, the Summer project was using Westinghouse AP1000 technology. In March, Westinghouse, a unit of Toshiba, filed for Chapter 11 bankruptcy protection.

In late August, Duke Energy units in North Carolina and Florida ended plans to build new nuclear units using Westinghouse technology. Those projects were ended well before construction began, although both incurred millions of dollars in development costs.

Vogtle Project Milestones

Recent milestones include placement of the 1.4-million-pound steam generator into the Unit 3 nuclear island. Steam generators, measuring nearly 80 feet long, are heat exchangers used to convert water into steam using the heat produced in a nuclear reactor core. Each new AP1000 unit at Plant Vogtle requires two steam generators, all of which are currently on-site.

In addition, placement of the Unit 4 pressurizer compartment was completed in mid-August. The pressurizer compartment was assembled on-site and is 60 feet tall, 40 feet wide, and weighs 240,000 pounds. It will house the AP1000 pressurizer inside containment, which maintains the system pressure during operation and limits pressure transients. During the reduction or increase of plant load, the pressurizer accommodates volume changes in the reactor coolant.

Placement of the second of four accumulator tanks for the project also is complete. Accumulator tanks are spherical tanks that hold borated water inside the containment vessel within the nuclear island. In the event of a loss of reactor coolant, the tanks are designed to provide a high rate of coolant flow into the reactor for several minutes.

There are two accumulator tanks per unit with each tank weighing approximately 85,000 pounds and standing more than 17 feet tall. Fabricated in and shipped from Italy, all four accumulator tanks needed for the completion of the units are now on-site.