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Nuclear Energy

Vogtle Unit 3 Has Started Commercial Operations. What’s Next for the AP1000?

After years of schedule delays and cost overruns, the Vogtle Unit 3 nuclear generating facility has finally begun commercial operations. When the state of Georgia approved the project in 2009, the expectation was that Units 3 and 4 would cost $14 billion and begin commercial operations in 2016 and 2017, but recent estimates put the cost for the two units at over $30 billion, with Unit 4 still under construction.[1]

While the reactor should provide baseload electricity for decades to come, overall the construction experience of the first AP1000 nuclear power reactors in the United States has been a disappointing one for all parties involved. In neighboring South Carolina, a pair of AP1000s (VC Summer Units 2 and 3) were scrapped before completion after $9 billion in expenditures. This followed the 2017 bankruptcy announcement of the AP1000 designer Westinghouse, and Toshiba, which paid $5.4 billion to acquire Westinghouse in 2006, found itself saddled with billions of dollars of Westinghouse-related liabilities on account of the AP1000 projects.[2] Three other utilities spent millions of dollars to obtain combined licenses from the United States Nuclear Regulatory Commission (NRC) in order to build and operate AP1000s,[3] but those projects have not moved forward.

The AP1000, designed by the most venerable reactor designer in US history, was considered to be at the leading edge of what was billed, at the time, as the dawn of a new US nuclear energy renaissance. How did it go so wrong? And could the AP1000s get a new lease on life?

Incomplete Design, Supply Chain Issues, and More

A new report from the US Department of Energy[4] found that the root causes of the overages at Vogtle included: incomplete design, inadequate level of detail in the integrated project schedule, inadequate quality assurance, poor risk assessment, limited design constructability, a shortage of experienced labor, and even the COVID-19 pandemic. These problems, in turn, led to extensive rework and remediation, supply chain delivery issues for reactor modules, low individual productivity, and high levels of attrition and absenteeism in the workforce.

In 2018, Massachusetts Institute of Technology (MIT) assessed that successful nuclear builds tend to have seven attributes.[5] The AP1000 construction projects in Georgia and South Carolina lacked many, if not all, of those attributes. As MIT noted, two of the factors are typical for the success of first-of-a-kind projects in general, and not just nuclear ones: first, completion of needed portions of the design prior to the start of construction, and second, the development of a proven supply chain and access to a skilled labor workforce.

It has been widely reported that the AP1000s in the United States began construction before the design had been completed.[6] A 2016 report on the South Carolina project by the engineering, procurement, and construction company Bechtel found that portions of the AP1000 plant design had still not been completed as of September 2015.[7] In at least one case, new NRC requirements in 2009 related to the shield building forced design changes and resulted in delays.[8]

To give just one example of the supply chain problems that US AP1000s ran into, a Louisiana-based Shaw Nuclear Services facility, meant to be a manufacturing hub for modules that would be shipped to AP1000 construction sites, lacked experience in meeting nuclear-grade construction standards and struggled to uphold the necessary quality levels, leading to delays.[9]

Other attributes identified by MIT include: contracting structures in which all contractors and subcontractors have a vested interest in the success of the project; contract administrative processes that are rapid and non-litigious in response to unanticipated changes; a flexible regulatory environment to accommodate small, unanticipated changes to design and construction in a timely manner; the inclusion of fabricators and constructors in the design team; and the establishment of a single primary contract manager with proven experience.

Moreover, the US projects were not the first AP1000s to begin construction. For several years, Westinghouse tried to support eight first-of-a-kind, multibillion-dollar AP1000 reactor projects across the US and China at the same time. In China, Westinghouse worked with the Chinese state-owned State Nuclear Power Technology Corporation on four new reactor builds. These began construction in 2009 and 2010 at the Sanmen and Haiyang sites (Figure 1), and while they took less time than the US projects, they were also well behind schedule.

Questions Linger amid Possibly Improved Prospects for the AP1000

The next seven AP1000 projects to start operations are relatively clear, with Vogtle’s Unit 4 expected to begin commercial operations early next year and six others to follow in China. Last year, the Chinese government approved the construction of four more AP1000s at Sanmen and Haiyang,[10] the two sites with AP1000s already in operation, and two more AP1000s at the Lianjiang site.[11] Various other countries are considering the construction of AP1000s. Poland selected the AP1000 for deployment in November 2022, and has plans to begin building a plant in 2026.[12] Countries such as Bulgaria,[13] the Czech Republic,[14] and India[15] have also investigated AP1000 deployment.

This time around, AP1000 builds would have several factors going in their favor. As opposed to the initial builds, new projects would begin construction with a complete design as well as a list of suppliers able to make the needed components to the required quality assurances. In the United States, the design has now made it all the way through the NRC licensing process, which should help to avoid some of the issues and delays encountered in the first builds.

Five AP1000s in operation, with seven more on the way, are likely to grow customer confidence in terms of domestic licensing, deployment, and operation. However, the schedule and cost overruns at Vogtle and Summer will continue to hang over the AP1000’s future, especially in the United States. The costs associated with potential schedule overruns will seriously worry utilities as well as US public utility commissions—mandated to protect the ratepayer—which have witnessed the financial wreckage to utilities, electricity cost increases to ratepayers, and other associated impacts in Georgia and South Carolina. In May, Westinghouse announced it is developing a smaller reactor with a 300 MW output[16]—perhaps a tacit acknowledgment of the larger AP1000’s cloudy future.

If AP1000 construction experiences in China, Europe, or India go well, it could brighten the reactor’s future. A path back to the United States for the AP1000—if it exists—may require one or more successful construction experiences elsewhere first.

Photograph of Vogtle Units 3 and 4 courtesy of Georgia Power Company.


[1] Nuclear Newswire, “Vogtle Project Update: Cost Likely to Top $30 billion,” May 9, 2022, https://www.ans.org/news/article-3949/vogtle-project-update-cost-likely-to-top-30-billion/

[2] CNBC, “Huge Nuclear Cost Overruns Push Toshiba’s Westinghouse into Bankruptcy,” March 29, 2017, https://www.cnbc.com/2017/03/29/huge-nuclear-cost-overruns-push-toshibas-westinghouse-into-bankruptcy.html

[3] US Nuclear Regulatory Commission, “Combined License Applications for New Reactors,” accessed July 12, 2023, https://www.nrc.gov/reactors/new-reactors/large-lwr/col.html

[4] US Department of Energy, “Pathways to Commercial Liftoff: Advanced Nuclear,” March 2023, https://liftoff.energy.gov/wp-content/uploads/2023/03/20230320-Liftoff-Advanced-Nuclear-vPUB.pdf

[5] Massachusetts Institute of Technology, “The Future of Nuclear Energy in a Carbon Constrained World,” 2018, https://energy.mit.edu/wp-content/uploads/2018/09/The-Future-of-Nuclear-Energy-in-a-Carbon-Constrained-World.pdf

[6] Anya Litvak, “Westinghouse Sold an Unfinished Product, then the Problems Snowballed,” Pittsburgh Gazette, October 23, 2017, https://www.post-gazette.com/business/powersource/2017/10/23/Westinghouse-sold-an-unfinished-product-then-the-problems-snowballed/stories/201710290008

[7] Bechtel, “V.C. Summer Nuclear Generating Station Units 2 & 3: Project Assessment Report,” February 5, 2016. https://dms.psc.sc.gov/Attachments/Matter/72a1472c-5304-4f8c-aaa8-a5103cea03cc

[8] Tom Hals, Emily Flitter, “How Two Cutting Edge U.S. Nuclear Projects Bankrupted Westinghouse,” Reuters, May 2, 2017, https://www.reuters.com/article/us-toshiba-accounting-westinghouse-nucle-idUSKBN17Y0CQ

[9] Richard Korman, “Witness to the Origins of a Huge Nuclear Construction Flop,” Engineering News-Record, November 1, 2017, https://www.enr.com/articles/43325-witness-to-the-origins-of-a-huge-nuclear-construction-flop

[10] Westinghouse, “Four Additional Westinghouse AP1000 Reactors to be Built in China,” press release, April 26, 2022, https://info.westinghousenuclear.com/news/four-westinghouse-ap1000-reactors-in-china

[11] Power Technology, “Westinghouse to Add AP1000 Reactors to Nuclear Plant in China,” October 13, 2022, https://www.power-technology.com/news/westinghouse-china-nuclear/

[12] World Nuclear News, “Westinghouse, Bechtel and PEJ Push ahead on Poland AP1000,” May 26, 2023, https://www.world-nuclear-news.org/Articles/Westinghouse,-Bechtel-and-PEJ-push-ahead-on-Poland

[13] World Nuclear News, “Westinghouse Signs MoU for AP1000 in Bulgaria,” March 2, 2023, https://world-nuclear-news.org/Articles/Westinghouse-signs-MoU-for-AP1000-in-Bulgaria

[14] Westinghouse, “Westinghouse Ready to Deliver for the Czech Republic with Help from Bechtel,” November 30, 2022. https://info.westinghousenuclear.com/news/westinghouse-submits-cz-bid

[15] World Nuclear News, “Biden, Modi Affirm Commitment to Nuclear as Kovvada Plans Intensify,” June 23, 2023. https://www.world-nuclear-news.org/Articles/Biden,-Modi-affirm-commitment-to-nuclear-as-Kovvad

[16] World Nuclear News, “Westinghouse Unveils AP300 Small Modular Reactor,” May 4, 2023. https://www.world-nuclear-news.org/Articles/Westinghouse-unveils-AP300-small-modular-reactor