Vogtle was supposed to be the beginning of a nuclear renaissance. The two AP1000's at this site were the first new reactors to be built in the USA in the 21st century. There was optimism that a novel modular design that economized space and materials would be on budget and on time. Vogtle, however, has become the poster child of the United States' inability to build affordable nuclear reactors. 
The timeline has almost doubled and the cost overrun tripled. The project bankrupted the reactor vendor Westinghouse and almost bankrupted its parent company Toshiba. Decouple veteran Mark Nelson returns to discuss what we can learn from the challenges of this megaproject.
Mark argues that Westinghouse, which had become divorced by a generation from nuclear construction, created a design that looked good on paper but presented major construction challenges. Rather than learning from contemporary successful reactor builders like the South Koreans,  the company believed it knew best. 
The design features of the AP1000 which boasted 1/5th the amount of concrete and steel of a typical reactor and modular construction were supposed to enable parallel construction and speed up the build. In reality, they resulted in unprecedented challenges such as working in confined spaces and defective modules which led to interruptions in the critical paths of the construction schedule. 
Furthermore, the engineering, procurement and construction firms engaged to build Vogtle had almost no workers or management with lived experience of building reactors let alone a first-of-a-kind novel design like the AP1000. Communication between the Chinese who were years ahead with their four AP1000 builds broke down and lessons were not shared with their American counterparts. 
The history of successful nuclear buildouts in countries like France, Japan and South Korea shows that lived construction experience and consistent designs built over and over are what bring down nuclear costs and timelines. In essence the tacit knowledge of a skilled management and workforce trumps a fancy new design especially for an atrophied nuclear sector. 
Vogtle is a cautionary tale for the western nuclear industry which has recently pinned it hopes almost exclusively on the role of advanced nuclear and novel SMR designs. Mark argues what is needed is humility, consulting with and employing the lessons of successful contemporary reactor builders, building simple reactors we are familiar with and focusing on optimizing construction ease over novel designs at least for now.