Why are nuclear plants so expensive? Safety?s only part of the story

For many nuclear plants, they have detailed construction records, broken out by which building different materials and labor went to, and how much each of them cost. Still, the collection of sources they have allows them to make some very direct conclusions about the sources of changing costs and to build very informed models that can infer the reasons for other costs.The researchers start out with a historic analysis of plant construction in the US. There's an extensive literature about the expectation that building additional plants based on a single design will mean lower costs due to the production of standardized parts, as well as management and worker experience with the construction process. After the Three Mile Island accident, for example, regulators "required increased documentation of safety-compliant construction practices, prompting companies to develop quality assurance programs to manage the correct use and testing of safety-related equipment and nuclear construction material." Putting those programs in place and ensuring that documentation both added costs to the projects.But those were far from the only costs. All told, problems that reduced the construction efficiency contributed nearly 70 percent to the increased costs.In contrast, R&D related expenses, which included both regulatory changes and things like the identification of better materials or designs, accounted for the other third of the increases.