Having discovered surprising reasons why nuclear power plants are more expensive in the West, a new MIT study offers a prescription for lowering those costs.
Idaho National Laboratory Fellow David Petti said he was surprised to discover that the high cost of nuclear plants in the U.S. and Europe derives not from the reactor. Nor does it derive from the usual suspects: labor costs and regulation. Instead, MIT found that reactors cost so much in the West because of poor construction management practices.
Petti and the study make a number of recommendations to correct those.
“This is true for all plants and all technologies,” he said. “We feel without these inherent technology features, we will not get the cost reductions necessary.”
1 Standardization On Multi-Unit Sites
Like suits, nuclear plants cost more when they’re tailor made and fitted. The solution, Petti said, is serial construction of standardized plants. Plants get even cheaper with more than one unit on a single site.
“So you can set up a team and they can start construction on the first unit and then evolve to the next unit and the next unit,” he said in a briefing on the study’s findings. This is what’s been done in Japan, South Korea, and the United Arab Emirates. “If you stretch the builds out over too great a length of time, people get promoted and you start again with a new workforce. So there’s a strategy in terms of timing.”
2 Seismic Isolation
Designed to protect structures from earthquakes, seismic isolation is already used extensively in Europe, Petti said. In the U.S., a rule allowing seismic isolation is in draft form at NRC. Currently, seismic concerns are addressed late in the design process, specific to the site, Petti said, making plants more expensive. “Seismic is usually done very late in the design phase. It is very cumbersome, difficult, and it’s not as optimized as you might think because it’s done very late in the design phase and it’s so cumbersome.”
If the NRC allows seismic isolation in standardized designs, it would make plants more independent of site conditions and cheaper to build, he said.
3 Advanced Concrete
“We spent a lot of time looking at concrete,” Petti said. “There are all sorts of innovations in the world of concrete.”
Nuclear plants could benefit from innovations such as self-consolidating concrete, which eliminates the need to consolidate concrete mechanically, and new forms of concrete that are framed by steel plates and reinforced through means other than rebar.
“Pouring concrete is one of the most cost-intensive activities on the site,” Petti said. “The guys who build the form works—it’s the largest single craft on the light water reactor build.”
4. Modular construction and factory fabrication
In China it still makes sense to construct plants on-site using relatively inexpensive and highly productive local labor, Petti said, but in the United States it makes more economic sense to employ modular construction, much of which can be performed in a factory before being shipped to the plant site.
“In places where labor productivity is low and labor rates are high, modular construction and factory fabrication are a way to reduce the costs.”
Watch the lead collaborators on the MIT study give a briefing on their findings: