FUTURE REACTOR: The Advanced Test Reactor at Idaho National Laboratory, with a maximum capacity of 250 megawatts, would qualify as a small modular design, although it is primarily used to test nuclear components for larger reactors. Image: Courtesy of Idaho National Laboratory
Small may be beautiful for the nuclear power industry So argue a host of would-be builders of novel nuclear reactors. While the U.S. government has not given up on investing in large units that boast conventional designs, the Department of Energy has also announced the availability of $450 million in funds to support engineering and licensing of so-called "small modular reactors."
"The Obama Administration and the Energy Department are committed to an all-of-the-above energy strategy that develops every source of American energy, including nuclear power," said Secretary of Energy Steven Chu in a statement announcing the funding, which aims to get such modular reactors hooked into the grid by 2022. "The Energy Department and private industry are working to position America as the leader in advanced nuclear energy technology and manufacturing."
Globally, large reactor designs remain the predominant technology. One alternative to cut costs could be small, novel reactors, appropriate for areas with smaller electricity demands or as part of a flexible power production facility that could scale up quickly as necessary. Small reactors would have a maximum capacity of 300 megawatts of electricity, or enough to power more than 200,000 U.S. homes for a year. In addition, the reactors would be modular—made in factories and shipped to sites—to reduce costs.
But such reactors still require the same electricity-generating, safety, and waste disposal systems as the hulking light-water reactors presently being built as well as identical rigorous licensing requirements, at least in the U.S.—and that may cost them. "Yeah, there's less concrete and, yeah, there's less steel in the reactor vessel," says nuclear engineer Eric Loewen, chief consulting engineer at GE Hitachi Nuclear Energy, which is proposing a modular fast reactor to help the U.K. with its plutonium problem. But the list of other expenses associated with nuclear will not change with the new designs and "that gives pause to small modular reactors."
A modern pressurized water reactor, like the two being built in Georgia, can pump out more than 1,000 megawatts worth of power using the heat from fission to boil water to spin a turbine. Babcock & Wilcox—one-time builder of large pressurized water reactors as well as smaller ones suitable for the submarines of the U.S. Navy—would like to shrink those down to just 180 megawatts. "It's not for lack of knowledge of how to build big reactors," says Chris Mowry, president of B&W Modular Nuclear Energy.
Instead, B&W suggests that the fundamental problem facing the adoption of nuclear power is not the technology itself, but the financial risk of committing to a build a big nuclear reactor. Simply put, even the largest utilities do not have the capital to build a $7 billion reactor, and such large projects have a tendency to see costs balloon as projects are delayed. A case in point is the Tennessee Valley Authority's bid to complete a second reactor at its Watts Bar Nuclear Power Plant. The reactor, first begun in the 1970s and resumed in 2007, is behind schedule and "will cost more than forecast," admits TVA spokesman Terry Johnson. "It's a size issue," Mowry argues.