A Preassembled Nuclear Reactor

Continued from page 1

Two other features of the design could also cut down on operating costs. First, each reactor will be housed in a containment structure big enough to store all of the waste generated by the plant during its 60 year life span, eliminating the need for a separate storage facility. That could be especially important, as nuclear plant operators may have to store their own waste while they wait for the government to provide a permanent storage facility, which it is obliged to do by law. Second, the reactors are also designed so that fuel has to be replaced only once every five years, instead of the usual two years. That will increase the amount of time that the plant can operate.

Kadak says that small reactors make the most sense for poor countries that can't afford to finance $10 billion plants and do not have the necessary electricity grid infrastructure to distribute power from 1,000-megawatt facilities. However, at this point, it's not yet clear that the cost savings from manufacturing the reactors will be enough to convince large utilities in the United States--which can finance conventional plants--to adopt the design. "In the United States, it's a harder sell," Kadak says.

Although the new reactors are smaller than conventional ones, they use the same underlying technology--they're light water reactors--so Mowry says that it will be possible to get them certified under existing regulations. At least two other companies in the United States are developing small, modular light water reactors. One design, from Westinghouse, provided the template for combining the steam generator and the reactor, although it isn't designed to be built in a factory. A startup called NuScale also has a design for a small modular system that can be built in factories and shipped to power plants. Those reactors would generate only about 40 megawatts each. Other companies and researchers, including Kadak, are developing designs for future modular reactors using more advanced technology that will require a new regulatory process.

Mowry says that Babcock and Wilcox plans to file the official certification application in 2011. The company is already working with the Tennessee Valley Authority to start the process of evaluating a site for a plant that would use the reactor technology. Mowry says that the first plants using the technology could be up and running by 2018. But Mujid Kazimi, another professor of nuclear engineering at MIT, says that goal sounds "very ambitious" given what's known about the regulatory process.