Are Tiny Nuclear Reactors The Power Plant Of The Future?

They’re easy and cheap to build, ostensibly safer, and more portable: A fleet of small nuclear reactors about the size of a train car might be what powers us in the future.

Many environmentalists, and indeed countries, are dead-set against nuclear power, believing the safety risks trump all. But for others, the question–given the need need to cut carbon, and generate more electricity in the future–is not whether nuclear is necessary, but how to do it safely and at reasonable cost.


One answer could be to invest big in small plants, known as small “modular” nuclear reactors (SMRs) that are about the size of rail cars, and have an output of less than 300 MW. We’ve written about SMRs before, but now, according to a new report by the Energy Policy Institute at the University of Chicago, SMRs are getting closer to adoption. And it’s easy to see why: They cost a tenth of large plants, are easier to construct, and would give a jolt to the economy if they were developed here in the U.S.

“Clearly, a robust U.S. commercial SMR industry is highly advantageous to many sectors,” the report concludes. “It would be a huge stimulus for high-valued job growth, restore U.S. leadership in nuclear reactor technology, and, most importantly, strengthen U.S. leadership in a post-Fukushima world, on matters of nuclear safety, nuclear security, nonproliferation, and nuclear waste management.”

SMRs are built using factory-made components, then shipped in pieces to sites, and assembled. Larger plants, by contrast, often involve many bespoke elements, which increase their complexity and up the potential for delays.

The cost of gigawatt-scale plants has more than doubled since 2004, mostly due to increases in component and material prices. And they say many investors are reluctant to sink money into larger plants because of long payback periods. One advantage of SMRs is that they can be built in blocks, and scaled up, so companies don’t have to commit everything up front.

SMRs, then, could be ideal replacements for coal-fired plants that fail to meet clear air emission standards, or for places where renewable energy production isn’t feasible.

“SMRs have the potential to achieve significant greenhouse gas emission reductions. They could provide alternative baseload power generation to facilitate the retirement of older, smaller, and less efficient coal generation plants that would, otherwise, not be good candidates for retrofitting carbon capture and storage technology,” notes the report.

The first SMR designs are currently going through the licensing and approvals process, and could start producing electricity in about 2020. Examples of SMR designs include the mPower, developed by Babcock & Wilcox and Bechtel; NuScale; and the Iris, from a consortium led by Westinghouse. (Full list here).


Babcock & Wilcox said last year that three utilities said were interested in adopting its design if it gets regulatory approval. If they get the go-ahead, the first plants are likely to be sited next to existing nuclear power stations, though some designs do not need large volumes of water to operate, and could potentially be built out in the desert, if necessary.

There are, of course, some holdups: Detailed engineering for SMR designs is only 10% to 20 % complete, cost estimates are necessarily provisional, and the government, as usual, will have to step in as a “first customer.”

And what about safety, given the current state of public opinion about nuclear power? SMRs use the same fuel and cooling technology as larger plants. But Rosner and Goldberg argue that SMR designs are safer because they use “passive safety features” rather than pump-driven systems for backup cooling. The plants are more self-contained, and designed to eliminate the need for human intervention in emergencies. That’s not enough to calm anyone down who’s worried about the next Fukushima. But if we need nuclear power, it certainly sounds like a potential safer option.

About the author

Ben Schiller is a New York staff writer for Fast Company. Previously, he edited a European management magazine and was a reporter in San Francisco, Prague, and Brussels.