Small-Scale Nuclear: U.S. Prospects and Global Context

Executive Summary

The U.S. nuclear power industry enjoyed 25 years of growth from its inception through early 1979. Then, an accident at the Three Mile Island nuclear plant changed everything, bringing nuclear power expansion in the U.S. to a halt for the next 45 years. 

Despite early promises of low-cost electricity, low-cost nuclear power never came to be. Plagued by high capital costs and persistent cost overrun problems through its history, the nuclear industry has struggled to compete with other sources of power. The initial response of the industry was to build ever-larger reactors, seeking benefits from economies of scale. But construction costs continued to present a problem. Now, with added competition from wind and solar, delivered electricity price competition has become even more challenging.

As a potential partial solution to safety risks, as well as high up-front capital requirements, attention has turned to small modular reactors (SMRs). One third to one fourth or less the size of typical reactors, SMRs present less danger in the case of an accident, can more easily incorporate passive safety features, and may (aspirationally at least) lower costs of nuclear energy. Thousands of reactor years of accident-free experience with nuclear powered U.S. naval vessels provide confidence that fundamental technologies are sound.

SMR development is in its early stages, with only four operational SM reactors worldwide and none in the U.S. But more than 70 designs are on the drawing board, with orders already being placed by potential early adopters.

But many hurdles remain to be cleared before SMR deployment, including technical, regulatory, political, and public acceptance challenges that include finding a solution to long-term nuclear waste disposal.

Time will tell the story, but for now the future of SMRs is uncertain.