Commercial nuclear reactors have barely changed since the first plants were commissioned halfway through the 20th century. Now, a significant fraction of the world’s 447 operable power reactors are showing their age and shortcomings, and after the Fukushima Daiichi disaster in Japan seven years ago, nuclear energy is in a precarious position. Between 2005 and 2015, the world share of nuclear in energy consumption fell from 5.73 to 4.44 percent. The abandonment of two giant reactor projects in South Carolina in the United States and the spiraling costs of completing the Hinkley Point C reactor in the United Kingdom, now projected to cost an eye-watering £20.3 billion (US $27.4 billion), have added to the malaise. Against this backdrop, several U.S. startups are pushing new reactor designs they say will address nuclear’s major shortcomings. In Cambridge, Mass., a startup called Transatomic Power is developing a reactor that runs on a liquid uranium fluoride–lithium fluoride mixture. In Denver, Gen4 Energy is designing a smaller, modular reactor that could be deployed quickly in remote sites. In this cluster of nuclear startups, TerraPower, based in Bellevue, Wash., stands out because it has deep pockets and a connection to nuclear-hungry China. Development of the reactor is being funded in part by Bill Gates, who serves as the company’s chairman. And to prove that its design is viable, TerraPower is poised to break ground on a test reactor next year in cooperation with the China National Nuclear Corp. “There are multiple levels of problems with the traveling-wave reactor,” says Arjun Makhijani, the president of the Institute for Energy and Environmental Research. “Maybe a magical new technology could come along for it, but hopefully we don’t have to rely on magic.” Makhijani says it’s hard enough to sustain a steady nuclear reaction without the additional difficulty of creating fuel inside the core, and notes that the techniques TerraPower will use to cool the core have largely failed in the past.
IEEE Spectrum 1st June 2018 read more »