A Nuclear Startup Will Fold After Failing To Deliver Reactors That Run on Spent Fuel (technologyreview.com)
Transatomic Power, an MIT spinout that drew wide attention and millions in funding, is shutting down almost two years after the firm backtracked on bold claims for its design of a molten-salt reactor. From a report: The company, founded in 2011, plans to announce later today that it's winding down. Transatomic had claimed its technology could generate electricity 75 times more efficiently than conventional light-water reactors, and run on their spent nuclear fuel. But in a white paper published in late 2016, it backed off the latter claim entirely and revised the 75 times figure to "more than twice," a development first reported by MIT Technology Review. Those downgrades forced the company to redesign its system. That delayed plans to develop a demonstration reactor, pushing the company behind rival upstarts like TerraPower and Terrestrial Energy, says Leslie Dewan, the company's cofounder and chief executive. The longer timeline and reduced performance advantage made it harder to raise the necessary additional funding, which was around $15 million. "We weren't able to scale up the company rapidly enough to build a reactor in a reasonable time frame," Dewan says.
But I thought there were already "breeder reactors" that did this. How was this design different from them?
Old fashioned breeder reactors turn U-238 into plutonium. Although plutonium can be used as reactor fuel, it can also be used to make bombs. Furthermore, these reactors use fuel rods, and pressurized containers, and have the same complexity and safety problems as LWRs.
What makes this reactor different is that it doesn't make plutonium, it burns the fuel that in breeds in situ so no extra expensive reprocessing is needed, and it is an inherently safe design: It can't have a "meltdown" since it is already liquid, and it is not pressurized.
That is the theory. In practice, molten salt reactors don't have a very good track record.
Molten salt reactor