A new breed of nuclear reactor designed by engineers from the millennial generation has gained the support of both billionaires and the United Nations agency overseeing the industry.

The International Atomic Energy Agency is opening an exchange for countries to trade information on a technology that uses molten salt to moderate the atomic reaction of liquid fuels, rather than water and solid fuel. The exchange offers backing to investors ranging from Bill Gates to Peter Thiel, who have supported the new-model reactors as both safer and cheaper.

The Plant Vogtle nuclear facility in Waynesboro, Georgia. The US is accelerating the retirement of its aging fleet of nuclear plants. Credit:Mary Ann Chastain

The push comes as the US accelerates retirement of its aging fleet of nuclear plants, and utilities tilt toward cheaper natural gas and renewables. Eighteen US reactors are now being decommissioned, and a half-dozen more face closure for economic reasons. A wave of retirements around 2030 will further diminish the nation's biggest source of low-emissions power, threatening the fight against global warming.

"The technology used in today's reactors is never going to be economical," said Rory O'Sullivan, the 30-year-old chief operating officer at Moltex Energy in London. The new molten salt design "has the potential to disrupt the entire energy system," he said.