/ 9 December 2016

Safer, smaller, salty nuke reactors on the cards

Caution over the prohibitively expensive nuclear project cost two finance ministers their jobs.
Caution over the prohibitively expensive nuclear project cost two finance ministers their jobs.

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

The International Atomic Energy Agency (IAEA) 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 such as business magnate Bill Gates and venture capitalist and activist Peter Thiel, who have supported the new-model reactors as safer and cheaper.

The push comes as the United States accelerates the retirement of its ageing fleet of nuclear plants, and utilities shift to cheaper natural gas and renewable energy. Eighteen US reactors are 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 chief operating officer of Moltex Energy in London. The new molten salt design “has the potential to disrupt the entire energy system”, he said.

O’Sullivan said he expects to see utilities shifting towards more use of wind and solar, bolstered by smaller on-demand nuclear plants.

Unlike most existing reactors, which use water to moderate nuclear reactions inside massive containment vessels, molten salt reactors, or MSRs, operate under normal atmospheric pressure. That’s important in the event of an accident, because pressure wouldn’t build up to the point of explosions such as those witnessed at Chernobyl and Fukushima.

“They have some very interesting safety features,” said Stefano Monti, the IAEA’s head of nuclear power technology development.

The agency’s exchange may help engineers to standardise molten salt designs and aid “near-term deployment”, he said.

Also, by eliminating the need for the costly containment vessels built around pressurised water reactors, MSR proponents say their units can be built with less investment and deployed in smaller and more modular configurations.

“We need a new nuclear paradigm,” said Nebojsa Nakicenovic, a climate scientist at the International Institute for Applied Systems Analysis. “If nuclear is to play a role averting climate change, we need more modular units that are smaller.”

Leslie Dewan is the founder and chief executive officer of Transatomic Power, a Cambridge, Massachusetts-based molten salt reactor designer backed by Thiel’s Founders Fund. She presented her design to the IAEA in September and is working with the US energy department to build a prototype in Idaho.

“I have always been an environmentalist, and I think nuclear power is one of the most important ways to produce more carbon-free electricity,” said Dewan, who envisions atomic power costing less than coal.

“Things are accelerating rapidly,” she said. “There’s growing urgency around climate change and the recognition that we have to use everything at our disposal to generate better forms of carbon-free electricity.”

Thiel, who built his fortune by founding the online payment system Paypal and was an early backer of Elon Musk, was one of US president-elect Donald Trump’s strongest supporters in the election campaign.

Trump has said nuclear technologies should play a bigger role in the US, and Congress is working on legislation backed by both main parties that lawmakers in Washington may be ready to clear early in the next administration.

That would accelerate advanced nuclear technologies.

Sceptics are already girding themselves for the likelihood that “legislation in some form will be enacted”, said Edwin Lyman from the Union of Concerned Scientists in Washington. “Molten salt reactors will present many novel safety and security issues for regulators that will require significant time and resources to resolve.”

Meanwhile, start-ups such as Transatomic could play a key role by kick-starting the stagnant US nuclear industry. That would allow the US to catch up with the next generation of Chinese and Russian nuclear designs already being connected to the power grid, according to Ken Luongo, a former director of the US energy department.

“There is a lot at stake for the US, its allies, and global stability and economic growth,” said Luongo, who helps to lead the Global Nexus Initiative, which unites nuclear proponents and environmentalists. “The nexus of nuclear, climate and global security is a critical intersection.” — Bloomberg