Inside an airy circular building that will soon be built in a field near Oxford, England, a new machine filled with swirling liquid metal—and plasma heated to more than 100 million degrees Celsius—will begin giving visitors a close look at the potential of nuclear fusion technology.
“This is really a stepping stone to a first commercial plant,” says Christofer Mowry, CEO of General Fusion, the Jeff Bezos-backed startup that created the technology. Fusion has huge potential: It could be a low-cost, nearly limitless source of carbon-free electricity that doesn’t use much space for production, and unlike traditional nuclear plants that run on nuclear fission, it doesn’t risk meltdowns (if there’s a disturbance, the reaction stops) or create long-term radioactive waste. (At traditional plants, fission splits atoms and produces large amounts of unstable uranium, but fusion produces only helium, an inert gas, and much smaller amounts of tritium, which is radioactive, but for a much shorter time.) Scientists have been pursuing the concept for decades: The running joke is that nuclear fusion is the energy source of the future, and always will be. There’s a very real chance that it may not ever succeed. But Mowry and some others believe that it may finally be possible now.
Unsurprisingly, it’s difficult to make work, and even if it does work, it’s difficult to generate more energy than the energy needed to run the machine. Even at this new demonstration center, the company isn’t planning to generate electricity, but rather to gather the data needed to later build a commercial pilot plant that could. Many experts are skeptical that the future step will succeed. “The probability that you’re going to build a pilot plant that actually produces one milliwatt of nuclear power are very remote, I would say,” notes Edward Morse, a nuclear engineering professor at the University of California, Berkeley.
At the new demonstration plant, which will begin construction in 2022 and is scheduled to open in 2025 at the U.K. Atomic Energy Authority’s Culham Campus, the company will combine processes that it has been testing individually, and aims to “show that we can make fusion work practically at full scale in a power-plant-relevant environment, so we’ve developed and tested all the systems that are involved in this thing up to full scale,” Mowry says. “You can think about it like building an engine and a transmission and a suspension system of a car, and now finally putting those pieces together and showing you can drive it down the road.”
If fusion technology can work as its boosters hope, it could help fill a gap in the world’s transition to zero-carbon energy. Wind and solar power continue falling in cost, but it’s still expensive to store that energy so that it’s always available. Renewable power plants and batteries also take up space. Mowry argues that the compact design of the nuclear fusion technology is a better fit for dense cities. “You need something that complements both renewables and storage,” he says.
