Scientists in Germany today switched on a new kind of nuclear reactor, the latest experiment in the quest to produce clean, sustainable power from controlled nuclear fusion.
Chancellor Angela Merkel flipped the switch on the Wendelstein 7-X, a $435 million, doughnut-shaped apparatus built at the Max Planck Institute for Particle Physics in Greifswald. Hydrogen was injected into the device, superheated by microwaves until it became type of matter known as plasma for a fraction of a second.
Smashing hydrogen nuclei together releases huge amounts of heat—this is how the sun works—and not much radioactive byproduct. But despite decades of research, nobody has yet produced more energy from fusion reaction experiments than the energy put in.
Still, interest in fusion power is growing worldwide. A number of commercial and research efforts have made recent incremental achievements. And new corporate players have come into the mix, including an effort by Lockheed Martin.
Most efforts try to contain hot plasma within strong electric currents, using a doughnut-shaped device called a tokamak. The world’s largest tokamak is under construction in France at an international facility known as ITER that might cost $50 billion when completed.
Commercial players are exploring all kinds of exotic setups. Tri-Alpha, a company based near Irvine, California, is testing a linear-shaped reactor. Helion Energy of Redmond, Washington, is trying to use a combination of compression and magnetic confinement, while General Fusion, based in Vancouver, British Columbia, tries to control plasma using pistons to compress molten lead and lithium. The mixture also acts as a coolant that can be circulated to generate electricity through conventional steam generators and turbines.
These efforts are all many years away from providing meaningful amounts of electricity, as is the reactor that was tested today in Greifswald. Its design is something different again. Though similar in shape to a tokamak, it uses a complex system of magnetic currents to do the confinement. It is known, fittingly, as a stellarator.
Toronto wants to kill the smart city forever
The city wants to get right what Sidewalk Labs got so wrong.
Saudi Arabia plans to spend $1 billion a year discovering treatments to slow aging
The oil kingdom fears that its population is aging at an accelerated rate and hopes to test drugs to reverse the problem. First up might be the diabetes drug metformin.
Yann LeCun has a bold new vision for the future of AI
One of the godfathers of deep learning pulls together old ideas to sketch out a fresh path for AI, but raises as many questions as he answers.
The dark secret behind those cute AI-generated animal images
Google Brain has revealed its own image-making AI, called Imagen. But don't expect to see anything that isn't wholesome.
Get the latest updates from
MIT Technology Review
Discover special offers, top stories, upcoming events, and more.