Progress in fusion research can seem contradictory at times. Take Tri Alpha Energy, for example, a company founded by physicist Norman Rostoker that’s working to develop fusion power. For the last 17 years, the company’s scientists and engineers have been feverishly working to contain stable, superheated plasma. A couple of weeks ago, the secretive company succeeded. Their moment of triumph lasted just five milliseconds.
That’s an order of magnitude longer than researchers had previously been able to achieve using a field-reversed configuration, which is way of confining the plasma by using its own flow to create a magnetic field.
FRC is a different approach than what’s used in other fusion experiments like ITER, which employs supercooled magnets to create the confinement field. (The Tri Alpha experiment wasn’t entirely magnet-free. To get the plasma hot enough in the first place, they needed to fence it in using—yes—magnets.)
Tri Alpha already has plans to tackle the next challenge. Here’s Daniel Clery, reporting for Science:
[Chief technology officer Michl] Binderbauer says that next year they will tear up C-2U again and build an almost entirely new machine, bigger and with even more powerful beams, dubbed C-2W. The aim is to achieve longer FRCs and, more crucially, higher temperature. A 10-fold increase in temperature would bring them into the realm of sparking reactions in conventional fusion fuel, a mixture of the hydrogen isotopes deuterium and tritium, known as D-T. But that is not their goal; instead, they’re working toward the much higher bar of hydrogen-boron fusion, which will require ion temperatures above 3 billion degrees Celsius.
The reason for the stretch? Boron is abundant here on Earth, tritium isn’t. Plus, hydrogen-boron fusion produces much less radiation, meaning the reactor itself won’t become a radioactive mess as quickly as with D-T fusion.
Still, even if Tri Alpha creates stable plasma at 3 billion degrees C, they still have a long road ahead. Five milliseconds, while impressive, isn’t nearly long enough to power a commercial plant.
Photo credit: NASA Goddard