The tokamak is the only serious path to fusion; the stellarator is a scientific curiosity
The core idea stands, but key numbers or details have changed.
TaughtMagnetic-confinement fusion means the tokamak, the doughnut design that holds every record. The stellarator, with its baroque twisted magnets, is an elegant idea that never kept up. It is a research sideline, not a contender.
NowOn 22 May 2025 the Wendelstein 7-X stellarator held the fusion 'triple product' (the combination of density, temperature and confinement time that gauges how close you are to a power plant) at a record level for 43 seconds, outperforming what any tokamak had sustained for that long.
What actually happened
The triple product is the honest scorecard of fusion, and for its whole history the highest values belonged to tokamaks like JET and JT-60U. The catch is that they hit those peaks in brief bursts. A power plant needs the performance held steady, and that steady operation is exactly what the stellarator's twisted geometry is built for. Feeding the plasma with a pellet injector from Oak Ridge, Wendelstein 7-X sustained record-level performance for 43 seconds, a regime tokamaks had not reached for that duration.
The fair hedge: tokamaks still own the highest instantaneous peaks, and neither design is anywhere near returning net power to a grid. So this is 'updated,' not a coronation. But the confident framing that the stellarator was a museum piece while the tokamak was the only real horse in the race stopped being true. There are now two serious designs, and the underdog just set the record that matters most for a working reactor.
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Who was taught this
Still standard through 2025, so anyone who finished school between 1950 and 2025 learned the earlier version.