HOT FUSION: THE DREAM—AND THE HYPE—LIVE ON

Scientists working to create fusion reactors that would produce limitless clean energy by melting hydrogen atoms together announced what they called a “breakthrough” earlier this month: the Joint European Torus (JET) fusion reactor in the U.K. set a new record for the amount of energy produced—59 megajoules, shattering the 1997 record of 21.7.
Exactly how much is that?
A joule is roughly the amount of energy it takes to raise an apple three feet, or one meter, off the ground. A megajoule is a million joules. So the fusion reactor put out enough energy to raise 59 million apples three feet off the ground all at once.
The reactor put out that much energy for five seconds.  Then it hit a wall.
Producing fusion power begins by creating a hydrogen plasma—a high-energy state of matter in which atoms are stripped of their electrons. The plasma is suspended in the center of a sealed chamber. The plasma is held in place by electromagnets that are among the world’s most powerful.
Microwaves, lasers, or other intense forms of energy then heat the plasma to at least six times hotter than the surface of the Sun. The heat, and the pressure from the magnets, exert enough force on the hydrogen atoms to fuse them, releasing vast amounts of power that can be harnessed.
The reason the JET’s record heat level lasted only five seconds was that if it had lasted longer, its magnets would have melted.
Also, even though 59 megajoules was a record high temperature to make in a fusion reactor, it still was less energy than it took to run the reaction itself.
JET engineers are developing the next generation of cooling systems to keep the magnets from melting.
Undeterred and always hopeful, the U.K.’s nuclear power agency has chosen five candidate sites in Britain for the kingdom’s first commercial fusion reactor and has held community meetings in those areas to sell the project’s benefits to locals.
TRENDPOST: After a half-century of research and hundreds of billions in public and private money invested, hot fusion has yet to show any sign that it can become a practical source of commercial power.
However, scientific careers have been built and reputations made doing the work.
With so much sunk cost invested, the field will not be allowed to die.
Still, the conventional approach has proven impractical.
Hot fusion’s future will depend on entirely new technologies, such as HB11 Energy’s boron-centered process now in development that we reported on in “New Fusion Energy Method Revives Advocates’ Hopes” (2 Mar 2021).
Meanwhile, grid-scale battery storage and decentralized power mini-grid technologies continue to advance and the price of renewable energy continues to fall while efficiencies rise.
A commercial hot fusion power plant is unlikely to appear within the next ten years. By then, it might not be able to justify the billions of dollars it will cost to build.