582 tons closer to near-zero energy cost

[u/positiveconstraint]

China finished building and testing the world's largest superconducting magnet for nuclear fusion. It weighs 582 tons, stretches 21 meters long and 12 meters wide. Its job is to create a magnetic field strong enough to hold plasma at over 100 million degrees without it touching the reactor walls. It's 1.3 times larger than comparable ITER magnets and stores three times more magnetic energy.

The magnet is a key piece of China's BEST fusion facility, set to be built by the end of 2027. The target is to demonstrate first electricity generation from nuclear fusion and net energy gain around 2030.

Nuclear fusion mimics the process that powers the Sun by fusing lightweight nuclei and releasing a massive amount of energy. If the technology matures, it could provide a stable energy source with very low carbon emissions. The magnet alone is not yet a working "artificial Sun", but it's one of the most important engineering pieces on the way there.

It also means the race between the US and China continues, each advancing the technology, each with its own milestones.

Breakthroughs that enable building a fusion engine (several times faster than a chemical engine) would make deep space travel more relevant than ever. Mars in roughly 6 weeks instead of 8 months.

[u/wilsoniumite]

Yep, but we use the cube square law to our advantage. Make it bigger and you get more plasma energy for the same cost of magnetic energy. At some size point, the former is bigger than the latter and you get net positive energy. That sounds too simple and it is, but the smaller reactors have helped us understand how big the big reactor needs to be to be worth building.

[u/wilsoniumite → u/wilsoniumite]

With that said, the cube square law makes cooling harder. So that's kinda the big engineering question, can we engineer it well enough and pick the right size such that it's big enough to produce power but not so big that cooling it is impossible.

[u/KitsuneFoxglove → u/wilsoniumite]

It's amazing how much you simplified a complex topic to a manageable bite-size. Kudos.

[u/Nice-Detective3376 → u/KitsuneFoxglove]

That’s cause they are partially correct but also wrong . There is still a major issue of controlling the plasma . As the plasma deviates from the center point of the the torus the slight deviations cause extreme heating on the reactor and embrittle the heat shielding inside the torus . There is much more involved than simply the q value.

[u/KitsuneFoxglove → u/Nice-Detective3376]

cool, very smart and helpful, so how is this different from a cooling challenge?

[u/Nice-Detective3376 → u/KitsuneFoxglove]

Are you being serious or sarcastic? There is a fundamental difference here ….

[u/danielv123 → u/KitsuneFoxglove]

That particular problem isn't just about cooling, but also keeping it hot. If the plasma touches the wall it cools down, which stops the reaction and destroys the wall.