r/fusion • u/Sun_In_A_Bottle • 14d ago

Why fusion, over everything else?

$15.2 billion in private investment over the past 5 years!

For an industry that is projected to need 1 million workers by 2040, how is the global private workforce roughly ONLY 4,000?!

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u/Cruisin4Fusion 13d ago

ITER is not commercially relevant and never will be so it is a moot point of comparison. That design was created in the late 80s and was never planned to be cost effective. No modern fusion device will be as large or as expensive as ITER.

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u/imtoooldforreddit 13d ago

That's actually the thing though, a commercial tokamak reactor would probably want to be even bigger. The fusion energy generation is proportional to the volume while the confinement energy is proportional to the surface area that has to maintain the magnetic confinement. So basically, the bigger, the more efficient. Iter already is pretty low on its Q factor, so getting smaller wouldn't really work.

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u/Cruisin4Fusion 13d ago

Fusion power scales with both volume and magnetic field, with a larger increase for the latter. The reason that people believed "the bigger, the more efficient" in the 80s was because of limitations to the magnet strength at that time.

CFS proved that you can achieve higher field strengths with HTS magnets so you could big smaller, more efficient machines. So, yes, getting smaller does work and any company using a magnetic confinement approach knows this.

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u/perky2012 8d ago

Indeed, this is like saying in the 80's "we want to build a giant screen for stadiums" and choosing the only technology available to them which was to build a gigantic CRT, but along came flatscreen technology making that decision redundant. The fact that ITER is a project on a generational timescale made this almost inevitable.