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?!

39 Upvotes

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-4

u/x7_omega 14d ago

Some factors, perhaps not the strongest:

  1. Ignorant hope of "clean nuclear", even though even p-B11 is not aneutronic. At 1GW power, 0.2% in neutrons is quite an envy of a neutron source to have around.
  2. Ignorant hope of "cheap nuclear", even though the basis for a feasibility study does not exist yet.
  3. Ignorant rejection of fission as "dirty", though not baseless outside Russia with their fast reactors and soon to be closed nuclear cycle, but this factor kills the vibe. And your typical nuclear bro is the vibe variety of investor.

The question I would like to see asked to the nuclear bros community: why no one, not a single soul, even mentions pure He3 fusion? The only relevant completely aneutronic fusion reaction, and easier than p-B11.

5

u/perky2012 14d ago

Because pure He3-He3 requires very high temperatures, has a very low reaction rate and suffers from bremsstrahlung losses .

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u/x7_omega 13d ago

Still easier than p-B11, for which there are 3 projects (TAE, Marvel and HB11).

3

u/Chrontius 13d ago

There's also #4: Using fusion neutrons to burn stuff that the fission chain reaction swears is burned to hellandgone, in order to extract the last 97% of the remaining energy from your lanthanides and shit.

This is my favorite plan, because it reduces the amount of high level waste we have to worry about in the long term, and we already have fuel for centuries stockpiled.

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u/x7_omega 13d ago

Cheap (or free) fusion neutrons as a commercial product for transmutation as an industry is the most interesting business case for fusion now. A notional D-D reactor with enough power output for its own systems, plus for deuterium production, is essentially a free neutrons machine operating barely above energy breakeven. Transmutation pays for ammortisation and operating costs, hence machine becomes more profitable the longer it operates.
Not only waste burn, there are many other uses with a clear business case. This is alike to "minimum fusion" concept by Helion, and they are the closest now to implementing this.

1

u/Chrontius 13d ago

Like, I'm not just here to burn down the waste, I want those fucking exajoules locked away in the scary trash!

2

u/Legitimate_Humsn 13d ago

Fast fission reactors are much more practical for burning spent fuel, but we're not even doing that so

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u/Sad_Dimension423 14d ago

It's not easier than p-B11.

0

u/x7_omega 13d ago

Oh, really? A machine that does not have to be designed to survive megawatts in neutron flux for years, while operating reliably enough to make money, is not easier than a machine that does the same in neutron flux? Paper reactor designs have always been easier, but it is a different industry.

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u/Sad_Dimension423 13d ago

Yes, really. Simply getting 3He to react sufficiently is harder than getting p-B11 to react. It's probably impossible in any practical way. That it would have fewer neutrons is irrelevant if you can never get to that.