To count as a fusion power plant, the majority of the energy has to be derived from fusion and it has to output more power than it takes in. If most of the fusion energy comes from D-T fusion, but some other reactions also take place, that counts as D-T.
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@JonathanRay Curious why you are so bearish on any fusion power plant existing at all. I would put it at >80% that it will be possible to make a plant with net end-to-end energy gain, and >80% that if it's possible by then, then a power plant would exist (which would imply >64% of a plant existing, and <36% of no plant existing).
@BoltonBailey It's probably impossible to reach real breakeven with any small reactor, except maybe with D-T, and the neutron flux from D-T would destroy your equipment in a day.
@JonathanRay Why are do you say small reactors though? I certainly expect breakeven to first be reached with a large reactor.
By small I mean the plasma doesn’t have enough optical thickness to substantially boost the Q factor in an MCF device. Any reactor likely to be built is small by this definition.
Inevitable neutron flux from side reactions (for any fuel except P-B) will rapidly destroy any mirrors and electronic equipment in the vicinity. This makes MCF seem commercially doomed even if they could break even in a brief test (but nobody even came close yet. The best I can find was JET with Q=0.67 in 1997, but the denominator there is power delivered to the plasma, not wall-plug power, and the numerator is thermal from fusion, not electricity generated, so you would need to improve that result by a lot)
@JonathanRay On second thought even with P-B the high energy alpha particles hitting B probably generate some neutrons.
D-T icf at least has a sort of proof of concept in the form of thermonuclear weapons. It’s just a question of whether they can miniaturize it by a factor of 10^9 and replace the fission primary (that powers x-Ray implosion in the teller-ulam design) with burst lasers without killing the efficiency.
Magnetic confinement is probably a lost cause because radiative losses will probably far exceeed the rate of fusion at any combination of temperature and density for D-T, and any other fuel would be orders of magnitude worse in that respect.
Buying low prob outcomes, I don’t think we have much evidence now.
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