I am confused as to how power in a fusion reactor is extracted from the plasma. I understand that the kinetic energy of the particles such as neutrons emitted from the reactor can be decelerated, but can anyone go into a bit more detail about the nature of the walls in the tokamaks, and how energy is extracted, since I think it definitely isn't through conventional methods where a turbine is turned.

If I'm understanding this correctly, it does actually work by the traditional heat-a-fluid-turn-a-turbine method. The fluid appears to be liquid lithium in the case linked above - presumably that has a high cross-section for neutrons of the energy emitted by the fusion reactions.

It's just another damn silly way to boil a kettle¹ (full of Lithium), as I understand it.

¹ Does anybody know who I'm (mis?)quoting here? Can't find it on Google...

Oh, I didn't know that. Thank you. I am interested however, to know how the kinetic energy of the neutrons is used to heat the liquid. does it have to do with converting the kinetic energy of the neutrons? I read something about the energy being received by decelerating energetic particles in an electric field, but I can't find anything about how that might work. It involves the kinetic energy of the neutrons and has something to do with magnetohydrodynamics, but that's all I know so far. Can you provide any insight? If you have any papers about the ITER project, that would be welcome too.

Thanks in advance

Direct conversion to electricity has been demonstrated from radioisotopes. It has a bad efficiency, better only than thermoelectric converters. Wherever a static converter isn't needed, conversion is made through thermal engines - understand: a turbine and alternator.

Magnetohydrodynamics works only in inventor's wishes and people's science up to now. When you put figures on its efficiency, it's ugly. Until someone comes with better ideas.

Neutrons heat materials (like liquid lead-lithium eutectic) as they lose speed there. Once you get heat, the rest is well-known.

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Neutron absorption and heat removal are essentially the same in a Tokamak because neutrons receive most of the fusion energy. These functions are completely linked with tritium regeneration (search keywords) because both need to catch all neutrons.

Alas, tritium regeneration needs to multiply the neutrons, and the only promising method uses lead spallation, which creates huge amounts of radioactivity. As much radioactivity as a uranium reactor of identical power, see my estimates there:
http://saposjoint.net/Forum/viewtopic.php?f=66&t=2450#p32310

What a disappointment. And what a deception by people working on tokamaks. Knowing that, I prefer to abandon tokamaks completely and concentrate on other sources.

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The wall material is still an open question. People will certainly find materials (steel, graphite) that operate for some time. The material could even survive long enough that it gets replaced at the normal maintenance stops of the plant - if research succeeds. But specialists have admitted that this material will become hugely radioactive; their only (questionable) hope would be to restrict radioactivity from the walls to a few centuries.