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Comment by taf2 | Hacker News Reader

" plant will use this heat to produce steam and then electricity by way of turbines and generators"

Has anyone thought of a better way to "harness" power to produce electricity than heat? I'm guessing in the future there will be a more efficient way that changes how we think about the production of electricity.

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If we manage aneutronic fusion, the output will primarily be fast-moving charged particles, which could be converted to electricity without a heat cycle. Helion, Tri Alpha, and LPP are all attempting aneutronic fusion reactors that would work this way.

The ugly truth is that the means of capturing the power really isn't the major hurdle to ITER. If you can get better than breakeven fusion in a containment vessel that won't be broken down by sputtering from fast neutrons, with the densities and temperatures you need for longer than a microsecond or two, all while breeding your own tritium, that would be the miracle. Unfortunately ITER has not come close to that, and really no one else has either .

The efficiency of modern steam turbines is not too bad. And considering that a lot of energy is used for water heating anyway, the overall efficiency (term: co-generation) is even higher.

Importantly, according to this

https://physics.stackexchange.com/a/191465/7911

the efficiency of steam is not far from the thermodynamical maximum under the assumption that the nuclear energy is initially converted into thermal heat in solid objects. You can do better, but only by harnessing the fission products (neutrons, protons, etc.) themselves before they thermalizes with surrounding material. This is possible, but it's a completely new and separate challenge in nuclear engineering, with a maximum improvement of about a factor of 2 in energy efficiency.

https://modernelectron.com/ maybe?

The one who invents a heat-to-electricity converter with suitable efficiency will be the winner of XXIst century. In nuclear installations, we're around 33% efficiency (plus, notably, half this electricity is produced during night). I read about Seebeck generators (heat-to-electricity with no moving parts), but they're even less efficient, and all those generators require a source of cold and warm it up. https://en.m.wikipedia.org/wiki/Thermoelectric_generator

A turbine can extract energy from the expansion of any hot gas. I suppose steam is common because of how easy it is to access liquid water and concentrate it around your heat source.

Wind, solar, hydro

The fun thing there is that other than photovoltaics, maybe (I don't personally understand them well enough to say for sure), the other two alternatives you are mentioning are also "nuclear -> heat -> mechanical force -> electricity" chains :)

Is just that some of the infrastructure is pre-existing.

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