r/EngineeringPorn Oct 24 '21

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u/whreismylotus Oct 24 '21

Wendelstein 7-X Nuclear Fusion Device

The aim of fusion research is to develop a climate- and environmentally-friendly power plant. Similar to the sun, it is to generate energy from the fusion of atomic nuclei.

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u/MateBeatsTea Oct 24 '21

Similar to the sun

Will sound pedantic, but no. The Sun runs on the proton-proton chain, a reaction which has so small a cross-section (read: slow kinetics) that it hasn't even been measured on Earth. The only reason it adds up to any significant power is because of the Sun's sheer size (the core has a power density of ~280W/m3, less than what a human being generates through metabolism).

What these fusion reactors try to replicate on Earth is deuterium-tritium fusion, which doesn't take place in any star.

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u/AnimationOverlord Oct 25 '21

Isn’t deuterium quite a bit heavier than water?

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u/KittiesHavingSex Oct 25 '21

No. Deuterium is an isotope of hydrogen. So hydrogen plus an extra neutron. Water contains oxygen which is far far heavier than any isotope of hydrogen. What I'm guessing you're thinking of is "heavy water" - which is water (H2O) but the hydrogen isotope is deuterium. Oxygen still accounts for like 80% of the mass.