The following submission statement was provided by /u/filosoful:

A clean, plentiful fuel so efficient Earth's entire annual supply could fit in a swimming pool. That's the dream, but the science is there, too

The hottest place in our solar system is not the Sun, as you might think, but a machine near a south Oxfordshire village called Culham. Housed inside a vast hangar, it’s a nuclear fusion experiment called JET, or Joint European Torus.

When operating, temperatures here can reach 150 million degrees Celsius – ten times hotter than the centre of the Sun. On December 21st 2021, JET set a new record by producing 59 megajoules of sustained energy through a process known as nuclear fusion.

59 megajoules isn’t a huge amount; just enough to power three domestic tumble dryer cycles. Nevertheless, as far as humanity is concerned, proof that nuclear fusion works is a very big deal indeed.

Fusion produces energy by fusing atomic nuclei together, the opposite of what happens in all nuclear power stations, where atomic nuclei are split through nuclear fission.

Once harnessed on a commercial scale, fusion could produce so much energy from so little raw material, that it may solve all of humanity’s energy problems in one fell swoop – amongst many other things.

Please reply to OP's comment here: https://old.reddit.com/r/Futurology/comments/xwhq37/many_scientists_see_fusion_as_the_future_of/ir6h2io/