The US National Ignition Facility has achieved even higher energy yields since breaking even for the first time in 2022, but a practical fusion reactor is still a long way off
Technically fission has a similar physical barrier to infinite meltdown. Once the water leaves the core, the reaction stops. It was called China Syndrome, and we wouldn’t have worried about it at all, had the physicist that thought it up been a bit more competent with his math skills. Unfortunately, there are plenty of other ways that the reactors that we currently use can catastrophically fail.
Technically fission has a similar physical barrier to infinite meltdown. Once the water leaves the core, the reaction stops. It was called China Syndrome, and we wouldn’t have worried about it at all, had the physicist that thought it up been a bit more competent with his math skills. Unfortunately, there are plenty of other ways that the reactors that we currently use can catastrophically fail.