Originally Posted by Mand12
It's even worse than that.
Fifteen years ago I saw a demonstration of fuel that can't melt down. Literally can't. As temperature increases, the fuel pellets themselves absorb more neutrons and moderate the reaction. It self-stabilizes below the melting point, so even if you lose all cooling, the fuel itself is still safe. To demonstrate this they had some of the control rods on pneumatic pistons that could eject them from the core very quickly. When doing that, the reaction spikes, and peeking down from the top of the pool the reactor sits in I saw the bright blue flash of Cherenkov radiation from the spike in reaction rate, which over a couple seconds damped back down to normal. They didn't adjust anything else about the reactor, just removed some of the control rods and the reaction restabilized on its own.
They've had this for decades, but no one hears about it, and any time a new plant wants to get put in people don't want it. The problem is that people are assuming plants with 1970s technology are all we could possibly do, yet don't stop to think that maybe the same sorts of technological improvement we've seen in oh, I don't know, computers, might also have happened in nuclear engineering. Nah, they're all unreliable deathbombs waiting to go off.
Fusion won't have any of these problems, but it'll still be a hard sell because OMGNUKEYOOLAR