How does nuclear fusion solve the issue of rivers getting too hot, such that the plant has to shut down?

There are fusion reactor designs that don't use water. They directly convert to electricity with magnetic fields.

Are you sure about this ? Not heat is produced ? Cold fusion has been controversial in the 80's (https://en.wikipedia.org/wiki/Cold_fusion) and never really escape the lab.

They're likely referring to p+B11 fusion which is a potentially viable reaction that emits all its energy as accelerated charged particles (a current), which can, in theory, be slowed down by inducing a current in a coil (direct conversion). This skips the thermal cycle of electricity generation. There would still be heat, but it would be contained to the plasma with some amount of leak/waste.

There are a great number of asterisks on this. We are not close to making a p+B11 reactor.

Interesting. But I suspect it would take quite some time to get something like that in production. Nonetheless, we should keep do research, it could be the next generation of fusion reactors.

It depends on how bullish you are on Zap and Helion.

I think it is exciting times, but there are inevitable booms and busts in hype and funding. Results are what matter, and those are coming.

Helion is one of them. Supposedly their 8th prototype called Polaris will be able to demonstrate the production of a small amount of net electricity by 2024. We will see what happens.

https://www.helionenergy.com

https://en.wikipedia.org/wiki/Helion_Energy

https://news.ycombinator.com/item?id=29119180

That isn't much of an issue unless the river is extremely small. The huge amount of water traveling on most rivers with nuclear plants is orders of magnitude more than what's used in to do the heat transfer in the reactor.

It’d be great but … when does it go online? I’m not going any more and it’s been “real soon now” for my entire life. We no longer have decades to wait, especially when we can cover the vast majority of needs with renewables for less money.