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by mrarjen 2339 days ago
Personally I'm all for having mini reactors if it means we can generate reliable energy with minimal pollution. Anything that helps reduce emissions should be considered.

But this would need to be a fail save type of reactor and with a clear plan(s) all the way down to how the waste is handled till it's no longer active.

3 comments

TerraPower [1] seem to have a good alternative with its Traveling Wave Reactor. It can be run on nuclear waste we already have and provide energy to 10bln people with US per capita power consumption for basically eternity.

[1] https://en.wikipedia.org/wiki/TerraPower

Always be wary of grandiose claims like this that amount as much to facts as to marketing material.
These are well-known properties of any fast reactor, like Terrapower's.

Only about one percent of high-level nuclear waste is fission products, the broken-apart atoms left after fission. The rest is U238, unused U235, plutonium, and other transuranics produced by absorbing neutrons without fissioning. Fast reactors can fission all of these. That's why they can run on nuclear waste.

For the same reason, they can get over a hundred times as much energy from the same amount of uranium ore. Conventional reactors can only use the U235, which is 0.7% of natural uranium.

That's a great start, but with such efficient use, it's practical to get the uranium from seawater. We can do that now at five times the cost of mining; if we only need 1% as much uranium, then total fuel cost would be 5% as much as nuclear reactors spend on fuel today. Fast reactors fueled from seawater would last for millions of years.

Breeders and seawater would likely last even longer than that, as U in seawater is in a pseudo-equilibrium, constantly leaching from bedrock.
If it wasn‘t for Bill Gates I‘d be much more sceptical about it, but he‘s a huge advertiser which gives hope.
From your Wikipedia link:

TLDR: Its all just theoretical.

"TerraPower planned to build a 600 MWe demonstration Plant, the TWR-P, by 2018–2022 followed by larger commercial plants of 1150 MWe in the late 2020s.[15] However, in January 2019 it was announced that the project had been abandoned due to technology transfer limitations placed by the Trump administration."

I'd much rather nuclear production operations be handled by larger plants, and storage be handled by the customer. Storage efficiency is the current weak point, not production efficiency.
I'm for them if they make economic sense and also can't go critical, as in you can more or less hit a switch and they go dead and criticality isn't a possibility. There have supposedly been designs that guarantee that, but I saw nothing in the article about it.