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Topic: Our median/short-term source of energy: the Molten salt thorium nuclear reactor (Read 121 times)

legendary
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Nothing like healthy scepticism and hard evidence
Beside time, energy is our most precious commodity. All societies run on it.

If we couldn’t sustain the current energy output, we wouldn’t be able to support the present world population of about 7,4 billions (to reach about 9 billions on about 25 years).

With global warming and the possibility that oil production won’t be able to keep up with demand (Peek Oil is still a serious possibility taking in account the development of India and Africa; fracking didn’t solve this problem, could only postpone it), we are risking a serious climate and energy crisis.

Because of it intermittence and low density (no use to try to run North Europe or Canada on solar power), with current technology, renewable sources can’t really offer a complete solution to overcoming fossil sources dependency, even taking in account the major drop in prices of Solar.

After Chernobyl and Fukoshima, traditional nuclear reactors are clearly on a serious crisis (Germany decided to close all its nuclear plants by 2022).

Current nuclear plants rely on a high pressure water system in order to power an electrical generator.

Since water boils at about 100 degrees centigrade, only by submit it to a pressure as high as 70 times the normal atmospheric pressure can water temperature be increased to about 300 degrees without boiling it in order to produce energy at about 30-35% efficiency.

Well, pressuring radioactive water to 70 times the normal pressure is a dangerous business.

If the plant loses pressure, water will start boiling and vapor occupies much more space than liquid water. If the massive concrete and steel container that covers these reactors, in order to avoid any radioactive emission, is breached, one ends up with another Fukoshima.

Since the fifties there were experiments with nuclear reactors that use Molten salt as the heating/cooling instrument and not pressured water.

Molten salt reactors have a few advantages: they can reach much higher temperatures (so, they are much more efficient producing energy) and at normal pressure!

Therefore, it doesn’t need the expensive containers, so the plant is much smaller and cheaper to build.

They can be indeed very small and even be transportable! They can be manufactured on assembly lines.

Also, these reactors are much safer. They cool off on their own when temperature rises too much and the nuclear reaction can be easily stopped.


Moreover, a Molten salt reactor can be powered with thorium (that can be easily converted to uranium 233), which has some advantages over uranium:

1) Is much more common than uranium and have been mined extensively as a by-product no one currently uses. So, it's available with little mining costs.

2) Can be used almost completely (contrary to uranium, which only about 0.07% is actually consumed, leaving the rest as waste that is radioactive for thousands of years), being able to create about 200 times more energy than the same quantity of uranium.

3) Leaves relatively little waste and this waste is radioactive “only” for about 300 years.

4) This waste, contrary to the one from conventional reactors, is hard to use for weapons purposes. So, it’s much less risky to share this technology.

Finally, this new reactor can be also powered by a mix of thorium and uranium wastes created by conventional reactors.

So we can find use for this terrible legacy we are leaving to future generations.


There are a few technologic obstacles, like the corrosive nature of salt. But some projects intend to use graphite on the core to overcome it.

Nobody will stop this now: the Chinese, the Indians, the USA, Canada and also a few European countries are racing to build a fully working reactor of this kind.

https://www.youtube.com/watch?v=bbyr7jZOllI

https://www.youtube.com/watch?v=Kv_XjHPJjEg


https://en.wikipedia.org/wiki/Molten_salt_reactor#Twenty-first_century

https://www.extremetech.com/extreme/254692-new-molten-salt-thorium-reactor-first-time-decades

http://www.businessinsider.com/thorium-molten-salt-reactors-sorensen-lftr-2017-2

It seems our future is nuclear: first, Molten salt thorium fission; then, fusion.
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