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What is a molten salt reactor?

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Re: What is a molten salt reactor?

#21

Post by credit_guy »

ncmncm wrote: post #5

A molten salt reactor is, first and foremost, a distraction . By the time any production molten-salt reactor design could get proved out and the first commercial one built, renewables + storage will be providing all our power for much less money than it ever could. But we can waste a lot of $billions on it that could instead go to build out a hell of a lot of panels and wind turbines.

History does not end in 20 years though. Humanity will continue to exist for hundreds, thousands of years, probably more.

I agree with you that we don't need nuclear power to solve the climate change problem. But once we are done with that, we will continue to live. Research in new types of nuclear power will yield benefits, even if on a timeline that is beyond the target date for net zero emissions (2050 or so).

Re: What is a molten salt reactor?

#22

Post by inglor_cz »

ncmncm wrote: post #5

A molten salt reactor is, first and foremost, a distraction . By the time any production molten-salt reactor design could get proved out and the first commercial one built, renewables + storage will be providing all our power for much less money than it ever could. But we can waste a lot of $billions on it that could instead go to build out a hell of a lot of panels and wind turbines.

I am personally not willing to put all the eggs into one basket, because I don't share your certainty about future course of things.

We have some lessons from the Energiewende in Germany, which turned out much more expensive than promised. German Green minister Jürgen Trittin assured the German public in 2004 that support for renewable energies is going to cost them "one ice cream scoop per month" [0]. Which was so wildly off-mark that you can only laugh about it bitterly in 2022.

Now it is possible that molten salt reactors are a waste of money, but I would still prefer having more options open for the future. Especially your idea that storage will be cheap needs to be tested in reality first. Currently, storing of electric energy is darn expensive.

[0] https://de.wikiquote.org/wiki/J%C3%BCrgen_Trittin

Edit: instant downvote instead of counterarguments. Energy storage is still pretty expensive regardless of the # of votes (positive or negative) that this comment attracts.

Re: What is a molten salt reactor?

#23

Post by pydry »

omega3 wrote: post #13
ncmncm wrote: post #5

A molten salt reactor is, first and foremost, a distraction . By the time any production molten-salt reactor design could get proved out and the first commercial one built, renewables + storage will be providing all our power for much less money than it ever could. But we can waste a lot of $billions on it that could instead go to build out a hell of a lot of panels and wind turbines.

There are countries where neither solar nor wind are a viable options.

Where?

Re: What is a molten salt reactor?

#24

Post by ncmncm »

cmurf wrote: post #20
ncmncm wrote: post #18

Earlier quoted context omitted.

There are not enough of them to be a big problem. Numbers matter. They are importing fuel now , and may continue. In the future the fuel they import will be cheaper if synthetic. Or they may rely more on transmission lines, and stockpile synthetic fuel for backup in case of outages. People everywhere will do what works best for them where they are. As synthetic fuel cost drops below extracted and refined hydrocarbons…

What's an example of a synthetic fuel suitable for this purpose? I wouldn't call methane synthetic, for example.

Anhydrous ammonia stores liquid at room temperature under light pressure, stores energy per unit volume close to hydrocarbons, and can be burned where they can.

But in the near future, synthetic methane will be cheaper than mined natural gas. More expensive than ammonia, necessarily, because it needs carbon.

Re: What is a molten salt reactor?

#25

Post by abracadaniel »

m0llusk wrote: post #19

This boldly claims that molten salt reactors are safe, but my understanding is that these systems require carefully engineered coatings to function and that in practice every such system has leaked liquid sodium. The statement may be essentially true kind of like saying elevators are safe, but there is still room for risk analysis and expectation of occasional failures.

Storing and piping molten salt proved too unreliable for the Crescent Dunes solar collector. Swapping out the simple and free heat source with a much more complex nuclear reactor doesn’t seem like a good idea.

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

Re: What is a molten salt reactor?

#26

Post by ncmncm »

credit_guy wrote: post #21
ncmncm wrote: post #5

A molten salt reactor is, first and foremost, a distraction . By the time any production molten-salt reactor design could get proved out and the first commercial one built, renewables + storage will be providing all our power for much less money than it ever could. But we can waste a lot of $billions on it that could instead go to build out a hell of a lot of panels and wind turbines.

History does not end in 20 years though. Humanity will continue to exist for hundreds, thousands of years, probably more. I agree with you that we don't need nuclear power to solve the climate change problem. But once we are done with that, we will continue to live. Research in new types of nuclear power will yield benefits, even if on a timeline that is beyond the target date for net zero emissions (2050 or so).

There is long-term value in nukes for operations in the outer solar system, but design criteria for operation there are very different. No need for containment; minimal, directional shielding if any; 100% automated operation.

pB11 fusion, ultimately.

Re: What is a molten salt reactor?

#27

Post by ncmncm »

pydry wrote: post #23
omega3 wrote: post #13

Earlier quoted context omitted.

There are countries where neither solar nor wind are a viable options.

Where?

Usually Finland is mentioned. Norway has hydro, anyway. Archangelsk, Kamchatka, Siberia, Fairbanks. McMurdo Station. There are places.

They seem to do OK importing liquid fuel. Dunno why they would have to stop.

Re: What is a molten salt reactor?

#28

Post by Manuel_D »

ncmncm wrote: post #5

A molten salt reactor is, first and foremost, a distraction . By the time any production molten-salt reactor design could get proved out and the first commercial one built, renewables + storage will be providing all our power for much less money than it ever could. But we can waste a lot of $billions on it that could instead go to build out a hell of a lot of panels and wind turbines.

Some energy markets are already hitting saturation periods for renewables. This creates diminishing returns, where more and more of the energy generated from an intermittent source isn't actually used. We were promised that storage would be made cheap enough to capture this excess energy and release it during hours of under-production. But so far nothing has delivered storage at competitive costs.

Furthermore, renewable generation varies a lot by region. Solar's cost per watt is way different in California or Hawaii than it is in Massachusetts. This is both in terms of less sunlight (inclination of the Earth, plus weather) but also land costs. This could be ameliorated by long-distance transmission, but that has its own problems even within small states [1]. And we'd have to increase the net-cost of deployments to match.

There's none of these asterisks and hand-waving with nuclear. Heat water, spin a turbine. Energy where you want it, when you want it.

1. https://www.vox.com/videos/22685707/climate-change-clean-ene...

Re: What is a molten salt reactor?

#29

Post by ortusdux »

m0llusk wrote: post #19

This boldly claims that molten salt reactors are safe, but my understanding is that these systems require carefully engineered coatings to function and that in practice every such system has leaked liquid sodium. The statement may be essentially true kind of like saying elevators are safe, but there is still room for risk analysis and expectation of occasional failures.

I've been working on molten salt reactor claddings for a few years now. MSRs are very safe.

First, there are two main groups of molten salt systems. One group uses generic salt to transport heat. This usually provides efficiency gains over water based systems. These are the systems that might leak sodium and it's no big deal.

The 2nd kind of system uses a salt with the fissile material dissolved in it. This is what the article is about. Leaks in these systems are not an option. The molten salt in this case slowly attacks any metal it comes in contact with. The tanks, tubes, etc. are designed with a large safety margin and constantly monitored. The salt chemistry is also monitored for signs of the materials the storage vessel is made of.

Re: What is a molten salt reactor?

#30

Post by a9h74j »

ncmncm wrote: post #27
pydry wrote: post #23

Earlier quoted context omitted.

Where?

Usually Finland is mentioned. Norway has hydro, anyway. Archangelsk, Kamchatka, Siberia, Fairbanks. McMurdo Station. There are places. They seem to do OK importing liquid fuel. Dunno why they would have to stop.

This just released: How Finland can plan to phase out fossil fuels

https://tupa.gtk.fi/raportti/arkisto/18_2022.pdf

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