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What is a molten salt reactor?

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Re: What is a molten salt reactor?

#31

Post by jeffbee »

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 don't know if they are safe or not but one thing that disturbs me about neo-fission propaganda is how they so nonchalantly dismiss what seem to me to be threats worth discussing. For example, MSR fans will say that they operate at standard pressure, and therefore can't rupture. Also, gaseous fission products are removed continuously. OK but what about the gaseous fission products if the removal system ceases to function? Then what about the pressure? Same question about water. MSRs are safer because they contain no water, which can't flash to steam and explode. OK, but what about water intrusion on the surprisingly wet planet Earth? What if the reactor is flooded? Would a flooded reactor stop the passive safety plug from melting?

I always had the same suspicions about the pebble bed reactor boosters. That was a design that was always sold as being inherently safe and self-moderating, with the huge, huge asterisk that if any oxygen or water ever gets anywhere near the fuel the whole thing will explode and then catch on fire, which seems like a pretty severe drawback. Any time you see a claim that a reactor vessel "does not contain" either water or oxygen, just mentally translate that to "is not designed to contain" or "does not initially contain" before reading further.

Re: What is a molten salt reactor?

#32

Post by matt_the_bass »

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 came across this topic when I read about a proposed MSR powered ship. I’ve yet to see a solution for powering ships via renewables. Ships also require a relatively small reactor (since they are only powering the ship) compared to a land based reactor which will power a region. So this could be the use case needed to bring such tech to fruition.

Re: What is a molten salt reactor?

#33

Post by socialdemocrat »

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.

It is worth pursuing solutions like Moltex though because eventually we need to find a replacement for the gas power plants which will be backing up wind and solar.

Pumped hydro, cryogenic storage, thermal storage, batteries, green hydrogen etc may tackle a lot of that but we simply don’t know what solution will end of working best.

Wind and solar has to be primary focus for the next 10-15 years but once we reach 60-70% of the grid being renewable you cannot really go much further. Solutions which can deliver power on demand will be crucial. If MSR guys can get stuff going within 10 years then they may be part of the solution.

Re: What is a molten salt reactor?

#34

Post by socialdemocrat »

matt_the_bass wrote: post #32
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 came across this topic when I read about a proposed MSR powered ship. I’ve yet to see a solution for powering ships via renewables. Ships also require a relatively small reactor (since they are only powering the ship) compared to a land based reactor which will power a region. So this could be the use case needed to bring such tech to fruition.

Ships are not that complex to solve. You could use a combination of batteries, green hydrogen and/or synthetic fuels.

Ships with reactors will not work. That will turn into a paperwork nightmare in every harbor it enters.

Re: What is a molten salt reactor?

#35

Post by ncmncm »

inglor_cz wrote: post #22
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 w…

Storage cost is falling even faster than wind or solar did.

Re: What is a molten salt reactor?

#36

Post by ncmncm »

Manuel_D wrote: post #28
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, renewa…

Not true. Storage is not built out because you need a lot more top-line renewable generating capacity, to charge it from, to make it worth building. So, the money is overwhelmingly-better spent on generating capacity, meantime. Thus, it is being spent there.

Storage cost is falling even faster than solar or wind ever did. Some storage pilot projects have been abandoned as alternatives undercut them, as happened to concentrated-solar when fixed-PV cost fell below the cost of tracking mirrors.

But you have already had this explained to you, several times over. Pretending not to know about it is not a good look.

Re: What is a molten salt reactor?

#37

Post by zbrozek »

Manuel_D wrote: post #7
dane-pgp wrote: post #3

Earlier quoted context omitted.

> The way modern society is going, a LOT of power is going to be required What do you mean by "modern society"? According to the IEA, "energy demand per capita is likely to remain at current levels for the next 25 years. In other [words], peak per capita energy consumption may have already arrived".[0] Most "modern societies" have less than replacement fertility levels, so energy use is only increasing because the po…

Energy per capita, yes. But electricity per capital not necessarily. Things like smelting, shipping, and air travel, all of which depends on fossil fuel must be electrified.

I'm actively trying to drive down my marginal cost of electricity explicitly so I can use more of it to make my life better. I am absolutely driving up my total energy consumption, not just switching fuels.

Re: What is a molten salt reactor?

#38

Post by ncmncm »

socialdemocrat wrote: post #33
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.

It is worth pursuing solutions like Moltex though because eventually we need to find a replacement for the gas power plants which will be backing up wind and solar. Pumped hydro, cryogenic storage, thermal storage, batteries, green hydrogen etc may tackle a lot of that but we simply don’t know what solution will end of working best. Wind and solar has to be primary focus for the next 10-15 years but once we reach 60-…

Existing peaker plants will burn synthetic ammonia or hydrogen, once there is enough spare renewable generating capacity to synthesize that. In the meantime, we build out the renewable generating capacity. Then we build out hydrogen and ammonia synthesis.

There is no place for nukes in the inner solar system. Out Jupiter and beyond, ok.

Re: What is a molten salt reactor?

#39

Post by Manuel_D »

ncmncm wrote: post #36
Manuel_D wrote: post #28

Earlier quoted context omitted.

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, renewa…

Not true. Storage is not built out because you need a lot more top-line renewable generating capacity, to charge it from, to make it worth building. So, the money is overwhelmingly-better spent on generating capacity, meantime. Thus, it is being spent there. Storage cost is falling even faster than solar or wind ever did. Some storage pilot projects have been abandoned as alternatives undercut them, as happened to co…

The goal of the Paris accords is to have zero emissions by 2050. Not just zero emissions from electricity, but all emissions eliminated: transportation, industry, and heating too. Just the electricity usages amounts to 500 GWh per hour for the US and 2.5 TW globally. Storing even just 4 hours of storage (a modest goal, many renewable plans call for days of storage) is outside the scope of anything we could deliver through existing options.

The plan for renewables is to build until saturation is reached, then burn gas while we cross our fingers and hope that an invention makes storage effectively free.

Re: What is a molten salt reactor?

#40

Post by ncmncm »

matt_the_bass wrote: post #32
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 came across this topic when I read about a proposed MSR powered ship. I’ve yet to see a solution for powering ships via renewables. Ships also require a relatively small reactor (since they are only powering the ship) compared to a land based reactor which will power a region. So this could be the use case needed to bring such tech to fruition.

Ships will be retrofitted to tank and burn ammonia in existing engines. Ammonia liquifies at room temperature under low pressure.

The conversion will be accelerated by restrictions on docking bunker-oil burners.

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