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Molten Salt Reactors

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Re: Molten Salt Reactors

#41

Post by remontoire »

kragen wrote: post #29
remontoire wrote: post #27

Earlier quoted context omitted.

I was very disappointed, expecting you to show something about storage costs, but you just handwave that part, even though you go into very specific numbers and extrapolation for the actual pv's. May I suggest this is a major blindspot and probably where it completely falls down?

I don't know enough about storage costs to calculate them well, although several recent low-priced PV power-purchase agreements have included storage components, including the one we're talking about here. I look forward to seeing your calculations!

I don't know the calculation either, and have been trying to get hard numbers on various potential large scale storage such as https://en.wikipedia.org/wiki/Thermal_energy_storage and Lithium ion, as well as some sort of learning curve for costs. So far I've found a pretty compelling and well backed case for solar, but the storage component is always hand waved.

Re: Molten Salt Reactors

#42

Post by dgudkov »

ajross wrote: post #20
AtlasBarfed wrote: post #19

I thought LIFTR was the coolest thing ever. MSRs could have revolutionized power generation... about two decades ago. Solar/Wind/Storage are beating almost everything. Everything they aren't... they will, very soon. It's possible that MSRs could be scaled down and their liquid nature means that the reactor could simply be replaced on a schedule and the entire old reactor "reprocessed". But the investment won't be the…

This is exactly the issue. Nuclear simply missed the boat. It couldn't win against coal on a balance sheet and it's surely not going to catch up to renewables now. There's nothing wrong with it. A cheap fission technology would be a good thing. But at this stage literally no one is interesting in throwing money at a technology that is now into its eighth (!) decade of maturity. The low hanging fruit got picked by our…

>It couldn't win against coal on a balance sheet

It did win against coal on a balance sheet. It's the environmental concerns that stopped nuclear from proliferation, not the economical.

Re: Molten Salt Reactors

#43

Post by sandGorgon »

sien wrote: post #33
sandGorgon wrote: post #30

The largest reserves of thorium exist in India and China - two of the most energy hungry and polluting economies. One is on the UN Security Council and the other has a unique waiver from the US Congress on proliferation - so fissile material production is not the primary concern. Both India and China have massive deployments of renewable energy, yet the demand for energy is outstripping projected build-out. LTFR is g…

https://en.wikipedia.org/wiki/Occurrence_of_thorium From there it seems like India, Australia & the US all have large thorium reserves. There is certainly heaps of it.

not disagreeing. however, the hunger for energy in India and China is causing outsize investments in MSR.

For example - https://www.nextbigfuture.com/2017/12/china-spending-us3-3-b...

Re: Molten Salt Reactors

#44

Post by achalhp »

acidburnNSA wrote: post #17
achalhp wrote: post #16

Earlier quoted context omitted.

Firstly heat from inefficient low temperature solid-fuel reactors can't be used directly for many applications. So consider electricity. Cars/planes/kitchen-stoves cant use uranium or nuclear heat!! All 4.5 billion tons can't be extratcted. More we extract, concentration decreases and harder it gets. I keep asking this question: If seawater extraction of metals is practical, why aren't we extracting other costly meta…

Don't confuse solid fuel with traditional light water reactors. The highest temperature reactors are triso fueled helium cooled solid fuel reactors like HTTR with outlet temperatures over 1000C. Also, fast breeder reactors with solid fuel are just as sustainable as any fluid fuel breeder. Molten salt is one of about a dozen advanced reactor techs that has huge potential. Hard part is economics. Hazardous coolant has…

Highest temperature fission reactors are the gas core (vapor core) and ion core reactors. They are fluid-fuel reactors, but not demonstrated. Currently solid-fuel reactors hold the record for highest temperatures.

Fusion reactor runs hotter and again fuel is in fluid state.(Fluid: Liquid, gas & plasma.). But only runs for 10-100 minutes. Demonstrated fission reactors run for thousands of hours continuously.

Re: Molten Salt Reactors

#45

Post by kragen »

alex_young wrote: post #36
kragen wrote: post #29

Earlier quoted context omitted.

I don't know enough about storage costs to calculate them well, although several recent low-priced PV power-purchase agreements have included storage components, including the one we're talking about here. I look forward to seeing your calculations!

Perhaps this is hard to calculate because it's unbounded? Typically: Known costs for (anything) Maybe there's something wrong with my math?

Well, sure, storage costs depend in part on how long you have to store the energy, and how often. But surely someone has computed some kind of curve about how much storage is needed for PV to displace increasingly large percentages of peaker and baseload generation, assuming no demand response or other stabilization measures like rolling blackouts?

Re: Molten Salt Reactors

#46

Post by Marazan »

AnthonyMouse wrote: post #35
pfdietz wrote: post #22

Earlier quoted context omitted.

Nuclear is not a great complement to PV, if the PV is cheap. Cheap PV expands until there is no residual baseload demand left. At that point, nuclear power plants cannot maintain high capacity factor and their economics go all to hell.

Nuclear has effectively zero unit cost, it's all fixed cost. Once you build the reactor, you generate at full capacity all day and night and take whatever the market rate is. That means you get paid less during the day when solar is the cheapest provider, but you still match its price and supply your full generation capacity even then, because you can, because anything is more than nothing and the incremental generat…

No

Re: Molten Salt Reactors

#47

Post by steve1011 »

Marazan wrote: post #46
AnthonyMouse wrote: post #35

Earlier quoted context omitted.

Nuclear has effectively zero unit cost, it's all fixed cost. Once you build the reactor, you generate at full capacity all day and night and take whatever the market rate is. That means you get paid less during the day when solar is the cheapest provider, but you still match its price and supply your full generation capacity even then, because you can, because anything is more than nothing and the incremental generat…

No

good point lol

Re: Molten Salt Reactors

#48

Post by darkpuma »

TaylorAlexander wrote: post #24
ambicapter wrote: post #13

Earlier quoted context omitted.

Is it a hard robotics problem or a hard radiation-hardening problem?

Completely robotically maintaining a complex machine sounds like a hard robotics problem to me. Of course it can be designed for machine manipulation but that seems like a pretty complex fusion of robotics and nuclear reactor design. So I think it would be a lot of work.

It seems to me that the simplest reactors tend to be the most dangerous. I'm thinking of the Windscale fire and SL-1 in particular. One of the theories for what went wrong at SL-1 is that it was a murder-suicide, caused by the man tasked with physically manipulating the control rods of the reactor. I think robotic control is better for something like that. Robots are more predictable.

One of the aggravating factors at Windscale was their inability to perform maintenance tasks behind the reactor. They had canisters of radioactive material smashing open behind the reactor and it took them ages to even notice. That was a very simple reactor design; basically a nuclear pile. It was also an awful design that was irradiating England even before it caught fire.

Re: Molten Salt Reactors

#49

Post by dredmorbius »

PopeDotNinja wrote: post #18
achalhp wrote: post #16

Earlier quoted context omitted.

Firstly heat from inefficient low temperature solid-fuel reactors can't be used directly for many applications. So consider electricity. Cars/planes/kitchen-stoves cant use uranium or nuclear heat!! All 4.5 billion tons can't be extratcted. More we extract, concentration decreases and harder it gets. I keep asking this question: If seawater extraction of metals is practical, why aren't we extracting other costly meta…

One could make a pedantic argument that a battery powered anything can use nuclear, but I agree with your point.

There's no likelihood of batteries scaling to certain uses, such as large long-distance air transport, or marine shipping. Most trucking as well.

We either stop using those transport modes, or revert to prior forms (wind), or wire-based electrical systems (rail, canals, trucks).

Re: Molten Salt Reactors

#50

Post by jillesvangurp »

acidburnNSA wrote: post #38
jillesvangurp wrote: post #32

The elephant in the room with any kind of fission reactor is that they are going to need a lot of security. Even when the fuel and waste product is not weapons grade uranium, it's still highly radioactive and a great source of material for a dirty bomb. Basically anything that goes boom combined with small amounts of radioactive material and a bit of wind is a great way to depopulate e.g. large cities. So, having lot…

Are you suggesting that variable renewables plus batteries will approach prices that are... too cheap to meter? Looking at current cost VRE trends, when variable sources contribute up to 4% of world energy, and surrounded by massive amounts of cheap but high-carbon natural gas, and assuming that the trends will just continue exponentially downward without serious complication, is optimistic. Cost of integration of va…

Yes. Not indefinitely of course but we've seen nothing yet and there's enough in the research pipeline to suggest clear trends over the next two decades in terms of cost improvements, efficiency improvements, cheaper materials, etc. That 4% you mention was less than 1% not so long ago and will be closer to 40% not too long from now. Such is the nature of exponentials.

IMHO 5X cost reduction is basically a done deal even just applying simple economies of scale. You can argue whether this happens in five or ten years maybe but arguing it isn't happening seems futile. Beyond that, 10x is extremely likely to happen as well. There's a lot of research happening that would need to be a complete failure/waste of time for that to not happen. At worst it will happen slower that I might like. Maybe this happens over the next decade. Or two. Or three even. From there, 20x might be quite possible as well.

Beyond that we're indeed talking rapidly diminishing returns. 10X would mean 0.2 cent/kwh. 20x would cut that to about 0.1 cent. This indeed gets you in to territory where metering it becomes more expensive than is worth the trouble. The average household uses about 15000 kwh per year, or about 150$ worth of energy at these prices; much less outside the US. Much of that is going to be produced on people's roofs or in their back yards. At that point it turns into a fixed cost.

Historically the same sources producing the studies you are referencing have been off by magnitudes predicting current adoption and prices for both solar and wind. So, I'd consider that the pessimist glass half empty point of view. Not to dismiss it entirely but arguing cost increases seems a bit far fetched in light of current trends in the market.

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