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Molten Salt Reactors

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Re: Molten Salt Reactors

#61

Post by _0w8t »

Mirioron wrote: post #54
jillesvangurp wrote: post #50

Earlier quoted context omitted.

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 e…

Aren't roof solar panels very inefficient? They can't track the sun and you can't have good density from them either. Furthermore, they don't work for office buildings and apartment buildings. > Not to dismiss it entirely but arguing cost increases seems a bit far fetched in light of current trends in the market. I think what the parent was saying is that because solar and wind don't reliably produce energy, we will…

With dirt-cheap renewables it will be more efficient to generate methanol from solar or wind electricity and to use it for long-term storage and redundancy than to burn natural gas or coal. And compared with coal or natural gas with methanol one can use fuel cells to convert it to electricity so one can have relatively small plants for backups in case of really long strips of bad weather.

Re: Molten Salt Reactors

#62

Post by jillesvangurp »

Mirioron wrote: post #54
jillesvangurp wrote: post #50

Earlier quoted context omitted.

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 e…

Aren't roof solar panels very inefficient? They can't track the sun and you can't have good density from them either. Furthermore, they don't work for office buildings and apartment buildings. > Not to dismiss it entirely but arguing cost increases seems a bit far fetched in light of current trends in the market. I think what the parent was saying is that because solar and wind don't reliably produce energy, we will…

> Aren't roof solar panels very inefficient?

They are good enough. Low efficiency just means we have to buy more of them. Obviously we'd need solar plants (and maybe wind parks and other clean sources) to also power those with limited access to roof surface.

Of course, bad weather doesn't mean solar stops working; it just reduces the output. The effect is typically very local as well. So, all that means is that you need a bit extra capacity to cover for that or import energy from somewhere else where the weather isn't miserable.

When (not if) the price for solar and wind drops 10x, you'll be able to buy 10x more than what you need and still beat coal/gas/nuclear on price. 10x is an insane safety margin that would mean you produce more than you need even on the most cold, dark, and miserable day imaginable. And of course solar is not the only source of clean cheap energy. Wind would be another popular option.

Re: Molten Salt Reactors

#63

Post by _0w8t »

ivanhoe wrote: post #55
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…

The cost of manufacturing energy is not the only cost when you need to distribute energy on a large scale. Electrical grids are prone to oscillations and having less and bigger power sources makes things a lot easier and more reliable (and that means cheaper also). You can store energy but that again increases complexity of the grid and costs (even super-cheap storage will always be more expensive than no storage). T…

Grids must be very stable because there is no storage at the end points. If electricity consumers are very OK to be without electricity for few hours per day that alone makes grid much cheaper.

Re: Molten Salt Reactors

#64

Post by wffurr »

dgudkov wrote: post #42
ajross wrote: post #20

Earlier quoted context omitted.

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.

And the environmental costs for nuclear were internalized by regulation, while the same did not happen for coal. This is still well within the realm of economics.

Re: Molten Salt Reactors

#65

Post by wffurr »

dredmorbius wrote: post #49
PopeDotNinja wrote: post #18

Earlier quoted context omitted.

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).

Or make fuel. There are all sorts of ways to make carbon neutral diesel and jet fuel. They just aren't economic compared to pumping it out of the ground unless the externalities of burning virgin fuels are priced in with regulation.

Re: Molten Salt Reactors

#66

Post by pweezy »

> Molten salt fuels were first conceived of in the late 1940s, when people began thinking of nuclear powered airplanes! > The idea was to have very long range bombers in the air at all times

I had never heard of this idea, and thought it was super interesting. Imagine aircraft that could stay in the air indefinitely (for some practical purposes), carrying massive loads without fuel being a concern.

Similar to nuclear aircraft carriers and submarines, at least conceptually.

https://en.m.wikipedia.org/wiki/Nuclear-powered_aircraft

Re: Molten Salt Reactors

#68

Post by tim333 »

darkpuma wrote: post #48
TaylorAlexander wrote: post #24

Earlier quoted context omitted.

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 a…

The Windscale reactors were built in a hurry in 1950 to produce nuclear weapons after Russia managed to test it's first atom bomb in 1949 and are not really representative of modern power generating technology.

Re: Molten Salt Reactors

#69

Post by pfdietz »

AnthonyMouse wrote: post #37
pfdietz wrote: post #23

Earlier quoted context omitted.

Studies that purport to show that nuclear has a place due to inability of renewables to fill those gaps are usually assuming renewables + short term storage cannot fill those gaps. But renewables + short term storage + hydrogen can, and probably more cheaply than a system with nuclear reactors.

What's hydrogen supposed to add? It's just a type of storage, and probably not even the cheapest one.

Hydrogen has low capital cost. The capital cost/energy of storing hydrogen underground will be much less than the cost of storing that energy in a battery. If you have a storage scenario where the energy is stored for very long times, there will be few cycles of that system over its economic lifespan, so minimizing capital cost (even if that means much lower round trip efficiency) is very important.

One would still use more efficient short term storage (and over-installation of renewables sources) for diurnal load leveling.

Hydrogen can also be turned back to electrical power (at lousy efficiency) with cheap hardware. In particular, simple cycle gas turbine power plants with efficiency of 40% cost maybe $400/kW. Compare this to $8-10K/kW for a new nuclear power plant.

Re: Molten Salt Reactors

#70

Post by pfdietz »

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…

"as long as the average price is above average cost"

And that's the killer. Add enough solar and wind and the average price craters, even if solar and wind cannot handle everything (without help from dispatchable sources and/or storage).

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