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Molten Salt Reactors

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Re: Molten Salt Reactors

#51

Post by Mirioron »

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…

Renewables have the problem that the larger the portion of your power that's generated through these renewables, the exponentially more storage you need. It's not a linear relationship, because you can have weather that doesn't cooperate for long periods of time, but the power can't go out.

Another issue is that solar and wind aren't really suitable everywhere. The further north you go the less economical solar becomes. A large chunk of Europe sits further north than the US.

Re: Molten Salt Reactors

#52

Post by audunw »

Mirioron wrote: post #51
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…

Renewables have the problem that the larger the portion of your power that's generated through these renewables, the exponentially more storage you need. It's not a linear relationship, because you can have weather that doesn't cooperate for long periods of time, but the power can't go out. Another issue is that solar and wind aren't really suitable everywhere. The further north you go the less economical solar becom…

What’s happening right now is that renewables are being paired with an increasing number of gas power plants. Since gas power can ramp up so quickly they’re a good match until storage can take over.

So I think we already have the solution to the problem you’re describing: just pay to maintain a decent amount of the existing gas power plant. If they’re only there for backup, the impact on CO2 emissions will be negligible. You could even make the gas from renewable sources, since in this scenario the cost of the gas itself is negligible compared to cost of keeping the power plant operational.

This is incidentally another reason (current) nuclear is a dead end going forward. They’re a bad match for renewables. What we need isn’t more base load, we need more peaker plants, load following plants, backup plants and energy storage. Nuclear isn’t a good solution in any of these categories.

Re: Molten Salt Reactors

#53

Post by olejorgenb »

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!

It would be very interesting to see what kind of storage capacity these agreements specify

Re: Molten Salt Reactors

#54

Post by Mirioron »

jillesvangurp wrote: post #50
acidburnNSA wrote: post #38

Earlier quoted context omitted.

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 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 need redundancy. As the market share of solar and wind grows we will need to increase the amount of storage and power generation far beyond what we normally need to operate.

Let's say you have a city that uses 1 GWh of electricity per day. If you were to generate all the electricity with natural gas then you need to have 1 GWh plus some extra for redundancy to fulfill the needs of the city. If you generate 5% with solar and the rest with natural gas then nothing really changes. If the weather is bad then the natural gas plant will step in.

As the share of your solar power generation grows toil need more and more redundant storage and solar power generation. If you rely 100% on solar power generation and the weather can be bad for a week in a row over the city, then you'll need storage that will last for more than that entire week. Not only that, you'll also need extra power generation capability to be able to fill and maintain that storage.

Just to put this into perspective: the US uses about 10 TWh of electricity per day.

Re: Molten Salt Reactors

#55

Post by ivanhoe »

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). To partially solve this you can concentrate solar into large solar farms, but than you have a problem with the space available, you need a lot of land for that - which is perhaps less of a problems in US or Australia or Africa, but in densely populated areas like Europe (which is also located more to the North and gets less sun) or Japan this creates problems. Also there is an issue that our climate is changing and becoming more and more unstable, which could cause lots of engineering and exploitation problems for renewables (hurricanes, hail storms, unexpected drops in temperature and periods of bad weather like this summer in Europe in May). So I don't think it's (yet) all that certain which is the best way to go long-term, and IMHO the clear win of renewables is more a picture painted by media than a solid science.

Re: Molten Salt Reactors

#56

Post by sampo »

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…

> Solar/Wind/Storage are beating almost everything.

Does anyone have numbers, how fast (yearly added kWh per capita) has any country built solar+wind lately? Or plans to build in the near future? When Sweden built nuclear in 1976–1986, they added 640 kWh per capita per year. Will some country or state beat that record?

Source: this figure

https://science.sciencemag.org/content/sci/353/6299/547/F2.l...

in this article

https://science.sciencemag.org/content/353/6299/547

Re: Molten Salt Reactors

#57

Post by jabl »

jillesvangurp wrote: post #50
acidburnNSA wrote: post #38

Earlier quoted context omitted.

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 e…

> 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.

But such is not the nature of the logistic function, which is usually a more accurate model of how technologies penetrate. (yes, in the beginning it looks like an exponential)

Re: Molten Salt Reactors

#58

Post by Reason077 »

Mirioron wrote: post #51
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…

Renewables have the problem that the larger the portion of your power that's generated through these renewables, the exponentially more storage you need. It's not a linear relationship, because you can have weather that doesn't cooperate for long periods of time, but the power can't go out. Another issue is that solar and wind aren't really suitable everywhere. The further north you go the less economical solar becom…

Solar is getting so cheap that it's becoming economical in places that might surprise you.

The UK sits further north than almost all of the USA (excl. Alaska), and has a climate not exactly known for its abundant sunshine. But large-scale solar farms are now commercially viable here without subsidy. (eg: https://www.clevehillsolar.com)

Re: Molten Salt Reactors

#59

Post by Tuna-Fish »

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 can't track the sun

We are well past the point where tracking the sun was desirable. The apparatus that allows solar panels to track the sun is now much more expensive, especially when you consider the maintenance costs, than just using more static panels.

Re: Molten Salt Reactors

#60

Post by olejorgenb »

audunw wrote: post #52
Mirioron wrote: post #51

Earlier quoted context omitted.

Renewables have the problem that the larger the portion of your power that's generated through these renewables, the exponentially more storage you need. It's not a linear relationship, because you can have weather that doesn't cooperate for long periods of time, but the power can't go out. Another issue is that solar and wind aren't really suitable everywhere. The further north you go the less economical solar becom…

What’s happening right now is that renewables are being paired with an increasing number of gas power plants. Since gas power can ramp up so quickly they’re a good match until storage can take over. So I think we already have the solution to the problem you’re describing: just pay to maintain a decent amount of the existing gas power plant. If they’re only there for backup, the impact on CO2 emissions will be negligi…

Any increase in base load would reduce the amount of renewable+gas/storage capacity needed, so at worst it's a neutral match for renewables.
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