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Smaller reactors bring nuclear power closer to fulfilling its promise

nature.com

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Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#121

Post by ViewTrick1002 »

chickenbig wrote: post #113
mayama wrote: post #41

Earlier quoted context omitted.

> Even if its cheaper to build small reactor vessels, MANY of the other costs become more expensive in larger numbers. There is no way SMR could beat solar+battery power cost even now. With sodium and other batteries projected to reduce storage cost, it is even more unlikely that SMR could be price competitive in future grids. SMR is the only way that dying western nuclear industry could attempt to deal with ballooni…

> There is no way SMR could beat solar+battery power cost even now. Not a particular fan of this paper, but it does illustrate a point ... https://ieeexplore.ieee.org/document/8867359 showed that for the UK to go 100% solar it would need an energy capacity of 1/3 of the total grid energy demand over the year. Figure 6 A shows the big trend of 6 1/2 months of discharge and 5 1/2 months of charge (i.e. cycle perhaps on…

Not sure what relevancy a 2019 paper has today?

It also seems like they are constraining the system to have no overproduction.

It’s like assuming that a fossil based system has all its producers generating the expected capacity factor and then smoothing out the season and daily demand changes with storage. Due to the difference between summer and winter demand such a fossil system would also need to have months of storage to compensate.

Which of course is absolute stupidity. When you can just overbuild production capacity and leave a far simpler problem to solve.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#122

Post by bryan0 »

pfdietz wrote: post #59
briffle wrote: post #58

Earlier quoted context omitted.

> If it's so much cheaper to build multiple small reactors, just build one big plant with 24 small reactors. That is literally the plan with several designs like NuScale (and I think TerraPower). The plan with NuScale is to ship the reactors on rail or barge, and then truck it in the last few miles. So they cost savings is in not having to custom desgin the actual components for each site, and build them on site. Sta…

NuScale infamously failed to get their reactor funded in Utah (UAMPS and the CFPP), it was just too expensive. Costs kept rising, large utilities declined to sign up, and in the end those utilities remaining were going to hit the contractual off ramp so it was just cancelled. I have some links to minutes of municipal utility meetings in Idaho Falls that showed the wheels coming off (even though there was great local…

> Their design appears to have it roots in the (false) idea that what was holding back nuclear was perception of safety, rather than cost.

And why do you think they cost so much? Because people need to believe they are safe from catastrophic failure

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#123

Post by marshray »

will5421 wrote: post #110
stymaar wrote: post #106

Earlier quoted context omitted.

> there is new geothermal power companies getting funding and are transitioning from pilot projects to production. If geothermal works economically (outside of volcanic zones where it already does) then it's game over for any other power source except existing dams though because it solves all problems at once. That'd be a great thing for humanity but I don't think it's worth stopping pursuing alternatives already, b…

Won’t geothermal cool the Earth’s core?

Not the core measurably, but my understanding is that it can very slowly cool the volume of earth immediately around the heat extraction site.

I have full faith in modern engineers' ability to account for these effects in the plant designs.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#124

Post by to11mtm »

elcritch wrote: post #79
mayama wrote: post #41

Earlier quoted context omitted.

> Even if its cheaper to build small reactor vessels, MANY of the other costs become more expensive in larger numbers. There is no way SMR could beat solar+battery power cost even now. With sodium and other batteries projected to reduce storage cost, it is even more unlikely that SMR could be price competitive in future grids. SMR is the only way that dying western nuclear industry could attempt to deal with ballooni…

If solar+battery were cheaper wouldn't the new AI data centers be opting to pay to build that rather than nuclear or LPG options?

Nuclear, FBOW, has one big advantage.

Namely, It's very easy to 'design to load' where you don't need to worry about the next shipment of Coal, or an extended weather event causing excessive cloud cover and depleting your reserves.

Heck, even as far as compared to LPG, you don't have to worry as much about disruptions or possible cost shifts around LPG supply.

Yes, I'm possibly tongue-in-cheek handwaving specific types of 'weather events' here and potential impacts, i.e. Tsunamis... OTOH it's a lot easier in current gen designs to make something that would have minimal risk for something, say, in the middle of nowhere Texas.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#125

Post by ViewTrick1002 »

idiotsecant wrote: post #116
bryanlarsen wrote: post #80

Earlier quoted context omitted.

The most cost efficient new-build grid is 90-98% solar/wind/battery depending on your locales insolation & wind coverage. (Source Ember Energy) The remaining 2-10% is nat gas, if you have a piped source, or coal if you don't. But 98% renewable doesn't mean you can hit 100% by adding 2% more of something else, it means your something else has to supply ~100% of the power 2% of the time. If China is aiming for that cos…

Solar battery is not by any stretch of any possible definition the cheapest generation to deploy. Not even close. We do a disservice to the entire conversation saying easily falsifiable things like that. At 90% penetration solar + battery has a LFSCOE somewhere around $800/mwh depending on the study. Natural gas is something like 30-60. Solar panels are cheap. Building the required transmission and storage to service…

Please, don’t cite the LFSCOE paper again. Citing it shows you have a beef against renewables.

That paper uses one renewable source, like only solar, and 2018-19 cost data for storage.

A real grid is made up of a mix of sources, which is why the research lately has focused on system costs.

All those analyses find that renewable grids are far cheaper than if involving new built nuclear power.

Here are two modern papers on the subject:

https://www.csiro.au/-/media/Energy/GenCost-2025-26-Final/Ge...

https://www.sciencedirect.com/science/article/pii/S036054422...

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#126

Post by istjohn »

soco wrote: post #3

With solar and batteries getting cheaper and cheaper, is this still a topic? Or at least for the time being until that "cheaper" gets cheaper enough?

It is if the nuclear industry pays for it to be. See the disclaimer at the bottom of the article.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#127

Post by emsign »

The future will be solar. Especially in underdeveloped regions without a centralized power grid, solar makes the most sense. And even in developed countries having solar panels on your roof and a battery in your cellar is the most cost effective way of getting all your electricity needs.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#128

Post by istjohn »

fpoling wrote: post #108
fasterik wrote: post #38

Earlier quoted context omitted.

The problem with 100% solar+batteries is that you need to massively overbuild for the system to meet demand. It's far more cost-effective to have some portion of generation come from a firm, weather-independent source. The main options are fossil fuels, hydro, geothermal, and nuclear. Since fossil fuels emit carbon and hydro and geothermal are geographically limited, nuclear is the best option in a lot of places.

If solar becomes 2 times cheaper, it will be economical to capture nitrogen from atmosphere and produce ammonia and use that for long-term energy storage and fuel. And with that one does not need massive solar overbuild. This does not require any magic technology, just scaling up what is available today is enough and will definitely happen within the next 20 years, before small nuclear will have any effect.

If I recall correctly solar panels are already so cheap that to halve the installed cost again will require most of the efficiencies to be found in other costs like manufacture of associated hardware and equipment and installation. I don't know if those costs will be so easy to reduce.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#129

Post by thinkcontext »

briffle wrote: post #58
hwillis wrote: post #14

And a contrasting article from IEEE: https://spectrum.ieee.org/the-forgotten-history-of-small-nuc... > Samuel B. Morris, the general manager and chief engineer of Los Angeles’s Department of Water and Power, traveled all the way to Geneva in 1955 to attend the first International Conference on the Peaceful Uses of Atomic Energy. There, he made a case for small reactors, arguing that because the “number of small units…

> If it's so much cheaper to build multiple small reactors, just build one big plant with 24 small reactors. That is literally the plan with several designs like NuScale (and I think TerraPower). The plan with NuScale is to ship the reactors on rail or barge, and then truck it in the last few miles. So they cost savings is in not having to custom desgin the actual components for each site, and build them on site. Sta…

NuScale is a terrible example. Their flagship project collapsed before it even started because of cost escalation and their other project was some sort of crypto scam.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#130

Post by marshray »

mchusma wrote: post #78
briffle wrote: post #58

Earlier quoted context omitted.

> If it's so much cheaper to build multiple small reactors, just build one big plant with 24 small reactors. That is literally the plan with several designs like NuScale (and I think TerraPower). The plan with NuScale is to ship the reactors on rail or barge, and then truck it in the last few miles. So they cost savings is in not having to custom desgin the actual components for each site, and build them on site. Sta…

> If it's so much cheaper to build multiple small reactors, just build one big plant with 24 small reactors. The biggest costs to nuclear are associated with each of them being unique snowflakes. They need to be standardized and mass produced to bring down costs. So the dream is many big plants (eg starting 10+ per year), which is what France did and China does, but since we can’t seem to have that here, small reacto…

Most of the reactors we have in the US today are the result of building many of a few models per year during the late 1960's - early 1970's.

In 1974, 12 reactors entered commercial operation and 13 more were begun.

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

The technology was given almost a century to prove itself cost-effective. It did not succeed in the market and only ever worked with truly massive amounts of government subsidies.

High fixed costs + more reactor sites -> more expensive, more nuclear waste sites for taxpayers to clean up

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