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> 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…is many times the number of large units,” there could be “economy in development and repetitive manufacture” of the small units.
> But nothing in the history of small nuclear reactors suggests that they would be more economical than full-size ones. In fact, the record is pretty clear: Without exception, small reactors cost too much for the little electricity they produced, the result of both their low output and their poor performance.
For me, SMRs don't pass the smell test. Buying one big plot of land for a reactor, building one power interconnect, having a localized water impact is way easier and cheaper than many. Even if its cheaper to build small reactor vessels, MANY of the other costs become more expensive in larger numbers. Costs that you can ignore while you're just building a prototype.
If it's so much cheaper to build multiple small reactors, just build one big plant with 24 small reactors. Thing is the nuclear reactor part is only 10-15% of the plants full cost: https://world-nuclear.org/information-library/economic-aspec...
Regulatory risk is too high, building too infrequent to understand costs, funding for first-of-its-kind is too hard for nuclear in most countries. SMR makes it fundable. New designs give the hope that regulatory burdens can be lowered.
Some things would depend on the specific location and the grid around it:
The Point Lepreau Nuclear Generating Station in New Brunswick may be 'overkill' because when it goes down every few years for inspections/retooling, there's little other redundancy available. SMRs would be useful for that regional grid: install 3-4 and one can go down with less fuss.
In (e.g.) Poland there were small/medium coal-fired generation stations near coal mines. If the mines are now empty (or retired for climate change), then the grid connections could be reused for SMRs on an existing generation site: less need to find a new site and build new power pylons, etc.
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 ballooning compliance and finance costs and hope for revival. China or India doesn't have this compliance cost and still build conventional nuclear.
Even for the SMR usecase that got funding recently, mega datacenter electricity, there is new geothermal power companies getting funding and are transitioning from pilot projects to production. Some are using tech that is already being used in oil fracking industry for decades, so new geothermal tech scaling up has far less roadblocks technology and compliance wise. So other than military and mobile civil applications like nuclear icebreaker, I don't see the chance of SMR succeeding anywhere else.
If you want to decarbonize as fast as possible, it makes sense to focus on rolling out wind/solar/battery as fast as possible for now, but keep developing nuclear technology to cover the last bit where it starts getting especially expensive to replace fossil with renewables without losing reliable power. That's exactly what China appears to be doing. They're not just building a few reactors, they're also the world leaders in developing various GenIV designs, like molten salt 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. Standard reactor, standard monitoring systems, standard control room able to monitor multiple reactors, etc.
Plus, when you have 12 of them onsite in one large area, you can take one offline for refueling, and still produce power with the rest of them.
Their design requires considerably more steel and concrete per MW(e) than a large conventional PWR power plant. You don't do civil construction in a factory, and that's where much of the cost is. Their design appears to have it roots in the (false) idea that what was holding back nuclear was perception of safety, rather than cost.
I'm concerned lax physical security will allow miscreants to blow them up and spread nuclear materials over a wide area. The ensuing panic would totally destroy any goodwill nuclear power has gained over the last 20 years or so.
I'm also concerned these things will mostly be used by Big Tech for their A.I. data-centers playing the Good Samaritan with their claims of "Carbon Neutral Environmentally Friendly A.I."
ConEd and Three Mile Island meltdown brought out a mass of normal people to chant "Hell No! We won't Glow!"
Hanford in Washington State.
San Onofre in So Cal.
Santa Susana Meltdown.
The reality is that everyone wants nuclear, but no one wants to live near a nuclear power plant.
I wouldn't be so sure about that (in the US).
Like usage in A.I. data-centers assumes
that they get price competitive with low quality gas turbines run by state subventioniere natural gas...
or the government actual enforces proper environmental protections so that they can't continue running gas turbines without proper filters (and this isn't even (mostly) about climate change, but air pollution harming people)
and from how it currently looks both things seem unlikely :/
Surely solar is orders of magnitude safer.
Depending on what kind of solar, it can have quite a high death/TWh ratio because people fall off roofs while installing them. As a ratio is far better now that so much new solar is ground level solar farms and not installed by amateurs or professionals who have a van, a ladder and watched a YouTube video that one time. Some older estimates based, I think, on generic roofing accident rates, were up to 0.44 deaths/TWh.
Wind is more dangerous than nuclear (0.04), I guess also from falls and accidents during construction and maintenance.
Edit: All are incredibly safe compared to the next worst, hydro (1.3, or 30 times worse than wind).
The Chernobyl exclusion zone will remain uninhabitable for the next 20,000 years.
Why is that a concern?
One option is to also mandatorily lock the powerplants to the municipal grid, and provide rebates to data center operators via net metering instead of simply giving them cash back.
But yes, the lax security and the laissez-faire don't give a shit attitude of the current admin far outweighs any of these benefits
[0] https://www.wired.com/2004/09/china-5/
https://en.wikipedia.org/wiki/AVR_reactor for instance, which suffered so many accidents that it was known as the "Shipwreck". It ended up with TRISO pebbles getting stuck in the reactor vessel, the primary circuit being hopelessly contaminated with fission products, and is now impossible to safely decommission using current technology.
It seems to me working SMRs really would be valuable, particularly for off-grid applications or where process heat is needed alongside electricity generation.
But as someone who was, like you, taken in by the pebble bed hype last time around, I've now learned to be much more sceptical about new nuclear technologies until they've actually been proven in practice.
The word should is doing some real heavy lifting there. Especially given the subject.
I guess we'll know in 2030 when one should come online.
But there's a real possibility when all this shakes out that SMR's only advantage will be their flexibility. And that might be enough. A major issue with gigawatt scale nuclear is that it's frankly too big for most markets. Only very large electric markets can can easily digest a new always-on 1000 megawatts of electricity, and you need to be building multiple plants at a time for this all to be economical. That's why the nuclear power rollout of the 60s through 80s worked, and why China and to a lesser extent India's nuclear industry is thriving presently.
With an SMRs smaller scale, there are just way more available projects where nuclear is feasible, and so a more consistent workload can keep everyone employed and subcontractor's backlogs filled. The flexibility in scaling lets you reclaim the benefits of having an experienced workforce and that knows how to build nuclear power plants, something we lost in the west when we stopped building them.
I'd guess many places in Africa could be potential markets that have underdeveloped grids but growing economies and populations. Hence the SMR industry in South Africa since the 90s I guess.
The next big market is actually replacement plants in the USA and Europe. Electricity generation may have peaked there, but much of the generating capacity is decades old and needs replacement. There are a lot of smaller facilities that are not gigawatt-scale that need to shut down, and it's easier to plug that gap with SMRs.
South and Central America are small markets, but they won't be ignored. There is a lot of complexity here with the inter-national hydro projects and broken up grids, so I'm sure some countries will look into SMRs.
Africa unfortunately just doesn't factor in except as a long-term possibility for growth. It's only 3% of electricity generation now, and its share will probably fall as Asia electrifies.
This is all worst-case scenario where SMRs are less financially competitive than current gigawatt-scale designs. If SMRs do actually succeed in being cheap assembly-line reactors, then all bets are off and the industry will experience explosive growth.
In theory we should start investing in synthetic fuel production, but it's been mostly vaporware so far.
"Oklo Corp. Logo Oklo is designing and deploying advanced fission power plants to provide clean, reliable, affordable energy"
You could probably just sink it all in the ocean near a subduction zone.
If you want to dispose of waste deep in the sea floor do it far away from subduction zones. Or just store it cheaply in dry casks and minimize the net present value of the cost of dealing with the waste.
Longer-term - it's mid-ocean ridges, not subduction zones, where you find all the volatiles and volcanoes. Yes, millions of years in the future, some micro-percentage of the subducted material will re-emerge, hundreds of miles away, via volcanoes. So will vastly more natural radioactivity, whether or not we dispose of nuclear waste in the subduction zone.
That's simply not true. Yes, there are volcanoes at mid-ocean ridges, but subduction zones also have plenty of activity.
https://en.wikipedia.org/wiki/Mud_volcano
"There are 10 active mud volcanoes in the Izu–Bonin–Mariana Arc which can be found along a north to south trend, parallel to the Mariana trench.[43] The material erupted at these mud volcanoes consists primarily of blue and green serpentinite mud which contains fresh and serpentinized peridotite material from the subduction channel. Fluid from the descending Pacific Plate is released by dehydration and alteration of rocks and sediment."
https://en.wikipedia.org/wiki/Volcanic_arc
(for description of how subduction zones create magmatic volcanoes)
Subducted material is very wet, and as it descends the volatiles ascend to melt the rock above, creating magma (water reduces the melting point of rocks just like it reduces the melting point of sugar.)
I ask because the last reactors the US brought online took so long to build and cost so much they caused the cost of power to go up.
This seems unworkable when solar is already causing power to be free (Australia), and gets cheaper by the day.
That's the opposite of what you want. You want something that is cost-effective to operate at a 10%, 1% or 0.1% duty cycle. Like nat gas or hydro. Not nuclear.
And overbuilding isn't the only lever you have to ensure coverage meets your target 99.99% level -- geographic diversity works really well (the wind is always blowing somewhere), and wind power production is usually negatively correlated with solar power production.
Yes, it does seem to still be a topic.
If this is the goal, they're failing spectacularly.
Edit: Per ChatGPT's calculation, nuclear is significantly cheaper than solar + battery in my country (Czech Republic) if we're talking about adding new reactors to existing power plants.
How many batteries do you need to power, say, entire Scandinavia during winter? That would be a lot of lithium, btw.
"Dunkelflaute" periods when it is dark and no wind to run the wind turbines are common in northern winters, IIRC the longest one a few years ago was 12 days long.
Which means that in order to have a reasonable buffer against it, you would need enough batteries to supply the entire region for three weeks. Not going to happen, unless we discover some much more efficient class of batteries.
Dunkelflaute's are a German phenomenon: the standard pattern in most of the world is that the high pressure systems that suppress winds are generally sunny. And the high elevation areas in Germany are sunny during a dunkelflaute.
IOW, batteries aren't the only answer required to cover a dunkelflaute.
https://web.archive.org/web/20250507123042/https://docs.nrel...
Major technology companies have signed strategic agreements for SMR development, but regulatory approvals and supply-chain scaling place widespread commercial deployment in the late 2020s through the 2030s. Now that we are in astronomical debt, it's our responsibility to turn our nation into a wasteland in order to provide this particular nation a scalable, full spectrum and robust AI defense solution that will allow them to achieve their geopolitical goals safely without fear of reprisal while they continue to expand their influence in tech and the global economy, hopefully culminating in extracting taxes on ships going through key trade canals near their borders and beyond.
like everything else with the current US administration
they deregulated nuclear safety
* https://www.npr.org/2026/01/28/nx-s1-5677187/nuclear-safety-...
* https://www.npr.org/2026/08/27/nx-s1-5920368/nrc-nuclear-rad...
any other administration even Republican I'd be willing to listen to why
this administration will happily kill thousands or give them cancer if it means another million dollars in their pockets
there is only one kind of nuclear reactor that should be built anymore
and that is Thorium reactors, they "fail safe" (or at least safer)
* https://www.youtube.com/watch?v=ElulEJruhRQ
Probably didn't help that many of those keeping quiet had obvious short-term interests in promoting "nuclear everything". Even as various accidents, leaking waste dumps, and regular warnings of deadly communist mushroom clouds made it damned obvious to the general public that they were being systematically lied to.
Sadly, the pro-nuclear camp is still far too influenced by utopian and partisan considerations.
Yes, it'd be nice to see competently-done SMR's in regular use, for the use cases where they make sense. But if I was a policy maker with finite political capital and resources, I'd probably be winding down nuclear power - both to show the public that I wasn't too gullible to trust, and to show advocates for other technologies that lies and delusions would be carry harsh penalties.
The promise here is the rich fleecing the average citizen.
Getting downvoted wicked hard super fast. But how else are we supposed to see this? How else do we citizens of the world interpret this? The fuel efficiency is a fact. The nuclear clean up has been a problem every single time.
A fully nuclear world needs to use nuclear fuel efficiently, which means breeder reactors.