This is a passionate team working on a very hard problem. They have guts and skills. I've always loved microreactors for fringe remote power where people are willing to pay 20x more than normal diesel generator prices. Like Antarctica, remote bases, the moon etc.
Trying to make microreactors cheap is super hard. We've obviously tried it many times, the most relevant being the truck-mounted military microreactor ML-1 (the only closed-cycle direct gas turbine reactor ever operated) https://en.wikipedia.org/wiki/ML-1.
Shielding is hard. Even a small reactor this size needs like 8 ft. of high density concrete on all sides, or equivalent, plus 4-6" of a heavy metal like tungsten to take down the gammas. You can't just put it underground because the neutrons activate the dirt. Driving it off afterwards is borderline impossible because you generally have to put the spent fuel in robust canisters that can handle collisions, rollovers, and RPG attacks.
But the hardest part is fuel cost. This reactor uses medium-enriched ('HALEU') fuel, which is super expensive, and then it packages it into TRISO form, which is about 100x more expensive to fabricate than regular UO₂ fuel. On the plus side, it's super robust and can minimize the need for other safety systems. Those prices could both go down, conceivably, but the fab process is pretty intricate, and it's hard to bring down enrichment costs. In my analysis, the fuel cost alone nearly makes this kind of reactor uncompetitive with a diesel generator in almost all applications. So even if the reactor is free (because you build it on an assembly line?), you're still out of luck.
Then there's thermal strain. When you're a small reactor you have big gradients. This bends things. Neutrons make it worse. Then you have a tiny box with electronics in it getting absolutely hammered by neutron dose. That does bad things too.
I hope they can find a way to bring fuel costs way down. I really like the people at this company, and I really like nuclear power and want to see it used in many new applications. I just don't quite see the path yet.
Wonder if much of the world didn't turn away from nuclear power they way they did since the 1960s, if we wouldn't have solved alot of problems like these already given research was stagnant (relative to other research in power generation) for a very very long time.
It'd be a much different field if we had kept it up. I spend a lot of time in nuclear archival material, and facilities like CANEL in Middletown CT absolutely blow my mind. They had hundreds of people working on crazy reactor technologies. They were flowing white-hot lithium metal at 100 mph. But yeah we gave all that up. My friend wrote a pretty good article about this not long ago https://www.ans.org/news/2025-05-08/article-6961/hightempera...
If they radiation shield it properly, I'd like to think so. That won't do anything to 8 ft of concrete plus 4" of tungsten.
Plus the fuel form holds in a lot of the fission products even when scattered around. It may overheat and release volatile fission products but I don't think it would be a widespread disaster no matter what.
And you can just remove the control rods and wait for it to melt on its own (meltdown-proof fuel isn't actually, well, proof). You'll get a nice contamination with volatiles (cesium and iodine), for the bonus points you can wait until the end of the fuel campaign to maximize the amount of transuranics.
I just don't think this is a viable option, except for very niche scenarios.
Not really. You have to stop neutrons and gammas. Concrete does neutrons but not gammas, tungsten does gammas but not neutrons.
You can also use water on neutrons or lead on gammas. There are many combos and composites.
Oh and neutrons cause more gammas when they get absorbed. Sometimes there are repeated layers, 3 or 4 times. If you have even tiny impurities in your shield you can get huge unexpected capture gammas
It's a rich tradition for reactors to start out with too little shielding though. Like the Japanese nuclear powered cargo ship Mutsu fired up for the first time, realized they didn't shield well enough, and spent 4 years fixing/retrofitting more shielding.
People are looking into it, but I don't think there's all that much promise. Fine structure of shielding doesn't really matter to an energetic particle that's blowing through meters of it.
Gamma rays are stopped by electron density. Electron density requires high mass density heavy (high Z) nuclides.
Neutrons are stopped by light nuclei via conservation of momentum, and by neutron absorbing nuclei like boron.
If metamaterials can be made with higher density electrons in a way that's cheaper than lead and high hydrogen density that's cheaper than concrete, paraffin wax, or water, then I guess it could be interesting.
I used to work on novel shielding designs. There's some pretty interesting stuff out there but in the vast majority of situations it is just cheaper and easier to pour more concrete.
To add to acidburn's comment, material choice is also highly dependent on the energy levels and particle types. At high energies you basically just maximize mass. At lower energies (more typical for reactors) you can start taking advantage of atomic cross-sections and electromagnetism. That's why they like borated concrete, high neutron cross-section, but only really effective for "thermal neutrons".
I don't really get the "make it small enough to fit on a truck" thing. The main impediment for nuclear is cost, and then being able to build reactors on an assembly line would be a significant advantage. But how much of that advantage is retained if the product comes on more than one truck and the thing that comes is the reactor, the fuel and the turbines whereas the concrete gets poured on-site? It seems like that should get you nearly all of the cost savings from mass production but then you get a full-sized reactor that can power a city instead of something that can only replace a diesel generator.
I think you're missing some use cases and some parameters.
For the average home, this doesn't make sense. But for a hospital? A data center? There are plenty of places that are happy to pay a premium for an independent, redundant, and/or emergency power source. Somewhere like a hospital is going to get big advantages from something like this because it not only provides electricity but hot water (reducing the electrical demand that would go to hot water creation).
There are also big advantages to remote places. Getting power in Alaska[0]. It's even difficult to get it in places like Alberta or Montana, both of which will also would take advantage of the heat source.
Even at 5 years, this is more reliable than something like a gas generator and has a lot of logistical advantages. This says it does 1MW or electric power and 1.9MW of thermal. I found a 1MW generator[1], and it looks to consume between 77-87 gal/hr. A gallon weighs 7lbs, so 80 gal is 560lbs and takes 0.3m3. At one day's consumption (1920 gal) you need to be able to store over 13klbs and it'll take up 7.3m3 (not including the volume of the container and that it needs to be stored somewhere that is dry but also well ventilated). On top of that, diesel has a self life of 6mo (can extend to a year), so you're going to be doing a lot of deliveries...
Given that, I can see a lot of places that would gladly make those trade-offs.
Also, if it can fit self-contained in a container, the parts are going to be much smaller. You gotta start somewhere, right? Doesn't seem a bad idea to start with edge customers who are willing to pay a premium.
> But for a hospital? A data center? There are plenty of places that are happy to pay a premium for an independent, redundant, and/or emergency power source.
Those places are just going to keep a diesel generator, because they only need it once or twice a year and it costs less.
> Somewhere like a hospital is going to get big advantages from something like this because it not only provides electricity but hot water (reducing the electrical demand that would go to hot water creation).
Diesel generators can do the same thing. Meanwhile on ordinary days the power would be supplied from the grid, which is even cheaper than diesel generators.
> There are also big advantages to remote places. Getting power in Alaska
But how many people need a MW of continuous power in the wilderness and are willing to pay that much for it?
The major industry in those areas is oil and gas.
> I found a 1MW generator[1], and it looks to consume between 77-87 gal/hr.
Diesel generators are typically used for emergency power and then the fuel consumption isn't a major concern because they're infrequently used.
Power plants for continuous stationary use will typically use the same generation methods as the grid and can then attach to natural gas pipelines or use generation methods like wind/solar/hydro that don't consume fuel.
For transient use you'd need to move fuel, but in the alternative you have to move the reactor.
> Doesn't seem a bad idea to start with edge customers who are willing to pay a premium.
Sure, but who actually are they? What usage needs a MW of continuous power but has to be in a place that can't connect to the grid? Remote mining operations maybe? But their equipment is designed to run directly on liquid fuels because electricity is assumed to be unavailable.
It's not impossible that it exists but it doesn't seem like a huge market.
Sure, maybe a hospital is not the best example, but it's just serving as a way to see how it is useful. Was just a stand in for something relatable where it was understood how much someone would be willing to pay for a backup. But I'll get to better examples in a second.
> Diesel generators are typically used for emergency power
Yes, but you aren't comparing the cost of storing and delivering diesel. Yes, grid power will be cheaper but is that difference than the costs of storing, transporting, and the need to constantly check? Is it cheaper than the handover time? The time lost when electricity is down. Can you smoothly hand over generation? Is it cheaper than the cost of the gas having spoiled? These mistakes happen and they can be quite costly when it does.
> but it doesn't seem like a huge market.
It definitely is not a huge market. That's why there's a premium. But there are people that need and will pay for it.
I'm also willing to bet you're significantly underestimating how many remote locations there are.
Let's test ourselves. (I got the answer wrong btw and I'm willing to bet most people do.) How many research stations are there in Antarctica? Make a guess first. Here's the answer and a link[0]. And here's for the Arctic[1] (there's more!). These don't even include secret sites! Hell, I'm sure there's even a few towns in Norway[2,3] and Alaska[4], or elsewhere[5] that would be lifetime customers. 1MW isn't close to enough power to supply some of those cities but I would be surprised if they didn't want a highly reliable 1MW source of power and 2MW of heat and weren't willing to pay a high price for it. That energy goes a long way in emergencies.
You're right that many of these locations have oil and gas as major industries but you are not considering two factors. 1) That still needs to be processed. You can't use oil or gas in their raw form (okay, sometimes gas but it still may contain contaminants that need to be separated). 2) You're eating your own supply. It's a lot easier to just export everything than to portion everything out. This is especially true when the product expires. If you don't rely on your own export then you never have to make the choice between "do I have enough for myself" when the product is in high demand elsewhere.
Things like this have extremely high demand for military sites. They'll pay way more to not have to have constant deliveries. We're not even just talking places like nuclear launch sites. There's hundreds of remote listening locations. There's plenty of places that you add one of these to and they could run completely automated.
If we're talking about a really remote location (there are quite a lot of these) then which is cheaper? Once every 5 years helicopter delivery or a constant delivery every 6 mo by truck? That first option could be a lot cheaper. You don't even need to even make a road! Certainly one of these options is much faster.
Again, you're right, in that this isn't a technology we're going to see everywhere (especially at a high price point). But that's a very different thing than "there's no point in building this". I'm just trying to answer the latter question because that's what you put into question. I'm still willing to bet there's a bigger market for this kind of stuff than you would think.
And to be clear, I don't think you're dumb or unimaginative or anything. I see you around here a lot, so I know you're smart. I just think with something like this it's a "everything is an edge case" type of situation, where it is very hard to actually get a good picture. First order approximations won't get you anywhere near the right answer. They're really hard to guesstimate without some expertise. I only know some surface level because I did some work with nuclear tech and we had to find applications. But what I know is that there's a lot of situations I'm not even aware of because even though they are edge cases we're talking about edge cases on the scale of billions. Even serving just 0.00001% of that is probably more than enough to warrant a product like this and make a profit.
[0] Wiki lists 44 permanently active stations and and 45 summer only ones. There's a map below the listing. I was at least 50% off on my estimate. I thought at most there would be 2 dozen. https://en.wikipedia.org/wiki/Research_stations_in_Antarctic...
I have a hard time seeing how communities that have trouble keeping the skills necessary to operate diesel generators will be able to switch to nuclear reactors.
Extracting uranium from seawater gives you natural uranium, which needs to be enriched for use in most power reactors. The reactor under discussion here needs higher uranium enrichment and more expensive fuel fabrication operations than common power reactors. Developing uranium extraction from seawater is a good long-term insurance plan for uranium availability, but it's not going to help this reactor get its fuel costs down.
Pro tip: if you want to check if a nuclear reactor design is vaporware or has real legs, you check their application with the NRC (nuclear regulatory commission). It turns out that the NRC does have a page for Kaleidos [1]. You can even go and see what documents Kaleidos submitted this month. They submitted a request to be exempted from some regulation called "10 CFR 55", which they feel is not applicable to them. I have no clue if that is the case or not, but at least they seem to be in fairly frequent contact with the NRC, and that's good news.
I'm skeptical, not because it can't be achieved, but because it's not that practical.
Diesel generators are "great" because diesel doesn't evaporate. You can have it there for years, and with good design, it just springs up the next day.
This nuclear reactor has to be connected for fleet monitoring if you want to operate it. Which excludes it from many real life scenarios where diesel generators are used.
Maybe for remote locations where constant power is needed (Antarctica and such), but I see their uses being very limited.
> Diesel generators are "great" because diesel doesn't evaporate.
LOL, no. I see, you have never worked with large diesels meant for backup.
If you just leave diesel fuel alone, then over time (6-9 months) the residual water separates at the bottom of the tank. And then various microbial life springs into action, happily living off all of that free energy. While there's some dissolved oxygen, it will happily use it to oxidize the fuel. But even without oxygen, the bugs will try to live off energy produced by polymerization of unsaturated hydrocarbons.
Polymerization == gunk that clogs up your fuel filters.
So you have to periodically clean up diesel fuel by removing water and filtering the gunk out. It's called "fuel polishing". Large diesels will have fixed systems, for smaller diesels, sometimes mobile systems are used like these: https://fueltecsystems.com/equipment/pneumatic-systems-2/
If I Google "diesel shelf life", the most common answer is 12 months. Do you have a better source? Propane probably makes more sense for fuel that needs to sit around for years.
Do you know the shelf life of TRISO fuel? I imagine it doesn't matter because it would be very expensive to build a reactor and not switch it on.
Diesel will degrade with exposure to oxygen, but a diesel engine can burn pretty much any flammable liquid that you can meter out. It really comes down to the engine itself and if it can handle less-than-perfect fuel.
Not sure it will sound as nice though. In fact I don't think I have heard the sound of a runaway nuclear reactor. Maybe due to the turbines it can sound exciting?
Anecdotally, I came across a large (for a single user) quantity of diesel 9 years ago. (Nothing exotic - a company went titsup and I was the only one both bidding for and capable of removing the diesel from their premises within an acceptable time frame; I got approx 80% off the pump price at the time.)
I still run my tractor and Land Cruiser off the stuff; the tractor had an outing today. Granted, neither of those engines are very particular about the fuel they are given, but still...
(Water drained off every few months, also a biocide is added to keep the diesel gunk at bay.)
I mean if you trying to run that fuel in a performance application where you are pushing the fuel to its absolute limit, it might be bad, but most diesel engines can be run on nearly any burnable oil, you just get less power out and a bit dirtier burn.
They give similar specs ideals about gasoline fuel going bad in 3-6 months, and yet 95% of gasoline engines will still run 2 year old fuel fine because they aren't pushing compression ratios to the absolute possible limit, and half of the performance engines that do push limits these days have adaptable computer controlled compression and sensors which will figure out how much it can push the fuel.
If I put 5 year old diesel fuel into any regular diesel motor or generator or vehicle and it didn't start up, I would be extremely surprised, and be most worried that the fuel either wasn't diesel fuel to start with or had a wide open hole in the container that a bunch of rain water drained down into.
That said, if I had some kind of tuned up diesel motor that I was trying to push 800+ HP out of, I probably wouldn't use year old diesel fuel just in case. High performance motors like that are already straddling the line between working great and catastrophic failure and using old potentially bad fuel only adds to it.
> This nuclear reactor has to be connected for fleet monitoring if you want to operate it. Which excludes it from many real life scenarios where diesel generators are used.
I don't understand this sentence, why does connection to fleet monitoring preclude using this microreactor as opposed to a diesel generator? Can't you just hook a starlink up to it, and program it to shut down in the event of prolonged comms loss?
I don't have any first hand experience with diesel generators, but I saw three cases where power was lost and diesel backup was switched on. In two of these three cases, the generator failed (once didn't start, the other time it ran for 30 mins). In both cases it was in scenarios where I'd imagine reasonable care and maintenance were applied.
Am I right that 1MW of solar generation would only take about a football field worth of panels? Of course that doesn't account for battery or other storage for nighttime, etc. but seems like it would be far cheaper and far less regulatory issues unless you really needed that much power generation in a very small footprint.
Looks like a giant part of the value is that it can be shipped in, dropped on the ground on site, turned on overnight, and it only takes up the footprint of a shipping container.
If you have 24 hrs to find an empty football field within a powercable's distance of what you're trying to power, and then fill it with solar panels and batteries, you're gonna have a bad day.
If you ship in a stack of panels, inverters and cables, sure. But maybe you could be a little smarter about it, like a container with all the electronics (inverters, batteries, management) and a bunch of folded, pre-cabled panels that you can pull out across a field. If you bring a couple of those covering a field in a few hours shouldn't be that hard and could be ready for use instantly provided the batteries are charged at delivery.
You also have to make sure there's an empty football field onsite. That's a much harder ask than dropping a shipping container in a couple of parking spots.
Not sure if you’re serious. Is this something you’re proposing be used in an urban environment?
Using a bomb to flatten the nearby trees/debris/buildings/people to make way for solar panels strikes me as not preferable to a clean standalone box providing a MW of power for 5 years at a time.
Also the environment would thank you for choosing nuclear over this.
Blowing up the home of birds and countless other species, yeah ok. Blowing up the the home of humans that can be warned and evacuated effectively, you must be kidding right!?!
I get that you don't like the idea in general, no matter who it is dropped on, but take a step back and examine your reaction.
There are plenty of examples of things that are not equal like skin color or gender and yet we - I assume you are not racist or sexist - try to treat equal. Drawing a hard line in the sand at human and everything else seems well ... really an Orangutan and a Human are so different that they deserve completely different rights, what about whales that have languages likely as complex or more complex than humans? Don't get me wrong I don't believe a cricket has the same emotional reasoning capabilities as a human. But it strikes me as very human to define in-groups people like you and people or beings other than you and using that as justification to do horrible things to them.
First of all, you've created a strawman out of what you assume I believe.
> But it strikes me as very human to define in-groups people like you and people or beings other than you and using that as justification to do horrible things to them.
This is a behavior nonspecific to humans...not sure if you've heard of it, but there's this fascinating emergent behavior among wild animals that naturalists have occasionally observed - in colloquial terms, they've labeled it "predator and prey".
Comparing the industrialized usage of animals like pigs and cows to "predator and prey" is not a good comparison in my opinion. For the record I'm totally fine with indigenous humans hunting and killing animals. The scale and industrialized nature is what makes a big difference I find, the same way killing someone in self defense and genocide both involve the murder of humans, yet there is a qualitative difference I wouldn't ignore.
Many predatory species engage in behavior that limits their hunting to avoid making their prey extinct. Right now extinction rates are >1000x above the baseline a couple hundred years ago. What we are doing to the biosphere we are currently part of is short sighted self sabotage - which is in large parts fueled by a wide spread human supremacist mindset.
What urban environment? Isn't this about to be able being deployed somewhere way out there? Where diesel is impractical because of logistics? In which urban environment that would be the case? And wouldn't that environment have to be flattened, torn down, and rebuilt to be economically viable again, anyway?
Are you're seriously comparing a few containers of fold-out solar panels and batteries to a portable nuclear reactor?
Let's do the math: To match even a 1MW reactor, you'd need 2,000+ panels, inverters, batteries, mounting, and approx. 120-150 man-days of labor...and that's with pre-cabled gear. You're still looking at 8+ containers, a full crew, and a full 10-14 days to deploy, not "a few hours."
A nuclear microreactor doesn't need 54,000sqft of land or weather-dependent storage. Nice idea for a solar camp but not a replacement for a compact nuclear source.
Let’s not pretend to be offended that someone else is making up an unfair scenario, as if you guys didn’t already make one up.
Nobody’s dropping off a nuclear fucking reactor in the middle of a disaster area on six hours’ notice in any universe other than the bizarro one invented by their PR firm.
You’re maybe running water desalination for an island that has known for years they want an alternative to shipping in diesel, or you’re shipping diesel generators to a disaster area because the Red Cross has a stack of them in a warehouse ready to go.
Or you’re some hyperscaler data center hoping to not have to maintain fifteen generators onsite for you eight server rooms (8 + 4 + 2 + 1 = 15), and those could potentially be replaced with battery systems or gas turbines. And again, on six months or more of notice.
If someone had an easy non-snake-oil nuclear solution we would be using it already. A realistic person would assume incremental improvements in portable nuclear over the next twenty years, not an overnight success.
> If someone had an easy non-snake-oil nuclear solution we would be using it already.
Nuclear has been pretty much regulated to death. This is definitely not true.
> Nobody’s dropping off a nuclear fucking reactor in the middle of a disaster area on six hours’ notice in any universe other than the bizarro one invented by their PR firm.
Why not? It absolutely has the potential to be cheap, reliable and safe. That sounds like a fantastic use case. The biggest reason we don't do that is environmental lobbying regulating the technology into oblivion.
I grew up an hour from a lake you couldn’t swim in because the cooling equipment for the plant caused microbes to grow that cause encephalitis. Those regulations are written in blood and you’re fantasizing about an unattended reactor as the next generation? No. Dream on.
I’m not saying it’ll never happen. I’m saying the work hasn’t been done and this is more snake oil.
And then there’s the physics and logistics the other responder mentioned. For conventional reactors, that much concrete of a very specific and difficult quality to achieve in that many layers is expensive. The last one I heard about being built they had to jackhammer off many feet of the base because they missed spec, and lay it all over again. And the carbon footprint of that much concrete is not tiny. The embodied cost of a built plant is huge, and repairs are constant. They aren’t free, even if you ignore heat pollution, and we are running out of runway for that conceit.
FAA regulations are written in blood, too - and yet our private aircraft technology is ancient (and likely less safe than modern tech could facilitate) because those same regulations make the cost to innovate astronomical. I would not make the mistake of believing that regulations do more than freeze our tech in a relatively safe local minima.
You're describing the engineering problems of rarely-produced machinery, and seem to imagine that we can't figure out how to do that better, and cheaply, at scale? The potential market for a shipping-container-sized MW-scale power supply is likely huge.
I'm not comparing anything, I'm just saying a solar solution doesn't have to be discounted because of my OP's incredulity about deployment characteristics. No need for hostility.
And it's closer to 4-6x football fields if you did it in say, San Francisco. 4-5x football fields in Kansas City. 6-8x football fields in Chicago. Again, plus battery storage.
Not many, it’d be roughly 1MWH of storage, based on looking at battery storage in half size conexes that are currently available for sale. A 1MW reactor or diesel genset can put out 1MWH every single hour for as long as they have fuel.
I was able to find some that were a bit over 3.1 MWH.
It is unlikely that those 1) cost as much as a nuclear reactor or 2) are exactly the amount of available space you have. So 2 or 3 aren’t going to solve your water desalination problems but might solve your intermittent power ones.
Just FYI, every building that is required by law to have emergency backup power has an engine-generator set. There are zero exceptions to this rule. If batteries were able to serve critical loads like hospitals and emergency dispatch centers, they would be allowed to be installed for that purpose, but they aren’t. This should end the argument about battery backup, at least until battery storage density reaches a point where it can serve those loads.
To add, grid-scale batteries do make sense if you have a ton of cheap land. Most facilities that need backup power aren’t in areas with lots of cheap available land for battery installations.
The kind of backup power needs that hospitals, data centers, and other critical facilities have (multiple MWH per hour at minimum for large facilities) and the durations they need to operate for, combined with the land prices in the areas where they are situated, make battery backup for critical power needs uneconomical due to the space needed with current battery energy density.
That’s not half the size of a flatbed trailer and nobody with space for one trailer has real problems to solve that can be solved with a single delivery.
It’s cargo container size and that’s apparently a few MWH of battery these days.
It depends on where you're at, but for a sunny place yes; somewhere like London a panel can harvest ~100 W/m^2 (0.5 MW for a football field with 100% panel coverage) averaged over the whole year, while in Arizona it's more like 230 W/m^2 (1.2 MW for a football field). NREL has some great insolation maps here: https://www.nrel.gov/gis/solar-resource-maps
For a permanent installation I would agree that solar would usually make more sense, but the mini reactor might be better in scenarios where it's replacing a diesel generator - emergencies, temporary events, confined spaces, etc.
It requires space, setup time, and then there's the intermittency issues. You'd need enough batteries to store, what, 12 MWh? 20? More if you're accounting for cloudy days?
People just want a compact solution to generate power, not a whole separate project.
“Only” a football field is a lot of space. A 1MW diesel genset on a trailer is about 30’ long by 8’ wide by 10’ tall, which is 0.4% of a football field.
That used to be true, not so sure my trust in our institutions is high these days. Seems a few million $ donation to the right people can make all regulations just vanish.
No, that used to be believed to be true. We're just seeing the curtain come down.
The food pyramid, the CIA's "war on drugs" in South America, the wars with Iraq, Libya.. Just to name a few. Why do we pretend like bribery and corruption is this new thing?
Here's a related company, Ultra Safe Nuclear, making TRISO fuel units.[1]
They went bankrupt in April 2025.[2] They at least got as far as making fuel units, although I suspect the video shows dummies being made, because they are not taking enough precautions for handling enriched uranium.
I'm not filled with optimism about this concept. Let's work backwards from crash safety (say a reactor on a truck getting t-boned by a freight train). The radioactive material needs to be held in an armored containment to avoid release. That would have to be roughly comparable to CASTOR containers in terms of its resilience. But these containers have limited capability of passive thermal energy dissipation (Google finds models that handle 10kW to 45kW thermal power generated in the interior). This would be approximately the ceiling for the direct thermal power output that is still reduced by limited efficiency of heat-to-power conversion.
This is admittedly napkin math, but it should be good enough to set expectations.
You are thinking accidents. I think we need to be thinking deliberate attempts to compromise these things and all the security measures needed to mitigate against that. And most importantly, the cost associated with that. Which comes on top of already significant cost.
The naive notion of we'll just ship these all over the place by the thousands and it's going to be fine is not going to withstand a lot of critical thinking very long.
I was indeed not thinking about deliberate attacks. But that doesn't change the result much as I assume that the CASTOR containers that I used as reference are designed to withstand all of these worst case scenarios.
Solar already runs circles around nuclear when it comes to cost. Typically combined with batteries. The combination is popular and cost effective.
With nuclear it's all rosy and optimistic. But also almost 100% hypothetical. And the industry has a piss poor record delivering on its promises. 200-300% cost overruns are routine.
We won't see more than a handful small small nuclear reactors for years to come. We might get to hundreds by the 2040s or so. Maybe growing to thousands or even tens of thousands by the 2050s under the optimistic scenario.
Most of these things have the power output of a handful of wind turbines, of which we have close to half a million right now around the world with more coming online all the time. The challenge here is that wind turbines are just stupidly cheap and scalable at this point and still getting better.
SMRs will remain very niche for a long time even if they do get their cost levels under control. Which is a big if. Thousands of these things would barely move the needle in terms of power output. Essentially all of the expected growth in electricity demand for the next few decades is going to be met by wind and solar supported by batteries.
> The plan is for the small amount of spent fuel [..] that comes out of our reactors at the end of their duty cycle to only be temporarily stored on-site until a federal repository or interim storage solution becomes available.
>The NRC is legally required to ensure that, in the event of bankruptcy that the site is secure and the spent fuel remains safely managed before ultimately transferring over to the U.S. Department of Energy's (DOE) possession
So basically like with all other nuclear, the tricky parts with unknown costs are handed over to future taxpayers. These costs are thereby removed from the estimates in Kaleidos business plan making it seem like it's a viable business, which is isn't otherwise.
Meanwhile the founders get rich today, since immense amounts of money has to be presented upfront, before any energy is produced at all.
The obvious replacement for diesel generators today is solar+batteries, which is evident in many countries that used to rely on small scale diesel generators already.
"The plan is for the small amount of spent fuel (the volume of the spent fuel in one reactor is equivalent in size to just two Walmart gas grill propane tanks) that comes out of our reactors at the end of their duty cycle to only be temporarily stored on-site until a federal repository or interim storage solution becomes available. "
> equivalent in size to just two Walmart gas grill propane tanks
Is this a real measurement in tank sizes? Why not just say two 20lb tanks? What if I bought my tank from Home Depot? Are they a different size? Do they think using Walmart makes it more relatable?
I mean that is exactly what we do right now with all nuclear waste. Without a nuclear material repository there is only so much you can do. You don't want to just dig a simple hole somewhere and start tossing everyone's high level waste into it, that would just be asking for a massive disaster.
Could this be associated to a supposed recent State Department approval?
“I just approved a program to deploy small modular nuclear reactors built in the United States to an allied country to help with their sort of energy infrastructure.”
“Which allied country would that be?”
“I can't tell you. It's not public yet.”
From Interesting Times with Ross Douthat: The DOGE Alum Asking if Foreign Aid Is America’s Problem, Jul 31, 2025
Meet EMD DDA40X [1], the most powerful diesel–electric locomotive model ever built on a single frame incorporating two diesel engines with an effective power output of 4920 kW. Given the expected losses in the diesel engines (~40-45% effective, 60-55% waste mostly in the form of heat) and diesel-electric traction system (power generation, traction motors, gearing etc, around 80% effective) which gives a total system efficiency of around 35%. Assuming most of the waste energy ends up as waste heat this ~30m long locomotive (a bit more than two 40ft containers) needs to shed around 9 MW of waste heat or about 4 MW per 40ft standard container length.
1.9 MWt still seems like a huge amount of energy/heat for something that fits on a truck and is supposedly air-cooled (they claim no water is required).
Where does all that heat go?! They must have some very impressive fans.
Heat transfer has the lovely property of scaling nonlinearly by temperature difference. You need a lot of big fans to cool your CPU from 75C on the die to a 25C room, instead of a 50C difference these reactors will dump heat at hundreds of degrees C warmer than the local environment.
Yes, that's crazy. They say up to 1 MW electric which would mean (33% efficiency) 2 MW of heat to get rid of with air cooling. Later they mention facility heating which sounds more realistic, I guess?
You'd be surprised at what the CAD software can do now in 3D renders. You have to design the thing in CAD anyways, so it's not like the 3D team had to model it from scratch. You could probably just do this with a request on Fivr. These aren't your parents 3D prices any more
Everything I've heard is that micro-reactors produce far worse waste situations than larger scale options.
I think there's a huge opportunity for nuclear power in the world today.
But: all these micro-reactor strike me as disastrously bad idea, that's all too likely to offload incredibly complex nasty gross problem to the future. Costs that alas will likely be handled as network externalities, as drains and damage against humanity and people and government, that the creators and purchasers of these device will skate through with comparatively little injury.
Considering that fossil fuels "solve" the problem by literally dumping its waste onto the atmosphere, endangering the global ecosystem, and we're still merrily using them...
I think it's a bit melodramatic to say microreactors offload nasty environmental problem to the future. Also, their environmental problem is literally at the scale of "Drop them in an abandoned mine somewhere, where they cause zero harm to the world, and we will have a few centuries to figure it out."
Recapturing the CO2 from the environment of fossil fuels is almost impossible is almost impossible. Recapturing radionuclides is much much more difficult. Also the duration in which radionuclides are a problem has to be taken into consideration, making even babysitting nuclear waste extremely expensive.
It require enormous care & effort. It's fantastically costly. Do I think it was worth it? For a mission like this: I think yes. For the good of a nation. And a Nation that hopes to still be around to take care of the problem, the complex decomissioning decades latter. But I have so little faith that private interests will endure and bear their own responsibility for this awesome but deeply corrupting irradiating force.
This was new to me so I looked it up- "MWt" means Megawatts Thermal - e.g. the heat output of a reactor, which would be turned into a smaller value of MWe- Megawatts Electric
Yep. And the Russians have had pluggable nuclear power for years now.. on barges: wikipedia.org/wiki/Akademik_Lomonosov
Decommissioning no doubt will consist of scuttling them over a trench. Definitely going to wake the Kraken.
The nukes on a carrier are a much smaller team within the carrier's full crew though. So if you extracted the guys that glow in the dark, it might be more inline
Meh it's a little bit worse, because smaller reactors burn a smaller fraction of their fuel and therefore make more volume of high level waste per kWh generated.
But it's not THAT much worse. Nuclear waste is already ridiculously small in volume per kWh vs. any other fuel-burning energy technology. Right now all of the waste we've accumulated from making 20% of the country's electricity for decades fits on a football field 3 meters high (that's pellets only, if you include individual dry casks it's 135 meters). So if we make lots of small reactors that are a bit less fuel efficient we might need 2 big football fields deep underground rather than 1. Compared to all the particulate and CO₂ emissions other sources make I'm just not that worried about it. Recall that fossil kills ~6 million per year from particulate emissions alone. Commercial nuclear waste has never hurt anyone, and is unlikely to do so in the future.
If interstellar travel ever becomes possible you'd already have access to all the resources of the solar system as well as the output of the entire sun.
The scale of the problem l, technologically simply renders earthbound resource constraints irrelevant.
Like you're into "synthesize antimatter with solar power" at that point.
> If interstellar travel ever becomes possible you'd already have access to all the resources of the solar system as well as the output of the entire sun.
I'm not going to argue circular conditions, this is precisely why we should preserve dense energy sources, first an alternative abundant energy source must be demonstrated, before squandering it locally.
> The scale of the problem l, technologically simply renders earthbound resource constraints irrelevant.
Hidden in such statements is the implicit assumption that mining the solar system for fissile materials is less energy intensive than mining them locally.
We should make sure interstellar travel remains affordable by the time we decide to afford seeding other star systems.
Nothing prevents interstellar travel with current technology, it would just take a long time. We should keep this mode of travel, where survival on the ship is powered with known feasible technology (nuclear fission) on the table and conserve fissile materials until we succeed in compact fusion plants, in that case this constraint no longer is an argument to preserve fissile materials.
Speculating other energy storage technology like "antimatter storage as a battery to store solar power" before launching to another star is just that: speculation. We shouldn't squander fissile materials on the basis of feel-good speculation.
No the assumption is that the magnitude of energy involved in interstellar travel is so large that it dwarfs all other considerations. If you can't afford to expend the energy to travel around the solar system to acquire resources, you definitely can't afford to engage in interstellar travel.
And then of course, if you can't afford the energy to sustain a human population on Earth in decent conditions, you also definitely can't afford interstellar travel. Because implicit in your assumption is that somehow the extremely limited number of people who could be put on a slow ship (and by slow we're talking thousands of actual years minimum at "current technology" levels) will somehow be able to command and control all of Earth's fissile resources.
Interstellar travel to… where? It’s like saving your money for an immortality treatment that’ll eventually hit the market. Well yes it might, someday in the far far future. Practically speaking, this money should better be invested in your health now instead, aka. preservation of the only spaceship we have right now—Earth.
Short of discovering portals or wormholes (natural or artificial), we should only assume demonstrated space propulsion technology to make the trip. With current technology its a long trip, and its cold and dark inbetween 2 stars. We should definitely conserve fissile materials until we demonstrate fusible materials for reliable power generation.
The USSR did it first! No, really. There was a mobile power plant: Pamir-630D ( https://imgur.com/a/rCexHAA ).
It was even deployed to provide power to a remote Arctic outpost. It had to use an exotic coolant (basically, a rocket oxidizer) to make it work, and it had to be placed far away from anything else. The shielding was not enough to bring down the gamma radiation to a safe level when the reactor was active.
Not sure about who was first but McMurdo station in Antarctica was for a time powered by a nuclear reactor almost identical in power to the one being discussed here: http://large.stanford.edu/courses/2014/ph241/reid2/
Neat, I never heard of that! Im surprised there isn't even an english wiki page for it, I had to translate russian wikipedia and even that was a bit limited in information to satisfy my curiosity so ill have to look at other sources.
I actually was mistaken. The photo is from an earlier project: TES-3, from 1960. It was a system with 4 mobile units and a reactor that needed to be buried for shielding.
* no pictures even of prototypes just computer graphics.
* helium is notoriously hard to keep from leaking
* it's all just way too promising and convenient and appealing. Who doesn't want a reactor that fits in a shipping container? Who doesn't want reliable, clean energy? Who doesn't like hospitals and the military? Does it also release puppies and cure cancer?
Looks aspirational to me. 1Mw electricity at 30-100% efficiency (100??) and 1.9 Mw heat via air in the volume of a shipping container? That's moving a lot of air. And I'd want fail safe, passive control "rods" (what happens if the helium leaks out and the heat isn't being removed) before I'd sleep easy with one in my back yard.
>We have fully modeled worst-case - as well as lesser-case - scenarios for an accident or leak. The analysis has shown zero impact experienced by the public.
A flame chart of energy consumption to customer from well-head typically shows an astronomical amount consumed at head in the gas train. It can be a significant sub of the total available energy consumed at the head and in pipeline and shipping, to produce the output which can be sold.
Unfortunately much of it can't be sold or shipped off site and if it isn't used, will be fugitive gas emissions or flared.
Replacing the diesel and other fuels used on-site is good. But it's only part of the story. Running the train would certainly burn a lot of gas, so replacing that would be good.
(-not a fan of SMR for a variety of reasons, mostly political)
I have no idea if the testing will go well, if the regulatory/political environment will accept it, but as far as the company, the tech and the promise of testing?
I would imagine refuelings are limited because at some point you are going to need to inspect and potentially replace some of the critical components that have been exposed to hard radiation. Materials that we would think of as stable can degrade in such high radiation environments. Like a large chunk of steel can have its crystal structure disrupted as atoms get displaced by high energy neutron strikes or other fission fragments, changing its material properties and making it weaker or in most cases more brittle. Localized impurities can also be formed by either alloying elements in the metal being displaced the same way, or from transmutation of atoms into other elements from the strong radiation. And along with disrupting the material strength those impurities can cause hot spots in the metal causing more stresses and fatigue and further reducing it's lifespan.
We are actually pretty good at making alloys and materials today that can resist radiation problems better and more predictably these days, but there is still a bit of randomness from manufacturing variables that means you need a pretty large safety margin to prevent problems. They probably would work for a dozen refuelings, but the consequences of a reactor breech are too high to not have a massive safety margin. And maybe after they ran these for a few refuelings and inspected enough of them they could bump up the refueling limit before inspection or replacement a little.
> 3. Is it really safe to fly around with in an airplane? Can major airlines help distribute these via standard flight routes to reduce cost?
These are too big for your standard air freight network or aircraft (that is, it's significantly larger then any typical ULD [Unit Load Device, shipping containers for airplanes]).
So it'll definitely be a charter to get one delivered. Weights going to be the big determinant in cost, dimensionally it looks like you could get it into anything bigger then a C-130. I doubt you'll be within the C-130s weight limits though.
Not a bad idea. But what if we scaled it up, say to 1.0GW. It wouldn't be portable, but it would sure be useful. So of course we instead take the fuel to the reactor. We could even call it a nuclear plant, because it doesn't move. Can we do that instead?
Looks basically like the TRIGA reactor design (without the water shielding). Seems to have similar challenges with rapid load changes. At one time I thought NASA was looking at something like this tied together with a battery pack that would allow for rapid changes in dynamic load without a lot of stress on powering up/down the reactor. And now I can't find it. Sigh.
If you're a billionaire building your bunker this would be the ultimate off-grid power source :-).
It's a lot different from a TRIGA. It doesn't have hydrogen in the fuel and it uses high temperature/high pressure helium gas as the coolant (vs. water in a TRIGA).
We did run a nuclear reactor in space once that did use TRIGA fuel. It was called SNAP-10A. More recently, the Kilopower test ran a reactor on land but intended for space with a U-Mo metallic fuel.
I'm sure there's a few catches or weed already have them back ordered globally but frankly anything that normalises using these self heating rocks to boil water gets my vote :)
I know that this is a joke, but reactors cannot scale down that far. Unlike an electrical source powered by radioactive decay (like certain pacemakers [1]), the minimum mass for a nuclear reactor includes several kilograms of material. It's possible to shed neutron moderator mass by using high-purity fuel operating on fast fission, but these require more fuel to go critical so they still have multi-kilogram masses.
Bottom line: nuclear waste is forever while their promises are a fart in the wind. If they find any rules or regulations or judgements from any courts to be inconvenient they need only shove some cash up Trump's ass and then, POOF! all their problems are solved... except that, yeah, the waste will still be there. Oh, well - somebody else's problem. MAGA!
Yes it's real. There are a lot of good people who I know personally and a lot of funding going into this. They have a plan to get fuel and will try to turn the first one on in Idaho soonish (like next year)
This is a passionate team working on a very hard problem. They have guts and skills. I've always loved microreactors for fringe remote power where people are willing to pay 20x more than normal diesel generator prices. Like Antarctica, remote bases, the moon etc.
Trying to make microreactors cheap is super hard. We've obviously tried it many times, the most relevant being the truck-mounted military microreactor ML-1 (the only closed-cycle direct gas turbine reactor ever operated) https://en.wikipedia.org/wiki/ML-1.
Shielding is hard. Even a small reactor this size needs like 8 ft. of high density concrete on all sides, or equivalent, plus 4-6" of a heavy metal like tungsten to take down the gammas. You can't just put it underground because the neutrons activate the dirt. Driving it off afterwards is borderline impossible because you generally have to put the spent fuel in robust canisters that can handle collisions, rollovers, and RPG attacks.
But the hardest part is fuel cost. This reactor uses medium-enriched ('HALEU') fuel, which is super expensive, and then it packages it into TRISO form, which is about 100x more expensive to fabricate than regular UO₂ fuel. On the plus side, it's super robust and can minimize the need for other safety systems. Those prices could both go down, conceivably, but the fab process is pretty intricate, and it's hard to bring down enrichment costs. In my analysis, the fuel cost alone nearly makes this kind of reactor uncompetitive with a diesel generator in almost all applications. So even if the reactor is free (because you build it on an assembly line?), you're still out of luck.
Then there's thermal strain. When you're a small reactor you have big gradients. This bends things. Neutrons make it worse. Then you have a tiny box with electronics in it getting absolutely hammered by neutron dose. That does bad things too.
I hope they can find a way to bring fuel costs way down. I really like the people at this company, and I really like nuclear power and want to see it used in many new applications. I just don't quite see the path yet.
Wonder if much of the world didn't turn away from nuclear power they way they did since the 1960s, if we wouldn't have solved alot of problems like these already given research was stagnant (relative to other research in power generation) for a very very long time.
It'd be a much different field if we had kept it up. I spend a lot of time in nuclear archival material, and facilities like CANEL in Middletown CT absolutely blow my mind. They had hundreds of people working on crazy reactor technologies. They were flowing white-hot lithium metal at 100 mph. But yeah we gave all that up. My friend wrote a pretty good article about this not long ago https://www.ans.org/news/2025-05-08/article-6961/hightempera...
In order for this to happen, making websites and mobile apps is going to have to get a lot less lucrative.
> On the plus side, it's super robust and can minimize the need for other safety systems.
Can it survive 20 kilos of TNT planted by a terrorist?
If they radiation shield it properly, I'd like to think so. That won't do anything to 8 ft of concrete plus 4" of tungsten.
Plus the fuel form holds in a lot of the fission products even when scattered around. It may overheat and release volatile fission products but I don't think it would be a widespread disaster no matter what.
Well, how about a 500 kg shaped charge?
And you can just remove the control rods and wait for it to melt on its own (meltdown-proof fuel isn't actually, well, proof). You'll get a nice contamination with volatiles (cesium and iodine), for the bonus points you can wait until the end of the fuel campaign to maximize the amount of transuranics.
I just don't think this is a viable option, except for very niche scenarios.
Could you reduce the amount of concrete by increasing the amount of tungsten?
Not really. You have to stop neutrons and gammas. Concrete does neutrons but not gammas, tungsten does gammas but not neutrons.
You can also use water on neutrons or lead on gammas. There are many combos and composites.
Oh and neutrons cause more gammas when they get absorbed. Sometimes there are repeated layers, 3 or 4 times. If you have even tiny impurities in your shield you can get huge unexpected capture gammas
It's a rich tradition for reactors to start out with too little shielding though. Like the Japanese nuclear powered cargo ship Mutsu fired up for the first time, realized they didn't shield well enough, and spent 4 years fixing/retrofitting more shielding.
Is anybody considering the research into and use of metamaterials for shielding instead? Like 2D-twisted-hyperhexasomething?
People are looking into it, but I don't think there's all that much promise. Fine structure of shielding doesn't really matter to an energetic particle that's blowing through meters of it.
Gamma rays are stopped by electron density. Electron density requires high mass density heavy (high Z) nuclides.
Neutrons are stopped by light nuclei via conservation of momentum, and by neutron absorbing nuclei like boron.
If metamaterials can be made with higher density electrons in a way that's cheaper than lead and high hydrogen density that's cheaper than concrete, paraffin wax, or water, then I guess it could be interesting.
I used to work on novel shielding designs. There's some pretty interesting stuff out there but in the vast majority of situations it is just cheaper and easier to pour more concrete.
To add to acidburn's comment, material choice is also highly dependent on the energy levels and particle types. At high energies you basically just maximize mass. At lower energies (more typical for reactors) you can start taking advantage of atomic cross-sections and electromagnetism. That's why they like borated concrete, high neutron cross-section, but only really effective for "thermal neutrons".
Can a skyscraper?
I don't really get the "make it small enough to fit on a truck" thing. The main impediment for nuclear is cost, and then being able to build reactors on an assembly line would be a significant advantage. But how much of that advantage is retained if the product comes on more than one truck and the thing that comes is the reactor, the fuel and the turbines whereas the concrete gets poured on-site? It seems like that should get you nearly all of the cost savings from mass production but then you get a full-sized reactor that can power a city instead of something that can only replace a diesel generator.
I think you're missing some use cases and some parameters.
For the average home, this doesn't make sense. But for a hospital? A data center? There are plenty of places that are happy to pay a premium for an independent, redundant, and/or emergency power source. Somewhere like a hospital is going to get big advantages from something like this because it not only provides electricity but hot water (reducing the electrical demand that would go to hot water creation).
There are also big advantages to remote places. Getting power in Alaska[0]. It's even difficult to get it in places like Alberta or Montana, both of which will also would take advantage of the heat source.
Even at 5 years, this is more reliable than something like a gas generator and has a lot of logistical advantages. This says it does 1MW or electric power and 1.9MW of thermal. I found a 1MW generator[1], and it looks to consume between 77-87 gal/hr. A gallon weighs 7lbs, so 80 gal is 560lbs and takes 0.3m3. At one day's consumption (1920 gal) you need to be able to store over 13klbs and it'll take up 7.3m3 (not including the volume of the container and that it needs to be stored somewhere that is dry but also well ventilated). On top of that, diesel has a self life of 6mo (can extend to a year), so you're going to be doing a lot of deliveries...
Given that, I can see a lot of places that would gladly make those trade-offs.
Also, if it can fit self-contained in a container, the parts are going to be much smaller. You gotta start somewhere, right? Doesn't seem a bad idea to start with edge customers who are willing to pay a premium.
[0] https://app.electricitymaps.com/zone/US-AK/72h/hourly
[1] https://mart.cummins.com/imagelibrary/data/assetfiles/007036...
> But for a hospital? A data center? There are plenty of places that are happy to pay a premium for an independent, redundant, and/or emergency power source.
Those places are just going to keep a diesel generator, because they only need it once or twice a year and it costs less.
> Somewhere like a hospital is going to get big advantages from something like this because it not only provides electricity but hot water (reducing the electrical demand that would go to hot water creation).
Diesel generators can do the same thing. Meanwhile on ordinary days the power would be supplied from the grid, which is even cheaper than diesel generators.
> There are also big advantages to remote places. Getting power in Alaska
But how many people need a MW of continuous power in the wilderness and are willing to pay that much for it?
The major industry in those areas is oil and gas.
> I found a 1MW generator[1], and it looks to consume between 77-87 gal/hr.
Diesel generators are typically used for emergency power and then the fuel consumption isn't a major concern because they're infrequently used.
Power plants for continuous stationary use will typically use the same generation methods as the grid and can then attach to natural gas pipelines or use generation methods like wind/solar/hydro that don't consume fuel.
For transient use you'd need to move fuel, but in the alternative you have to move the reactor.
> Doesn't seem a bad idea to start with edge customers who are willing to pay a premium.
Sure, but who actually are they? What usage needs a MW of continuous power but has to be in a place that can't connect to the grid? Remote mining operations maybe? But their equipment is designed to run directly on liquid fuels because electricity is assumed to be unavailable.
It's not impossible that it exists but it doesn't seem like a huge market.
Sure, maybe a hospital is not the best example, but it's just serving as a way to see how it is useful. Was just a stand in for something relatable where it was understood how much someone would be willing to pay for a backup. But I'll get to better examples in a second.
Yes, but you aren't comparing the cost of storing and delivering diesel. Yes, grid power will be cheaper but is that difference than the costs of storing, transporting, and the need to constantly check? Is it cheaper than the handover time? The time lost when electricity is down. Can you smoothly hand over generation? Is it cheaper than the cost of the gas having spoiled? These mistakes happen and they can be quite costly when it does. It definitely is not a huge market. That's why there's a premium. But there are people that need and will pay for it.I'm also willing to bet you're significantly underestimating how many remote locations there are.
Let's test ourselves. (I got the answer wrong btw and I'm willing to bet most people do.) How many research stations are there in Antarctica? Make a guess first. Here's the answer and a link[0]. And here's for the Arctic[1] (there's more!). These don't even include secret sites! Hell, I'm sure there's even a few towns in Norway[2,3] and Alaska[4], or elsewhere[5] that would be lifetime customers. 1MW isn't close to enough power to supply some of those cities but I would be surprised if they didn't want a highly reliable 1MW source of power and 2MW of heat and weren't willing to pay a high price for it. That energy goes a long way in emergencies.
You're right that many of these locations have oil and gas as major industries but you are not considering two factors. 1) That still needs to be processed. You can't use oil or gas in their raw form (okay, sometimes gas but it still may contain contaminants that need to be separated). 2) You're eating your own supply. It's a lot easier to just export everything than to portion everything out. This is especially true when the product expires. If you don't rely on your own export then you never have to make the choice between "do I have enough for myself" when the product is in high demand elsewhere.
Things like this have extremely high demand for military sites. They'll pay way more to not have to have constant deliveries. We're not even just talking places like nuclear launch sites. There's hundreds of remote listening locations. There's plenty of places that you add one of these to and they could run completely automated.
If we're talking about a really remote location (there are quite a lot of these) then which is cheaper? Once every 5 years helicopter delivery or a constant delivery every 6 mo by truck? That first option could be a lot cheaper. You don't even need to even make a road! Certainly one of these options is much faster.
Again, you're right, in that this isn't a technology we're going to see everywhere (especially at a high price point). But that's a very different thing than "there's no point in building this". I'm just trying to answer the latter question because that's what you put into question. I'm still willing to bet there's a bigger market for this kind of stuff than you would think.
And to be clear, I don't think you're dumb or unimaginative or anything. I see you around here a lot, so I know you're smart. I just think with something like this it's a "everything is an edge case" type of situation, where it is very hard to actually get a good picture. First order approximations won't get you anywhere near the right answer. They're really hard to guesstimate without some expertise. I only know some surface level because I did some work with nuclear tech and we had to find applications. But what I know is that there's a lot of situations I'm not even aware of because even though they are edge cases we're talking about edge cases on the scale of billions. Even serving just 0.00001% of that is probably more than enough to warrant a product like this and make a profit.
[0] Wiki lists 44 permanently active stations and and 45 summer only ones. There's a map below the listing. I was at least 50% off on my estimate. I thought at most there would be 2 dozen. https://en.wikipedia.org/wiki/Research_stations_in_Antarctic...
[1] There's 57 active stations. https://en.wikipedia.org/wiki/List_of_research_stations_in_t...
[2] https://en.wikipedia.org/wiki/Hammerfest_(town)
[3] https://en.wikipedia.org/wiki/Honningsv%C3%A5g
[4] https://en.wikipedia.org/wiki/Utqiagvik,_Alaska
[5] https://en.wikipedia.org/wiki/List_of_northernmost_settlemen...
I have a hard time seeing how communities that have trouble keeping the skills necessary to operate diesel generators will be able to switch to nuclear reactors.
https://www.spitsbergen-svalbard.com/2024/04/09/longyearbyen...
> I hope they can find a way to bring fuel costs way down.
I've spoke with some researchers and investors working on seawater uranium extraction and left quite optimistic.
Extracting uranium from seawater gives you natural uranium, which needs to be enriched for use in most power reactors. The reactor under discussion here needs higher uranium enrichment and more expensive fuel fabrication operations than common power reactors. Developing uranium extraction from seawater is a good long-term insurance plan for uranium availability, but it's not going to help this reactor get its fuel costs down.
Pro tip: if you want to check if a nuclear reactor design is vaporware or has real legs, you check their application with the NRC (nuclear regulatory commission). It turns out that the NRC does have a page for Kaleidos [1]. You can even go and see what documents Kaleidos submitted this month. They submitted a request to be exempted from some regulation called "10 CFR 55", which they feel is not applicable to them. I have no clue if that is the case or not, but at least they seem to be in fairly frequent contact with the NRC, and that's good news.
[1] https://www.nrc.gov/reactors/new-reactors/advanced/who-were-...
10 CFR 55 covers operator licenses. The regulation does allow exemptions in certain cases where licensing isn’t necessary.
https://www.ecfr.gov/current/title-10/chapter-I/part-55
I'm skeptical, not because it can't be achieved, but because it's not that practical.
Diesel generators are "great" because diesel doesn't evaporate. You can have it there for years, and with good design, it just springs up the next day.
This nuclear reactor has to be connected for fleet monitoring if you want to operate it. Which excludes it from many real life scenarios where diesel generators are used.
Maybe for remote locations where constant power is needed (Antarctica and such), but I see their uses being very limited.
> Diesel generators are "great" because diesel doesn't evaporate.
LOL, no. I see, you have never worked with large diesels meant for backup.
If you just leave diesel fuel alone, then over time (6-9 months) the residual water separates at the bottom of the tank. And then various microbial life springs into action, happily living off all of that free energy. While there's some dissolved oxygen, it will happily use it to oxidize the fuel. But even without oxygen, the bugs will try to live off energy produced by polymerization of unsaturated hydrocarbons.
Polymerization == gunk that clogs up your fuel filters.
So you have to periodically clean up diesel fuel by removing water and filtering the gunk out. It's called "fuel polishing". Large diesels will have fixed systems, for smaller diesels, sometimes mobile systems are used like these: https://fueltecsystems.com/equipment/pneumatic-systems-2/
If I Google "diesel shelf life", the most common answer is 12 months. Do you have a better source? Propane probably makes more sense for fuel that needs to sit around for years.
Do you know the shelf life of TRISO fuel? I imagine it doesn't matter because it would be very expensive to build a reactor and not switch it on.
Diesel will degrade with exposure to oxygen, but a diesel engine can burn pretty much any flammable liquid that you can meter out. It really comes down to the engine itself and if it can handle less-than-perfect fuel.
It can even burn its own lubricant oil and die in a screaming runaway fashion!
I'm sure a nuclear reactor can manage that too if it's a competition :p
Not sure it will sound as nice though. In fact I don't think I have heard the sound of a runaway nuclear reactor. Maybe due to the turbines it can sound exciting?
Maybe the silence of the turbines when the water runs out ...
Anecdotally, I came across a large (for a single user) quantity of diesel 9 years ago. (Nothing exotic - a company went titsup and I was the only one both bidding for and capable of removing the diesel from their premises within an acceptable time frame; I got approx 80% off the pump price at the time.)
I still run my tractor and Land Cruiser off the stuff; the tractor had an outing today. Granted, neither of those engines are very particular about the fuel they are given, but still...
(Water drained off every few months, also a biocide is added to keep the diesel gunk at bay.)
I mean if you trying to run that fuel in a performance application where you are pushing the fuel to its absolute limit, it might be bad, but most diesel engines can be run on nearly any burnable oil, you just get less power out and a bit dirtier burn.
They give similar specs ideals about gasoline fuel going bad in 3-6 months, and yet 95% of gasoline engines will still run 2 year old fuel fine because they aren't pushing compression ratios to the absolute possible limit, and half of the performance engines that do push limits these days have adaptable computer controlled compression and sensors which will figure out how much it can push the fuel.
If I put 5 year old diesel fuel into any regular diesel motor or generator or vehicle and it didn't start up, I would be extremely surprised, and be most worried that the fuel either wasn't diesel fuel to start with or had a wide open hole in the container that a bunch of rain water drained down into.
That said, if I had some kind of tuned up diesel motor that I was trying to push 800+ HP out of, I probably wouldn't use year old diesel fuel just in case. High performance motors like that are already straddling the line between working great and catastrophic failure and using old potentially bad fuel only adds to it.
> This nuclear reactor has to be connected for fleet monitoring if you want to operate it. Which excludes it from many real life scenarios where diesel generators are used.
I don't understand this sentence, why does connection to fleet monitoring preclude using this microreactor as opposed to a diesel generator? Can't you just hook a starlink up to it, and program it to shut down in the event of prolonged comms loss?
Adding an Elon company to the mix might make the reaction unstable.
I don't have any first hand experience with diesel generators, but I saw three cases where power was lost and diesel backup was switched on. In two of these three cases, the generator failed (once didn't start, the other time it ran for 30 mins). In both cases it was in scenarios where I'd imagine reasonable care and maintenance were applied.
Am I right that 1MW of solar generation would only take about a football field worth of panels? Of course that doesn't account for battery or other storage for nighttime, etc. but seems like it would be far cheaper and far less regulatory issues unless you really needed that much power generation in a very small footprint.
"Only"
Looks like a giant part of the value is that it can be shipped in, dropped on the ground on site, turned on overnight, and it only takes up the footprint of a shipping container.
If you have 24 hrs to find an empty football field within a powercable's distance of what you're trying to power, and then fill it with solar panels and batteries, you're gonna have a bad day.
If you ship in a stack of panels, inverters and cables, sure. But maybe you could be a little smarter about it, like a container with all the electronics (inverters, batteries, management) and a bunch of folded, pre-cabled panels that you can pull out across a field. If you bring a couple of those covering a field in a few hours shouldn't be that hard and could be ready for use instantly provided the batteries are charged at delivery.
You also have to make sure there's an empty football field onsite. That's a much harder ask than dropping a shipping container in a couple of parking spots.
That is a solved problem https://en.wikipedia.org/wiki/BLU-82
Not sure if you’re serious. Is this something you’re proposing be used in an urban environment?
Using a bomb to flatten the nearby trees/debris/buildings/people to make way for solar panels strikes me as not preferable to a clean standalone box providing a MW of power for 5 years at a time.
Also the environment would thank you for choosing nuclear over this.
Blowing up the home of birds and countless other species, yeah ok. Blowing up the the home of humans that can be warned and evacuated effectively, you must be kidding right!?!
I get that you don't like the idea in general, no matter who it is dropped on, but take a step back and examine your reaction.
Wait are you seriously equating the home destruction of birds and humans? You’re trying to call me out for seeing those as not morally equal?
Dude, take a step back and examine your entire system of ethics.
Yes, I'm calling you a human supremacist [1].
There are plenty of examples of things that are not equal like skin color or gender and yet we - I assume you are not racist or sexist - try to treat equal. Drawing a hard line in the sand at human and everything else seems well ... really an Orangutan and a Human are so different that they deserve completely different rights, what about whales that have languages likely as complex or more complex than humans? Don't get me wrong I don't believe a cricket has the same emotional reasoning capabilities as a human. But it strikes me as very human to define in-groups people like you and people or beings other than you and using that as justification to do horrible things to them.
[1] https://dothemath.ucsd.edu/2024/08/mm-12-human-supremacy/
First of all, you've created a strawman out of what you assume I believe.
> But it strikes me as very human to define in-groups people like you and people or beings other than you and using that as justification to do horrible things to them.
This is a behavior nonspecific to humans...not sure if you've heard of it, but there's this fascinating emergent behavior among wild animals that naturalists have occasionally observed - in colloquial terms, they've labeled it "predator and prey".
Comparing the industrialized usage of animals like pigs and cows to "predator and prey" is not a good comparison in my opinion. For the record I'm totally fine with indigenous humans hunting and killing animals. The scale and industrialized nature is what makes a big difference I find, the same way killing someone in self defense and genocide both involve the murder of humans, yet there is a qualitative difference I wouldn't ignore.
Many predatory species engage in behavior that limits their hunting to avoid making their prey extinct. Right now extinction rates are >1000x above the baseline a couple hundred years ago. What we are doing to the biosphere we are currently part of is short sighted self sabotage - which is in large parts fueled by a wide spread human supremacist mindset.
I'm pretty sure GP is joking ...
TBH the line between extremism & satire can be very, very thin.
What urban environment? Isn't this about to be able being deployed somewhere way out there? Where diesel is impractical because of logistics? In which urban environment that would be the case? And wouldn't that environment have to be flattened, torn down, and rebuilt to be economically viable again, anyway?
Are you're seriously comparing a few containers of fold-out solar panels and batteries to a portable nuclear reactor?
Let's do the math: To match even a 1MW reactor, you'd need 2,000+ panels, inverters, batteries, mounting, and approx. 120-150 man-days of labor...and that's with pre-cabled gear. You're still looking at 8+ containers, a full crew, and a full 10-14 days to deploy, not "a few hours."
A nuclear microreactor doesn't need 54,000sqft of land or weather-dependent storage. Nice idea for a solar camp but not a replacement for a compact nuclear source.
Let’s not pretend to be offended that someone else is making up an unfair scenario, as if you guys didn’t already make one up.
Nobody’s dropping off a nuclear fucking reactor in the middle of a disaster area on six hours’ notice in any universe other than the bizarro one invented by their PR firm.
You’re maybe running water desalination for an island that has known for years they want an alternative to shipping in diesel, or you’re shipping diesel generators to a disaster area because the Red Cross has a stack of them in a warehouse ready to go.
Or you’re some hyperscaler data center hoping to not have to maintain fifteen generators onsite for you eight server rooms (8 + 4 + 2 + 1 = 15), and those could potentially be replaced with battery systems or gas turbines. And again, on six months or more of notice.
If someone had an easy non-snake-oil nuclear solution we would be using it already. A realistic person would assume incremental improvements in portable nuclear over the next twenty years, not an overnight success.
> If someone had an easy non-snake-oil nuclear solution we would be using it already.
Nuclear has been pretty much regulated to death. This is definitely not true.
> Nobody’s dropping off a nuclear fucking reactor in the middle of a disaster area on six hours’ notice in any universe other than the bizarro one invented by their PR firm.
Why not? It absolutely has the potential to be cheap, reliable and safe. That sounds like a fantastic use case. The biggest reason we don't do that is environmental lobbying regulating the technology into oblivion.
I grew up an hour from a lake you couldn’t swim in because the cooling equipment for the plant caused microbes to grow that cause encephalitis. Those regulations are written in blood and you’re fantasizing about an unattended reactor as the next generation? No. Dream on.
I’m not saying it’ll never happen. I’m saying the work hasn’t been done and this is more snake oil.
And then there’s the physics and logistics the other responder mentioned. For conventional reactors, that much concrete of a very specific and difficult quality to achieve in that many layers is expensive. The last one I heard about being built they had to jackhammer off many feet of the base because they missed spec, and lay it all over again. And the carbon footprint of that much concrete is not tiny. The embodied cost of a built plant is huge, and repairs are constant. They aren’t free, even if you ignore heat pollution, and we are running out of runway for that conceit.
FAA regulations are written in blood, too - and yet our private aircraft technology is ancient (and likely less safe than modern tech could facilitate) because those same regulations make the cost to innovate astronomical. I would not make the mistake of believing that regulations do more than freeze our tech in a relatively safe local minima.
You're describing the engineering problems of rarely-produced machinery, and seem to imagine that we can't figure out how to do that better, and cheaply, at scale? The potential market for a shipping-container-sized MW-scale power supply is likely huge.
Nuclear power was dying due to cost overruns already before TMI.
The blaming everything on regulations is a nice scapegoat when the technology doesn’t deliver.
We left the piston steam engine to the past, now it’s nuclear powers time to fade into museum pieces.
What if robots/drones/automation was doing the deployment?
You’ll need some peacekeeper drones, too - gotta keep the people from coming back after you evict them to make space for the solar panel fields!
I'm not comparing anything, I'm just saying a solar solution doesn't have to be discounted because of my OP's incredulity about deployment characteristics. No need for hostility.
the sun doesn't shine at the poles 6 months of the year. it usually doesn't shine underground or deep underwater. etc.
In places solar panels make sense they would certainly be used, but that's not everywhere.
In Svalbard they have trouble retaining the skills to even run a large scale diesel.
Now try foisting a nuclear reactor on them.
https://www.spitsbergen-svalbard.com/2024/04/09/longyearbyen...
I can imagine a Falcon 9 dropping off an automated package that unrolls/inflates the solar panels. Security would be provided by even more drones.
Still need a place to unroll them. Unless you have a football field of empty space in that falcon 9, too.
The falcon can level the field with its landing blast.
Touché
You're not accounting for location at all.
Nor is that generating electricity at night.
Plus battery storage.
And it's closer to 4-6x football fields if you did it in say, San Francisco. 4-5x football fields in Kansas City. 6-8x football fields in Chicago. Again, plus battery storage.
How many power problems would be covered by making a battery the size of this device
Depends entirely on how you charge the battery.
Not many, it’d be roughly 1MWH of storage, based on looking at battery storage in half size conexes that are currently available for sale. A 1MW reactor or diesel genset can put out 1MWH every single hour for as long as they have fuel.
I was able to find some that were a bit over 3.1 MWH.
It is unlikely that those 1) cost as much as a nuclear reactor or 2) are exactly the amount of available space you have. So 2 or 3 aren’t going to solve your water desalination problems but might solve your intermittent power ones.
It depends on the size of the load.
Just FYI, every building that is required by law to have emergency backup power has an engine-generator set. There are zero exceptions to this rule. If batteries were able to serve critical loads like hospitals and emergency dispatch centers, they would be allowed to be installed for that purpose, but they aren’t. This should end the argument about battery backup, at least until battery storage density reaches a point where it can serve those loads.
FWIW I sell and run electrical work
To add, grid-scale batteries do make sense if you have a ton of cheap land. Most facilities that need backup power aren’t in areas with lots of cheap available land for battery installations.
The kind of backup power needs that hospitals, data centers, and other critical facilities have (multiple MWH per hour at minimum for large facilities) and the durations they need to operate for, combined with the land prices in the areas where they are situated, make battery backup for critical power needs uneconomical due to the space needed with current battery energy density.
zero
That’s the sort of bullshit answer you take to Reddit, not HN.
Name the problems a battery half the size of a flatbed trailer "solves"?
That’s not half the size of a flatbed trailer and nobody with space for one trailer has real problems to solve that can be solved with a single delivery.
It’s cargo container size and that’s apparently a few MWH of battery these days.
I don't really understand this line of thought and where you're going with this or the point you're trying to make.
It depends on where you're at, but for a sunny place yes; somewhere like London a panel can harvest ~100 W/m^2 (0.5 MW for a football field with 100% panel coverage) averaged over the whole year, while in Arizona it's more like 230 W/m^2 (1.2 MW for a football field). NREL has some great insolation maps here: https://www.nrel.gov/gis/solar-resource-maps
For a permanent installation I would agree that solar would usually make more sense, but the mini reactor might be better in scenarios where it's replacing a diesel generator - emergencies, temporary events, confined spaces, etc.
It requires space, setup time, and then there's the intermittency issues. You'd need enough batteries to store, what, 12 MWh? 20? More if you're accounting for cloudy days?
People just want a compact solution to generate power, not a whole separate project.
Wouldn’t the point be that it works at night too?
“Only” a football field is a lot of space. A 1MW diesel genset on a trailer is about 30’ long by 8’ wide by 10’ tall, which is 0.4% of a football field.
At this point, I'll assume that the relevant US regulatory agencies are competent, and skip the safety issues, etc.
That used to be true, not so sure my trust in our institutions is high these days. Seems a few million $ donation to the right people can make all regulations just vanish.
Yeah there's currently a large push to dismantle the Nuclear Regulatory Commission and give reactor regulation authorities to the states.
For all the faults of the NRC (real or imaginary), this still strikes me as an extremely bad idea.
That's pretty much always been the case. It's just much more flagrant and in the open now.
> That used to be true
No, that used to be believed to be true. We're just seeing the curtain come down.
The food pyramid, the CIA's "war on drugs" in South America, the wars with Iraq, Libya.. Just to name a few. Why do we pretend like bribery and corruption is this new thing?
That sounds like an excuse to abide the open corruption that's occurring under the right-wing regime in the US today.
No it's not. I'm replying to the guy that said "That used to be true", because it's obviously not true.
And that comment is overly-fastidious.
Here's a related company, Ultra Safe Nuclear, making TRISO fuel units.[1] They went bankrupt in April 2025.[2] They at least got as far as making fuel units, although I suspect the video shows dummies being made, because they are not taking enough precautions for handling enriched uranium.
[1] https://www.youtube.com/watch?v=uR7VDqUbaCg
[2] https://nuclear-news.net/2025/04/04/update-on-the-bankruptcy...
I'm not filled with optimism about this concept. Let's work backwards from crash safety (say a reactor on a truck getting t-boned by a freight train). The radioactive material needs to be held in an armored containment to avoid release. That would have to be roughly comparable to CASTOR containers in terms of its resilience. But these containers have limited capability of passive thermal energy dissipation (Google finds models that handle 10kW to 45kW thermal power generated in the interior). This would be approximately the ceiling for the direct thermal power output that is still reduced by limited efficiency of heat-to-power conversion.
This is admittedly napkin math, but it should be good enough to set expectations.
You are thinking accidents. I think we need to be thinking deliberate attempts to compromise these things and all the security measures needed to mitigate against that. And most importantly, the cost associated with that. Which comes on top of already significant cost.
The naive notion of we'll just ship these all over the place by the thousands and it's going to be fine is not going to withstand a lot of critical thinking very long.
I was indeed not thinking about deliberate attacks. But that doesn't change the result much as I assume that the CASTOR containers that I used as reference are designed to withstand all of these worst case scenarios.
Unfortunately, this chain of messages underscores the importance of keeping humans in check with eachother, and the machine.
Hundreds of thousands if we're talking about meeting growing demand. Which doesn't give me a lot of hope for solar either though.
Solar already runs circles around nuclear when it comes to cost. Typically combined with batteries. The combination is popular and cost effective.
With nuclear it's all rosy and optimistic. But also almost 100% hypothetical. And the industry has a piss poor record delivering on its promises. 200-300% cost overruns are routine.
We won't see more than a handful small small nuclear reactors for years to come. We might get to hundreds by the 2040s or so. Maybe growing to thousands or even tens of thousands by the 2050s under the optimistic scenario.
Most of these things have the power output of a handful of wind turbines, of which we have close to half a million right now around the world with more coming online all the time. The challenge here is that wind turbines are just stupidly cheap and scalable at this point and still getting better.
SMRs will remain very niche for a long time even if they do get their cost levels under control. Which is a big if. Thousands of these things would barely move the needle in terms of power output. Essentially all of the expected growth in electricity demand for the next few decades is going to be met by wind and solar supported by batteries.
From the FAQ:
> The plan is for the small amount of spent fuel [..] that comes out of our reactors at the end of their duty cycle to only be temporarily stored on-site until a federal repository or interim storage solution becomes available.
>The NRC is legally required to ensure that, in the event of bankruptcy that the site is secure and the spent fuel remains safely managed before ultimately transferring over to the U.S. Department of Energy's (DOE) possession
So basically like with all other nuclear, the tricky parts with unknown costs are handed over to future taxpayers. These costs are thereby removed from the estimates in Kaleidos business plan making it seem like it's a viable business, which is isn't otherwise.
Meanwhile the founders get rich today, since immense amounts of money has to be presented upfront, before any energy is produced at all.
The obvious replacement for diesel generators today is solar+batteries, which is evident in many countries that used to rely on small scale diesel generators already.
If they go bankrupt who is responsible for the waste?
you are :D
yikes from their FAQ:
"The plan is for the small amount of spent fuel (the volume of the spent fuel in one reactor is equivalent in size to just two Walmart gas grill propane tanks) that comes out of our reactors at the end of their duty cycle to only be temporarily stored on-site until a federal repository or interim storage solution becomes available. "
They don't even have plan while the exist now.
Well no one does. The feds cancelled Yucca mountain and so there's nowhere for anyone to put nuclear waste. By law it belongs to the feds.
So everyone just leaves it in the reactor's parking lot for now, in big concrete and steel dry casks.
> equivalent in size to just two Walmart gas grill propane tanks
Is this a real measurement in tank sizes? Why not just say two 20lb tanks? What if I bought my tank from Home Depot? Are they a different size? Do they think using Walmart makes it more relatable?
>Is this a real measurement in tank sizes?
That's only 0.393% the size of a football field!
Seriously though, isn't a lump of radioactive material that size actually huge?
I mean that is exactly what we do right now with all nuclear waste. Without a nuclear material repository there is only so much you can do. You don't want to just dig a simple hole somewhere and start tossing everyone's high level waste into it, that would just be asking for a massive disaster.
That's the right question to raise up.
Could this be associated to a supposed recent State Department approval?
“I just approved a program to deploy small modular nuclear reactors built in the United States to an allied country to help with their sort of energy infrastructure.”
“Which allied country would that be?”
“I can't tell you. It's not public yet.”
From Interesting Times with Ross Douthat: The DOGE Alum Asking if Foreign Aid Is America’s Problem, Jul 31, 2025
How much does it cost? Would love to buy one with the HOA and run our own micro-grid while exporting electricity to the local utility.
When HOA gets too powerful.
This is bringing “My HOA went nuclear on me!” to a whole nother level.
When the DOE comes after your HOA.
meh, most HOAs can take on the DOD
Not in my back yard!!
From the headline I was assuming it was a tiny 20kw job.
But it being a 1.9mw(thermal) makes sense.
I wonder what the support requirements are, like how do you yeet the heat to make it efficient?
Also containing super heated helium seems hard for any length of time. I wonder what the operating lifespan is.
Meet EMD DDA40X [1], the most powerful diesel–electric locomotive model ever built on a single frame incorporating two diesel engines with an effective power output of 4920 kW. Given the expected losses in the diesel engines (~40-45% effective, 60-55% waste mostly in the form of heat) and diesel-electric traction system (power generation, traction motors, gearing etc, around 80% effective) which gives a total system efficiency of around 35%. Assuming most of the waste energy ends up as waste heat this ~30m long locomotive (a bit more than two 40ft containers) needs to shed around 9 MW of waste heat or about 4 MW per 40ft standard container length.
[1] https://en.wikipedia.org/wiki/EMD_DDA40X
They say it needs to be refueled after 5 years and that it can be done 4 times for a total lifespan of 20 years.
1.9 MWt still seems like a huge amount of energy/heat for something that fits on a truck and is supposedly air-cooled (they claim no water is required).
Where does all that heat go?! They must have some very impressive fans.
Heat transfer has the lovely property of scaling nonlinearly by temperature difference. You need a lot of big fans to cool your CPU from 75C on the die to a 25C room, instead of a 50C difference these reactors will dump heat at hundreds of degrees C warmer than the local environment.
Yes, that's crazy. They say up to 1 MW electric which would mean (33% efficiency) 2 MW of heat to get rid of with air cooling. Later they mention facility heating which sounds more realistic, I guess?
I mean its not that much different from a diesel generator, they are around 30% efficient, so they'd also be kicking out the same amount of heat?
https://www.generatorsindustrial.com/products/1mw-diesel-gen... has a simple radiator.
but then the heat profile is different I suppose, and the efficiency doesn't depend on being able to shed heat.
[dead]
A startup where most of the money were spent on that animation on the website.
You'd be surprised at what the CAD software can do now in 3D renders. You have to design the thing in CAD anyways, so it's not like the 3D team had to model it from scratch. You could probably just do this with a request on Fivr. These aren't your parents 3D prices any more
Everything I've heard is that micro-reactors produce far worse waste situations than larger scale options.
I think there's a huge opportunity for nuclear power in the world today.
But: all these micro-reactor strike me as disastrously bad idea, that's all too likely to offload incredibly complex nasty gross problem to the future. Costs that alas will likely be handled as network externalities, as drains and damage against humanity and people and government, that the creators and purchasers of these device will skate through with comparatively little injury.
Considering that fossil fuels "solve" the problem by literally dumping its waste onto the atmosphere, endangering the global ecosystem, and we're still merrily using them...
I think it's a bit melodramatic to say microreactors offload nasty environmental problem to the future. Also, their environmental problem is literally at the scale of "Drop them in an abandoned mine somewhere, where they cause zero harm to the world, and we will have a few centuries to figure it out."
Recapturing the CO2 from the environment of fossil fuels is almost impossible is almost impossible. Recapturing radionuclides is much much more difficult. Also the duration in which radionuclides are a problem has to be taken into consideration, making even babysitting nuclear waste extremely expensive.
Counterpoint: we've been powering ships with microreactors for decades.
And we're starting to have to decomission them! At absurd costs!
We just awarded $0.5B to decommission the USS Enterprise (CVN 65), the first nuclear aircraft carrier. More will follow! https://theaviationist.com/2025/06/03/uss-enterprise-dismant...
The DoE has been helping to decomission Los Angeles class attack subs for a while now. Here's a piece on that: https://www.defense.gov/News/Feature-Stories/Story/Article/4...
It require enormous care & effort. It's fantastically costly. Do I think it was worth it? For a mission like this: I think yes. For the good of a nation. And a Nation that hopes to still be around to take care of the problem, the complex decomissioning decades latter. But I have so little faith that private interests will endure and bear their own responsibility for this awesome but deeply corrupting irradiating force.
That CVN also happens to have 8 reactors in it
Most nuclear-powered ships have reactor powers in the 40-300 MWt range, a bit beyond the typical 10 MW limit for 'microreactors'
This was new to me so I looked it up- "MWt" means Megawatts Thermal - e.g. the heat output of a reactor, which would be turned into a smaller value of MWe- Megawatts Electric
We sure have.
And it is a money pit.
And then you have things like this: https://www.navytimes.com/news/your-navy/2019/01/10/two-sail...
It's proof that you can build a robust and safe reactor, but like all things under triple constraints it will not be cheap.
Yep. And the Russians have had pluggable nuclear power for years now.. on barges: wikipedia.org/wiki/Akademik_Lomonosov Decommissioning no doubt will consist of scuttling them over a trench. Definitely going to wake the Kraken.
Hopefully this needs a smaller crew to operate than a Nimitz-class aircraft carrier.
The nukes on a carrier are a much smaller team within the carrier's full crew though. So if you extracted the guys that glow in the dark, it might be more inline
Meh it's a little bit worse, because smaller reactors burn a smaller fraction of their fuel and therefore make more volume of high level waste per kWh generated.
But it's not THAT much worse. Nuclear waste is already ridiculously small in volume per kWh vs. any other fuel-burning energy technology. Right now all of the waste we've accumulated from making 20% of the country's electricity for decades fits on a football field 3 meters high (that's pellets only, if you include individual dry casks it's 135 meters). So if we make lots of small reactors that are a bit less fuel efficient we might need 2 big football fields deep underground rather than 1. Compared to all the particulate and CO₂ emissions other sources make I'm just not that worried about it. Recall that fossil kills ~6 million per year from particulate emissions alone. Commercial nuclear waste has never hurt anyone, and is unlikely to do so in the future.
Not to mention if we really wanted to and/or had enough of a supply of it, that higher grade waste can in large part be recycled and used again.
From a humanistic species survival perspective, we should conserve nuclear energy for interstellar travel.
If interstellar travel ever becomes possible you'd already have access to all the resources of the solar system as well as the output of the entire sun.
The scale of the problem l, technologically simply renders earthbound resource constraints irrelevant.
Like you're into "synthesize antimatter with solar power" at that point.
> If interstellar travel ever becomes possible you'd already have access to all the resources of the solar system as well as the output of the entire sun.
I'm not going to argue circular conditions, this is precisely why we should preserve dense energy sources, first an alternative abundant energy source must be demonstrated, before squandering it locally.
> The scale of the problem l, technologically simply renders earthbound resource constraints irrelevant.
Hidden in such statements is the implicit assumption that mining the solar system for fissile materials is less energy intensive than mining them locally.
We should make sure interstellar travel remains affordable by the time we decide to afford seeding other star systems.
Nothing prevents interstellar travel with current technology, it would just take a long time. We should keep this mode of travel, where survival on the ship is powered with known feasible technology (nuclear fission) on the table and conserve fissile materials until we succeed in compact fusion plants, in that case this constraint no longer is an argument to preserve fissile materials.
Speculating other energy storage technology like "antimatter storage as a battery to store solar power" before launching to another star is just that: speculation. We shouldn't squander fissile materials on the basis of feel-good speculation.
No the assumption is that the magnitude of energy involved in interstellar travel is so large that it dwarfs all other considerations. If you can't afford to expend the energy to travel around the solar system to acquire resources, you definitely can't afford to engage in interstellar travel.
And then of course, if you can't afford the energy to sustain a human population on Earth in decent conditions, you also definitely can't afford interstellar travel. Because implicit in your assumption is that somehow the extremely limited number of people who could be put on a slow ship (and by slow we're talking thousands of actual years minimum at "current technology" levels) will somehow be able to command and control all of Earth's fissile resources.
Interstellar travel to… where? It’s like saving your money for an immortality treatment that’ll eventually hit the market. Well yes it might, someday in the far far future. Practically speaking, this money should better be invested in your health now instead, aka. preservation of the only spaceship we have right now—Earth.
To different star systems obviously.
Short of discovering portals or wormholes (natural or artificial), we should only assume demonstrated space propulsion technology to make the trip. With current technology its a long trip, and its cold and dark inbetween 2 stars. We should definitely conserve fissile materials until we demonstrate fusible materials for reliable power generation.
The USSR did it first! No, really. There was a mobile power plant: Pamir-630D ( https://imgur.com/a/rCexHAA ).
It was even deployed to provide power to a remote Arctic outpost. It had to use an exotic coolant (basically, a rocket oxidizer) to make it work, and it had to be placed far away from anything else. The shielding was not enough to bring down the gamma radiation to a safe level when the reactor was active.
Not sure about who was first but McMurdo station in Antarctica was for a time powered by a nuclear reactor almost identical in power to the one being discussed here: http://large.stanford.edu/courses/2014/ph241/reid2/
D'oh. Thanks!
I forgot about it, because it was delivered by a plane, not a truck.
Neat, I never heard of that! Im surprised there isn't even an english wiki page for it, I had to translate russian wikipedia and even that was a bit limited in information to satisfy my curiosity so ill have to look at other sources.
I actually was mistaken. The photo is from an earlier project: TES-3, from 1960. It was a system with 4 mobile units and a reactor that needed to be buried for shielding.
https://www.ixbt.com/live/offtopic/pervaya-v-mire-peredvizhn... (German Wiki also has an article with an image: https://de.wikipedia.org/wiki/TES-3 ).
I remember reading about it in an encyclopedia as a child.
Lookslike more vapourware:
* no prices
* no dates, just "2026" (elsewhere 2028).
* no pictures even of prototypes just computer graphics.
* helium is notoriously hard to keep from leaking
* it's all just way too promising and convenient and appealing. Who doesn't want a reactor that fits in a shipping container? Who doesn't want reliable, clean energy? Who doesn't like hospitals and the military? Does it also release puppies and cure cancer?
Looks aspirational to me. 1Mw electricity at 30-100% efficiency (100??) and 1.9 Mw heat via air in the volume of a shipping container? That's moving a lot of air. And I'd want fail safe, passive control "rods" (what happens if the helium leaks out and the heat isn't being removed) before I'd sleep easy with one in my back yard.
This type of fuel basically cant melt so with no helium it would just heat up and natural convection would cool it.
>We have fully modeled worst-case - as well as lesser-case - scenarios for an accident or leak. The analysis has shown zero impact experienced by the public.
Well that's a relief.
So if the truck were electric, it could run for >5 years straight, even uphill?
Jokes aside, very cool tech.
I have oil clients who would love this. they have to run expensive engines left and run on site
The poetic irony!
A flame chart of energy consumption to customer from well-head typically shows an astronomical amount consumed at head in the gas train. It can be a significant sub of the total available energy consumed at the head and in pipeline and shipping, to produce the output which can be sold.
Unfortunately much of it can't be sold or shipped off site and if it isn't used, will be fugitive gas emissions or flared.
Replacing the diesel and other fuels used on-site is good. But it's only part of the story. Running the train would certainly burn a lot of gas, so replacing that would be good.
(-not a fan of SMR for a variety of reasons, mostly political)
Thoughts on using stranded gas as bitcoin miners?
Inventing reasons to perpetuate fossil fuel extraction is counter productive.
It's already being done.
Sounds too good to be true.
Hope it is true though.
I have no idea if the testing will go well, if the regulatory/political environment will accept it, but as far as the company, the tech and the promise of testing?
That is real.
https://www.energy.gov/ne/articles/radiant-completes-study-f...
1. Can I have one in my driveway?
2. Why only refuelable 4 times?
3. Is it really safe to fly around with in an airplane? Can major airlines help distribute these via standard flight routes to reduce cost?
4. What happens when home base monitoring detects a problem with the reactor? (And why isn't this covered in the slides to put the audience at ease?)
I would imagine refuelings are limited because at some point you are going to need to inspect and potentially replace some of the critical components that have been exposed to hard radiation. Materials that we would think of as stable can degrade in such high radiation environments. Like a large chunk of steel can have its crystal structure disrupted as atoms get displaced by high energy neutron strikes or other fission fragments, changing its material properties and making it weaker or in most cases more brittle. Localized impurities can also be formed by either alloying elements in the metal being displaced the same way, or from transmutation of atoms into other elements from the strong radiation. And along with disrupting the material strength those impurities can cause hot spots in the metal causing more stresses and fatigue and further reducing it's lifespan.
We are actually pretty good at making alloys and materials today that can resist radiation problems better and more predictably these days, but there is still a bit of randomness from manufacturing variables that means you need a pretty large safety margin to prevent problems. They probably would work for a dozen refuelings, but the consequences of a reactor breech are too high to not have a massive safety margin. And maybe after they ran these for a few refuelings and inspected enough of them they could bump up the refueling limit before inspection or replacement a little.
> 3. Is it really safe to fly around with in an airplane? Can major airlines help distribute these via standard flight routes to reduce cost?
These are too big for your standard air freight network or aircraft (that is, it's significantly larger then any typical ULD [Unit Load Device, shipping containers for airplanes]).
So it'll definitely be a charter to get one delivered. Weights going to be the big determinant in cost, dimensionally it looks like you could get it into anything bigger then a C-130. I doubt you'll be within the C-130s weight limits though.
Not a bad idea. But what if we scaled it up, say to 1.0GW. It wouldn't be portable, but it would sure be useful. So of course we instead take the fuel to the reactor. We could even call it a nuclear plant, because it doesn't move. Can we do that instead?
Looks basically like the TRIGA reactor design (without the water shielding). Seems to have similar challenges with rapid load changes. At one time I thought NASA was looking at something like this tied together with a battery pack that would allow for rapid changes in dynamic load without a lot of stress on powering up/down the reactor. And now I can't find it. Sigh.
If you're a billionaire building your bunker this would be the ultimate off-grid power source :-).
It's a lot different from a TRIGA. It doesn't have hydrogen in the fuel and it uses high temperature/high pressure helium gas as the coolant (vs. water in a TRIGA).
We did run a nuclear reactor in space once that did use TRIGA fuel. It was called SNAP-10A. More recently, the Kilopower test ran a reactor on land but intended for space with a U-Mo metallic fuel.
Fantastic if true.
I'm sure there's a few catches or weed already have them back ordered globally but frankly anything that normalises using these self heating rocks to boil water gets my vote :)
When can I get a smaller one to power my AirTag?
I know that this is a joke, but reactors cannot scale down that far. Unlike an electrical source powered by radioactive decay (like certain pacemakers [1]), the minimum mass for a nuclear reactor includes several kilograms of material. It's possible to shed neutron moderator mass by using high-purity fuel operating on fast fission, but these require more fuel to go critical so they still have multi-kilogram masses.
[1] "Plutonium powered pacemakers (1974) https://www.orau.org/health-physics-museum/collection/miscel...
That may actually be not that far away:
>first nuclear battery can deliver 100 microwatts of power and a voltage of 3V
>plans to produce a battery with 1 watt of power by 2025
https://www.independent.co.uk/tech/nuclear-battery-betavolt-...
I want one to take camping
Bottom line: nuclear waste is forever while their promises are a fart in the wind. If they find any rules or regulations or judgements from any courts to be inconvenient they need only shove some cash up Trump's ass and then, POOF! all their problems are solved... except that, yeah, the waste will still be there. Oh, well - somebody else's problem. MAGA!
Is it real?
From their job listings:
> Additional Requirements
> Must be willing to work extended hours and weekends as necessary to accomplish our mission.
So... not yet.
It will be tested next year so it's not real yet. https://radiantnuclear.com/blog/dome-selection/
Yes it's real. There are a lot of good people who I know personally and a lot of funding going into this. They have a plan to get fuel and will try to turn the first one on in Idaho soonish (like next year)
I was hoping the FAQ would answer that but, as I expected, I was disappointed.