Forgot your password?
Close
typodupeerror
Power

Small Modular Nuclear Reactor Reaches Criticality In First Test (arstechnica.com) 107

Posted by BeauHD from the latest-developments dept.
An anonymous reader quotes a report from Ars Technica: Just over a year ago, the Trump Administration issued an executive order meant to accelerate the development of nuclear power in the US. While an entire startup ecosystem has developed around the use of different -- and typically smaller -- reactor designs, only one of them has been fully licensed so far, and there are no plans to actually build any instances of that design.

The executive order directed the Department of Energy to have three different reactor designs reach criticality in a bit over a year. On Thursday, a startup called Antares announced that a test reactor it had placed at the Idaho National Laboratory had reached criticality, making it the first new design to cross this threshold. Criticality means that the nuclear reactions inside the hardware had become self sustaining; it does not mean the reactor had started to generate power. [...]

At the moment, Antares is just testing what it calls a Mark 0 reactor, which is not connected to the power-generation portion. Instead, it's being used to validate the company's modeling of the physical conditions in its reactors and generate safety data that can be used during licensing applications. Attempts to run the entire system, including electrical generation, are expected to happen next year. While the work was done at a Department of Energy Lab, the company is working with the Department of Defense's Project Pele program for developing a mobile nuclear reactor. The company has also received support from NASA.
This discussion has been archived. No new comments can be posted.

Small Modular Nuclear Reactor Reaches Criticality In First Test More

Small Modular Nuclear Reactor Reaches Criticality In First Test

Comments Filter:

  • Out of control demand for power (Score:3, Interesting)

    by rsilvergun ( 571051 ) on Friday June 05, 2026 @11:32PM (#66177648)
    A lax regulatory environment and a technology that is outclassed by wind and solar in virtually every single metric except space usage in a country with nothing but space?

    Hey what could possibly go wrong?

    Really looking forward to having nuclear powered data centers dropped in the middle of my community by finance Bros pretending to be tech Bros...

    • Re: (Score:3, Interesting)

      by CaptQuark ( 2706165 )

      A lax regulatory environment and a technology that is outclassed by wind and solar in virtually every single metric except space usage in a country with nothing but space?

      The output of a SMR is heat. That heat can be used to power a steam turbine or it could be used to generate heat directly where heat is needed like industrial or chemical plants. Imagine a SMR that could produce electricity, heat, and desalination in high latitude locations like Alaska. Or a small version could be used at McMurdo Stati

      • No one is doubting that electricity is useful. The intended output of nuclear power plants is great: power.

        The worrying, doubting, lingering is, "Will they explode?" The pollution from nuclear power plants potentially outweighs the benefits.

        How much pollution will the intentionally/unintentionally have?

        • Explosions aside, the ratio between surface and capacity is not exactly optimal with mini reactors. They'll definitely emit more radiation than conventional plants and the risk of leakage also multipilies.

          • But what is important, at least in America, is answering the question: will this make important people even richer?

          • Depends on what you classify as traditional plants. Solar and wind, you'd have a point. However, coal and natural gas plants emit orders of magnitude more radioactivity directly into the environment in the form of naturally occurring radioactive materials (uranium, thorium, radon, traces of other elements) as a consequence of their normal operations. Fission plants basically only do that during catastrophic failure modes.

        • Modern reactors are meltdown-proof. They will not explode, period.
          • Modern reactors don't explode [youtube.com], but how do we prove it? [youtube.com]. It's disgraceful, really, that reality doesn't always match our plan.

            • Re: (Score:2)

              by jsonn ( 792303 )
              A reactor doesn't have to explode to become a major public safety issue.

          • Great. On the other hand we had two major chemical accidents. Ruptures, leaks, implosion, and more are risks in industrial processes. Solving the turning into an atom bomb problem does not elimate all other localized risk.

        • Re: (Score:3, Interesting)

          by Ol Olsoc ( 1175323 )

          No one is doubting that electricity is useful. The intended output of nuclear power plants is great: power.

          The worrying, doubting, lingering is, "Will they explode?" The pollution from nuclear power plants potentially outweighs the benefits.

          How much pollution will the intentionally/unintentionally have?

          I'll weigh in with my standard "Fission power plants can be very safe. But not when built by humans, with managers, bean counters and others overruling the engineers." Recent examples . Fukushima should be happily providing power today, had it not been built in a place 100 percent certain to suffer Tsunami, 100 percent certain that Tsunami could occur that would overtop the Seawalls - although they probably saved a lot of money by not making them a meter or two higher. Then an emergency power system for

        • It's worth noting that nuclear reactors don't really explode in the way people think of. What they can do is turn into radioactive lava, melt through the floor, and release the highly carcinogenic dust from their system into the environment. They're generally big water heaters without pressure release valves (because the water has the carcinogenic dust in it), so they can burst like any water heater, and they contain zirconium, which reacts with steam at high temperatures to release hydrogen gas, which can

      • The output of a SMR is heat.

        That's yaddieyaddering away a very important metric of just how much it costs to make heat.

      • An attempt was actually made to power McMurdo with an atomic reactor in the late 60s I think. It was the size of a shipping container roughly, and ran on HEU (or HEPu, don't know, don't matter). I say "attempt" because it proved unreliable, and was so temperamental it required a whole team of physicists to keep it going.

        Oh, and because it was small, it leaked neutron radiation that turned the entire container and everything around it radioactive.

        • And of course that was over half a century ago. There have in fact been considerable advancements in many areas of science and engineering in the meantime.

          The first (human initiated) self sustaining fission reaction was in 1942. The McMurdo plant went into operation in 1962. There has been over 4x more time between the start of that plant's operation and today than there was between the beginning of human nuclear power and the inauguration of that plant.

          And, yes, any "shipping container" style reactor i

          • Thank you. I was considering posting to make that point, but you beat me to it. I would like to point out, while I'm here, that the OP's argument boils down to, "We tried it about fifty years ago and it didn't work, therefor it will never work."

            • And my 4x point understates things, because I counted "human nuclear power" from 1942 when it should really be counted from, to be generous, 1951.

      • The output of a SMR is heat. That heat can be used to power a steam turbine or it could be used to generate heat directly where heat is needed like industrial or chemical plants.

        Industrial heat costs pennies per kWh of electric equivalent. There is absolutely no way nuclear can compete for process heat. None. Zero.

        Nuclear can *barely* compete on the electricity front as it is, and that's *dramatically* more profitable than process heat.

        That's why there is a single example of utility-scale nuclear heat in all of history and that was purely a "first!" on the part of the then-soviets.

        Stop reading the nuk-boi propaganda. There is precisely zero market for this.

        ten of these could be prepositioned around the country to generate power after natural disasters

        The Antares design is aro

        • Re:Out of control demand for power (Score:4, Insightful)

          by rickb928 ( 945187 ) on Saturday June 06, 2026 @11:44AM (#66178104) Homepage Journal

          If it were just about the money, then nuclear would not be very attractive.

          But it's the environment, stupid. Compared to fossil fuels, nuclear is an attractive option, cost be damned. Hydro is not without detriment. Solar uses space. Wind is going to be seen as a loser in so many ways, but it is a stepping stone.

          Nuclear is the best option, and SMR among other technologies will improve the option.

          ps - Previous comment about desalination in higher latitudes might, I think, miss the basic equation. Fresh water is more readily available at higher latitudes than lower, until you get into the ice. Nuclear powering desalination in Southern California, yes. Alaska? Dude?

          • Solar uses space

            There's a lot of space available because it doesn't need it all to itself. There's a lot of desert nobody is using, a lot of canals and reservoirs we could cover, a lot of nice safe flat commercial roofs, a lot of commercial glass, a lot of car parks. So since that's not a real problem, can we just legislate it and move on?

            Wind is going to be seen as a loser in so many ways

            Because so many lies are being told about it, yes.

          • Solar uses space.
            Rooftops and parking lots you mean?
            Or what space are you talking about?

            • The serious projects like covering the desert, or canals, which seem really, really clever. It all depends on what they're covering. I guess sometimes not very nice to what they're covering. But it's really about choices. Responsible choices are going to be okay. I'm reminded though that there is no criticism of any power generation method that won't burn you, the scorn and ridicule and dismissal and rejection somehow. Doesn't mean anybody's right or wrong. Oh wait it does.

              • The same people can be right and wrong, because there's a lot of different aspects to most situations.

          • The real problem with solar and wind is that they scale down to the individual level. No government can afford to have its citizens needs be independent of the government. How else will the government controls its citizens? Through fulfilled promises and actual work? LOL, how else will the few get rich at the expense of the many?

      • A lax regulatory environment and a technology that is outclassed by wind and solar in virtually every single metric except space usage in a country with nothing but space?

        The output of a SMR is heat. That heat can be used to power a steam turbine or it could be used to generate heat directly where heat is needed like industrial or chemical plants. Imagine a SMR that could produce electricity, heat, and desalination in high latitude locations like Alaska. Or a small version could be used at McMurdo Station in the Antarctic during their 24-hour nights. If they could be built into the same form as a 40-foot shipping container, ten of these could be prepositioned around the country to generate power after natural disasters.

        You are thinking of the SL-1?

      • The output of a SMR is heat.

        Heat and, what's that other thing? Oh, yes: radioactive waste. Let's not forget that.

    • Probably nothing, if we're being honest.

    • Nuclear power to provide emission free power for people = something that is at least arguable for

      Nuclear power to power the AI slop machine = screw this bullshit.

      • Re: (Score:2)

        by jsonn ( 792303 )
        At best it is low emission. Preparing all the fissionable material is not exactly emission neutral.
      • There is exactly one scenario where nuclear power makes sense now and that's if you have extreme space constraints and can't just put a wind or solar form up. For everything else you were taking a huge amount of risk, specifically the risk is that billionaire finance bro wanna be tech bro asshats are going to stop paying for the maintenance on those reactors and you're going to have a meltdown. And because these reactors are being proposed to power AI slop data centers they're going to be close to where peo

        • I do not know why old nerds are so obsessed with nuclear power. I know that we are I just don't understand the obsession

          Because in theory, if you do it right, you get nearly infinite free electricity.

          If electricity is cheap enough, it becomes cost effective to turn lead into gold. Artificial diamonds become the cost of crystal. Imagine having diamond glass on your cell phone.

          The "high" cost of electricity limits a lot of cool tech.

          • Re: (Score:1)

            by LIGAFF ( 225383 )

            The claim that nuclear electricity would be "too cheap to meter: is not apocryphal: That's what Lewis L. Strauss, chairman of the U.S. Atomic Energy Commission in 1954, told the National Association of Science Writers in New York in September of that year.

    • Not so clear cut. There are a lot more uses for the power output per square meter from nuclear submarines, satellites and space stations to replacing clean energy in countries where solar exposure is low and heat generation is a bonus.

      Also, power source divercity adds to grid resilience.

      I'm all for renewables but there are genuine challenges in storage and when nature is not playing ball.

      • Re: (Score:2)

        by HiThere ( 15173 )

        I "sort of" agree. But my estimate of this is low enough (cost-including-pollution vs benefits) that I don't think it should be subsidized including being granted favorable legal treatment. In fact I'd be in favor of eliminating bankruptcy protections for any damage it causes.

    • The problem with America is that we don't have the space where it's needed. We have plenty of open land to build these things, but you need a distribution network, and people freak out about the towers and the "radiation." Of course, there are also the people who oppose using the wide open spaces for anything other than wide open spaces.

    • A lax regulatory environment and a technology that is outclassed by wind and solar in virtually every single metric except space usage in a country with nothing but space?

      There was a time when white people thought the whole continent was "nothing but space", except for those pesky Indians. Took care of that problem real nice. Now there are people who complain [counterpunch.org] about solar farms taking up desert space, displacing "the endangered desert tortoise and Joshua trees".

    • You aee kidding right? Wind and solar isn't dependable. The only thing they give are extreme price fluctuations

  • Right (Score:1)

    by Anonymous Coward

    This is the same tub of shit giving socialist handouts to fossil plants https://www.cbsnews.com/news/t... [cbsnews.com]

  • but if it survives in the wake of the incoming trump depression, the company will likely run to a tax haven to profit from the race to the bottom tax rate the trumpistani states are participating in.

  • A fabulous plan with no possible downsides (Score:4, Interesting)

    by JustAnotherOldGuy ( 4145623 ) on Friday June 05, 2026 @11:41PM (#66177660) Journal

    "Just over a year ago, the Trump Administration issued an executive order meant to accelerate the development of nuclear power in the US."

    This sounds like a fabulous plan with no possible downsides, risks, or sharp edges.

    Anyone will tell you that the one thing we need here in the US are lots more loosely-regulated mom-and-pop nuclear reactors with minimal security and oversight.

    • If you want to see sharp edges, build an AI Surveillance Grid and send people's home electric bills to $2000/mo to pay for it.

      Not that the DC government people can be trusted with any of it. Lies and deception are their standard MO on everything now.

    • Re:A fabulous plan with no possible downsides (Score:5, Informative)

      by swillden ( 191260 ) <shawn-ds@willden.org> on Saturday June 06, 2026 @09:08AM (#66177928) Journal

      This sounds like a fabulous plan with no possible downsides, risks, or sharp edges.

      The risks are a lot smaller than you think they are, because of new reactor design. Nearly all of the nuclear reactors in the world are still using a design that's 70 years old, that requires active cooling and doesn't fail safely. We have much better designs now, at least on paper, designs that simply can't melt down, whose failure mode is to simply stop. But no one builds these new designs on industrial scale because they're unproven, and there hasn't been much funding for doing all of the engineering and research needed to develop them into fully-functioning designs that can be.

      I'm skeptical that small reactors are really the best way to actually deploy nuclear power on a large scale, because of security concerns, but starting small is the best way to validate and refine new designs. And modularity is clearly a good strategy for making deployments of varying sizes cost-effective. If you can develop a cost-effective module that can be manufactured in large numbers, you can build large plants by clustering them.

      The new designs shouldn't actually need much operational oversight -- if something goes operationally wrong, they just stop functioning -- but they'll still have highly radioactive cores which, if extracted, could be pretty terrible weapons. Not to make nuclear bombs, but to greatly enhance the damage done by conventional explosives, by adding radiation hazards that linger for years. So, security will remain an important consideration, and the SMRs should only be deployed where security can be assured, which will in practice mean that most are deployed in large clusters.

      This all assumes that the safety, effectiveness and cost-effectiveness of the new designs proves out, of course. The only way to find out whether that will be the case is to try.

      • The risks are a lot smaller than you think they are

        That's good because I think the risks are enormous. Insanely enormous. As in, "enormous enough to completely outweigh the supposed benefits by millions of light-years."

        I'm not worried about them "failing safely", lol, I'm worried about nutjobs blowing them up and releasing crap-tons of toxic, impossible-to-clean-up radioactive shit, dust, and debris, irreversibly contaminating multiple square miles of neighborhoods, cities, water sources, wetlands, etc. etc.

        Thanks for reassuring me that nothing bad will hap

      • Re: (Score:2)

        by AmiMoJo ( 196126 )

        Can you name one of these "can't melt down" designs that is more than just an unproven napkin sketch?

        All the ones I've seen that are at least trying to build a prototype rely on having a cooling pool, meaning they absolutely can melt down if that pool is drained.

        That means you need to protect the entire pool as well as you would protect a traditional reactor, and have an emergency supply of water on hand. So containment buildings, leak proof pools that can survive earthquakes and other natural disasters, al

        • All the ones I've seen that are at least trying to build a prototype rely on having a cooling pool, meaning they absolutely can melt down if that pool is drained.

          Good point.

    • Anyone will tell you that the one thing we need here in the US are lots more loosely-regulated mom-and-pop nuclear reactors with minimal security and oversight.

      So much this.

  • Meanwhile real SMRs are being built (Score:5, Informative)

    by Kernel Kurtz ( 182424 ) on Friday June 05, 2026 @11:58PM (#66177668)
    Here in Canada OPG continues to move along on time and on time and on budget.

    Site construction progress - Spring 2026

    Excavation and blasting of all three major on-site shafts – tunnel boring machine launch shaft, reactor building shaft, and forebay shaft – is now complete. In April, the 2.1 million pound diaphragm plate steel composite basemat – the foundation of the Unit 1 reactor building – was successfully placed 35 metres down into the reactor shaft, allowing for construction on the reactor building to begin moving upwards. A dedicated crane foundation pad is being prepared beside the reactor shaft to support a tower crane which will be used for component installation and material handling activities at the reactor building. At the turbine building, pile installation is nearing completion, while construction of the Administration and Control Buildings remains on track. Construction of the Holt Switching Station continues to progress. This station will transmit electricity generated by Unit 1 to Ontario’s electricity grid until the planned SMR units are connected to the Bowmanville Switching Station. The tunnel boring machine – nicknamed Harriet Brooks - is being assembled ahead of tunneling commencement in support of the Condenser Cooling Water system later this summer.

    https://www.opg.com/projects-s... [opg.com]

    I'll continue to post updates for the haters as construction continues.
    • Is it going to be safe? How do we know?

      • Re: (Score:2)

        by evanh ( 627108 )

        By spending way too much money.

      • Re: (Score:3)

        by Striek ( 1811980 )

        Canada is a world leader in nuclear safety and has been since WWII. And this is Ontario Power Generation. They're no stranger to nuclear power – around half our generation is nuclear.

      • Re: (Score:2)

        by HiThere ( 15173 )

        It's a new model, so the only way to really know whether it's safe or not is to try. But modelling gives VERY useful indications.

      • Is it going to be safe? How do we know?

        We do have a functional regulatory environment here, so I expect it will be as safe as the rest of OPG's nuclear fleet. For people who still worry there is always Xanax.

    • Re: (Score:2)

      by AmiMoJo ( 196126 )

      They are building a BWRX-300, for around $21 billion Canadian. It's a prototype, so high costs are expected I suppose.

      The Office for Nuclear Regulation has some issues with their design too: https://www.onr.org.uk/media/b... [onr.org.uk]

      It's mostly the usual stuff. The control rods aren't proven to be failure proof, and we have seen accidents due to them not inserting, or getting stuck, before. There isn't enough don't to evaluate loss of coolant faults, another known failure mode. While they don't rely on pumps to circ

      • They are building a BWRX-300, for around $21 billion Canadian. It's a prototype, so high costs are expected I suppose......Good luck to them, but it seems very unlikely that it will be economically viable in the end.

        Yes, it is the first of what is expected to be many if it meets expectations. Given OPGs successful track record orther provinces are already expressing interest in their own domestically built nuclear capacity. They have of course done the economic analysis beforehand.

        https://www.opg.com/documents/... [opg.com]

        OPG is a world leader in nuclear power, so no reason to expect this won't be successful like all their other projects. A big part of the first one is establishing the supply chains to be able to cra

        • Re: (Score:3)

          by AmiMoJo ( 196126 )

          Their economic analysis is BS. For example, they discount the cost of "shared" infrastructure, but clearly there is a cost because it has to be built, and scaled to the number of reactors they want to install. At only 300MW each, they will want quite a few of them to make the economics better.

          The increased cost of waste handling and refuelling is not properly accounted for either.

          • Their economic analysis is BS.

            They should have hired you long ago. You could have prevented all that cheap clean power they already manage effectively.

            At only 300MW each, they will want quite a few of them to make the economics better.

            That is the plan, both in Ontario and hopefully by 2050 we have many of them across the country and around the globe.

            The increased cost of waste handling and refuelling is not properly accounted for either.

            We also have lots of uranium and you are clutching at straws. That is another potential supply chain and economic opportunity. OPG also already has 5.5 GW of operating nuclear, so they probably get a good discount :-). As for waste, that is not specific to OPG, but i

            • Re: (Score:2)

              by jsonn ( 792303 )
              Their whitepaper is complete BS. If you can't tell from a single glance, maybe look at it in detail. Let's start with the obvious -- their 4 SMRs is supposed to server 2000 jobs? Doesn't sound like an efficient design to me, unless the S stands for GW size.

            • As for waste, that is not specific to OPG, but it being handled at a national level. All nuclear power (including the SMRs when they come online) have been paying into a fund for this for almost as long as we have had nuclear power, and a site has been selected for our deep geological repository, similar to the one Finland just opened IIRC.

              It's interesting to me and seems odd that there's been a lot of discussion here about "explosions", which are highly unlikely (and have been rare historically), but this seems to be the only mention of nuclear waste, which is a problem that actually exists right now and is only getting worse over time. And a large number of reactors means more sites producing waste, which has to be either stored on site or transported, both of which have their problems.

              As to transportation, we know that trains occasionall

    • Thanks for the update, I was unaware of the project at all.
      Fascinating stuff, I wish them the best & sincerely hope the Canadian government-as-it's-going doesn't see this as a potential source of funds that can be drained off for more norcan.

      • NP. Some of the nutty people here on /. apparently think we are going to just stop halfway and give up (that may be how they roll, but no). The heavy forgings are already done, there is no stopping now. Others figure maybe they did not consider fuel costs and think it will be too expensive to run, LOL as if. The shallowness of the anti-nuclear crowd makes me shake my head. Fortunately they have little sway here, both major political parties support SMRs so political interference is unlikely, and OPG ha

  • Whew. (Score:4, Interesting)

    by dgatwood ( 11270 ) on Saturday June 06, 2026 @12:34AM (#66177684) Homepage Journal

    For a moment, I read that as "supercriticality" and was more than a bit concerned. :-D

    But seriously, that's great — both that it successfully reached that point and that it did so on the first try.

    • For a moment, I read that as "supercriticality" and was more than a bit concerned. :-D

      But seriously, that's great — both that it successfully reached that point and that it did so on the first try.

      Yea, all it means it is producing more neutrons than is lost, so power increases as Moree fission reactions occur over time; a controlled process in nuclear reactors.

  • Nuclear Engineers "Nuclear power scales really well, bigger reactors are cheaper per watt hour"
    Headlines "Small nuclear reactors are new, better scream about them constantly cause they get clicks, if this helps sucker people into useless money holes because hearing about something provably improves the perception of that thing in people's brains regardless of whether the information is good or bad, well that's their problem. Yay ad money!"
    Venture Capitalists and the US and Chinese Governments "I keep hear

    • Re: (Score:3)

      by evanh ( 627108 )

      In reality it isn't for grid power. We're talking something much smaller than SMRs even. And SMRs will never be economical.

      Quote: "..., the company is working with the Department of Defense's Project Pele program for developing a mobile nuclear reactor. The company has also received support from NASA."

      • Re:Oh look the grifters are back (Score:4, Interesting)

        by 0123456 ( 636235 ) on Saturday June 06, 2026 @03:26AM (#66177762)

        Power grids are for high-trust societies. They can't exist for long in a world where you can't rely on some idiot (or some idiotic AI) thousands of miles away to not do something that takes down the entire grid. The lower trust becomes, the smaller a system we can support.

        Localized power is going to be an ever-growing industry over the next few years. We already have multiple companies selling large batteries to power essential home systems during power outages and we're certainly going to see an increase in local power generation to replace grids.

        • Re: (Score:2)

          by evanh ( 627108 )

          Misery is easy. It's happiness we have to work at.

        • Re: (Score:2)

          by pz ( 113803 )

          Distributed power means having 2-3 orders of magnitude more power sources than with centralized systems. That increases the likelihood of an accident by the same factor.

          In the US, we have already had near-disaster level nuclear accidents with about 100 total plants. Let's be generous and say that only one was really bad, TMI. That's a 1% failure rate where "failure" means the potential for disaster-level accident. If you want to remind yourself of what disaster-level accidents look like, recall what hap

          • Re: (Score:2)

            by HiThere ( 15173 )

            The problem is that TMI was NOT a really bad disaster. It was frightening, and could have been bad. Actually, though, it was quite contained. But the more reactors you have, the greater the chance of a really bad disaster. If one of these is small enough to be thrown around by a tornado, you have new possibilities of a really bad disaster. (I didn't check. I assume it's too heavy. But perhaps it could be broken open.)

            OTOH, smaller reactors have a smaller "worst possible case". I'm not really convin

        • Re: (Score:2)

          by PPH ( 736903 )

          Power grids are for high-trust societies.

          True. And the grid is rapidly turning into a low trust environment. While it's true that some of the larger data center operators may be willing to put their money into power resources, many are not. Hoping that they can play the utilities against existing customers and get resources built for free*. So, having these existing customers take their revenue to go off and build their own pounds a stake in the heart of their scam: "We'll be here to buy your power. Trust me, bro."

          *Utilities are basically in the

        • Switching facilities are expensive, but you can design grids such that they are able to break into smaller grids, and that does get continually cheaper. Restarting and synchronizing grids can be difficult, but the more battery storage you've got, the easier that gets. So what we'll more likely wind up with is a grid with more compartmentalization, with a lot of people left in weird and unreliable sectors of the network with unreliable power because nobody will force the providers to actually provide them wi

      • And SMRs will never be economical.

        SMRs that utilize 1950's designs and require intense operational oversight and maintenance could never be economical. SMRs that use better, safer designs that can safely operate with no active operational oversight and little or no maintenance, which can function without intervention and without refueling for 20-30 years, then be inexpensively disposed-of and replaced, and which can be manufactured in large quantities to bring the unit cost down, promise to be very economical.

        Will the new designs actuall

      • Quote: "..., the company is working with the Department of Defense's Project Pele program for developing a mobile nuclear reactor."

        Pele is the Hawaiian goddess of volcanoes and fire [wikipedia.org]. Who came up with that name? Seems to be tempting fate. Maybe someone out there really likes volcanoes.

    • Re: (Score:2)

      by gweihir ( 88907 )

      Yes. Also remember that even really large nuclear reactors are not economically viable these days. Small ones will probably perform on the level of LLMs, i.e. some years until stupid investor money dries up and then total crash.

  • Maybe. Or not. That they reach this early milestone now just shows how disconnected the whole idea of fixing current problems with it is. Obviously, this test says nothing about economic viability and nuclear never had that. Even less so today.

  • Interesting design (Score:4, Informative)

    by Registered Coward v2 ( 447531 ) on Saturday June 06, 2026 @07:35AM (#66177870)
    From Antares' website, this appears to be a non-refuelable low power (100KWe -1MWe for 6+ years) reactor. The fuel design is not a new concept, pebble bead reactor designs have been for a while, and China appears to be working on one as well. The fuel design does have some advantages, such as online refueling, the ability to withstand the heat generated by the fission reaction without cooling, and in some designs the ability to disperse the fuel to shutdown the reactor. One challenge for earlier designs was the use of helium as a heat transfer medium which was hard to top from leaking past pump seals, etc. This design uses sodium/N2 loops, avoiding issues with helium. From their website, it appears they do not plan to scale it for utility use but focus on markets for small portable power that are not as cost sensitive, such as portable power for military use.

    • Re: (Score:2)

      by AmiMoJo ( 196126 )

      Sodium is a rather nasty medium to use as coolant. It corrodes, and spontaneously catches fire on contact with air. Attempts have been made in the past, ending in expensive failures.

      • Sodium is a rather nasty medium to use as coolant. It corrodes, and spontaneously catches fire on contact with air. Attempts have been made in the past, ending in expensive failures.

        Yea, although given the reactor lifespan is listed as 6+ years, I wonder how much corrosion will occur. Clearly, preventing any leakage is key to avoiding unpleasant results.

  • The expensive way.

  • If you are down wind and next to the generation facility you get free power. Upwind and 20 miles away you pay full price. Then figure out the in between fees.

    If you are exposed to higher risk you should pay less.

    • If you are down wind and next to the generation facility you get free power. Upwind and 20 miles away you pay full price. Then figure out the in between fees.

      If you are exposed to higher risk you should pay less.

      Not a bad idea, do it or all - coal, gas, solar, wind...

Slashdot Top Deals

The brain is a wonderful organ; it starts working the moment you get up in the morning, and does not stop until you get to work.

Close