25 ms·

"The SMR’s 12 modules, each producing 50 megawatts" So each module is a little smaller than the reactor of the 1960's era submarine I served on and is based on

• ksidudwbw 4y ago
  And that reactor has also tested and proven reliability. Quirks have been evened out
  • deleted 4y ago
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  • mwattsun 4y ago
    We never had a single problem with it in the years I was on board. There were few moving parts besides the control rods and a few valves. When I stood watch on the steam throttle the reactor power would spike when I opened the throttle up. I tell my kids I've controlled a nuclear chain reaction with my bare hands.
    • omginternets 4y ago
      How long did you serve? When you say "never had a single problem", are you being literal? I'm abstractly aware that nuclear technology is reliable, but your anecdote somehow makes it more relatable. You've piqued my curiosity :)
      • lnsru 4y ago
        I really don’t understand this reliability question. There was Fukushima and Chernobyl in my lifetime. Fukushima got earthquake and tsunami at the same time. Shit happens. I have no opinion about Chernobyl since it was in a country with extremely poor working culture. But otherwise in my opinion nuclear power plant is just another piece of big machinery. Comparable to semiconductor fab. They have there enough of interesting gases to gas whole population of the next city. But it never happened yet.
        • sitkack 4y ago
          • MichaelCollins 4y ago
            The crew running the reactor during the accident were poorly trained, poorly managed, and weren't comfortable pushing back against bad management. There is no doubt that Chernobyl had a poor work culture, a rot that came from the top but nevertheless permeated the whole facility.
            • ncmncm 4y ago
              The person most personally responsible went on to manage another, similar system. Management failings are part of the risk profile of any hazardous technology, from nukes to feedlot pig farming. Leaving them out produces dishonest numbers.
              • MichaelCollins 4y ago
                What are you responding to? I am responding to a claim that acknowledging poor work culture at Chernobyl is bigotry. It's not bigotry (an intolerance of others) nor is it even prejudice (judging before you have the relevant facts.) It's a widely acknowledged historic fact that Chernobyl had a terrible workplace culture. If you want to criticize somebody for ignoring Chernobyl's workplace culture, then you should have responded to sitkack, who seems to think that people shouldn't talk about this aspect of the disaster.
      • mwattsun 4y ago
        I was on the sub for three years. I am not aware that we had any incidents with the reactor. We had a pipe break and start to flood the sub, but that wasn't nuclear related. In the shipyard we had an incident where the neutron detector pegged high but it was determined to be caused by TIG welding. https://www.twi-global.com/technical-knowledge/job-knowledge/tungsten-inert-gas-tig-or-gta-welding-006 https://www.twi-global.com/technical-knowledge/job-knowledge...
        • omginternets 4y ago
          >We had a pipe break and start to flood the sub, but that wasn't nuclear related. That sounds absolutely terrifying. How did you guys end up fixing it? >In the shipyard we had an incident where the neutron detector pegged high but it was determined to be caused by TIG welding. Neat! :)
          • mwattsun 4y ago
            People on submarines tend to know the systems they are responsible for very well since their life may depend on it. In this case they knew which valves to turn to stop the flow.
• titzer 4y ago
  I've had friends that served on nuke subs. It still blows my mind that a sub only needs to refuel once every 15 years. I never understood the argument nuclear power is so "dangerous". The US navy has fielded nuclear reactors in warzones since 1954 and no Chernobyl. Almost the entire fleet is nuclear-powered, including all aircraft carriers, subs, and battleships.
  • chihuahua 4y ago
    I agree in principle, but I am not aware of any nuclear powered battleships. Iowa class BBs have steam turbines running on fuel oil.
    • frozenport 4y ago
      aircraft carriers?
      • MichaelCollins 4y ago
        All of America's supercarriers have been nuclear powered since the USS Kitty Hawk was decommissioned in 2009. But if you include "amphibious assault ships" like the Wasp class, which can carry a lot of helicopters and STOVL airplanes like the F-35B and Harrier, then US Navy still has a lot of conventional powered carriers.
    • squidlogic 4y ago
      Correct me if I’m wrong haven’t Iowa class battleships all been decommissioned sometime in the early 1990s?
      • jasonwatkinspdx 4y ago
        Yes, and it was a colossal waste of money keeping them running even that long. Realistically they should have been scrapped in the period after the Korean war.
        • 4y ago
• danans 4y ago
  > I could never understand why we didn't build these for civilian use (cost I figured) If Nuscale can hit their LCOE goal of $65/mWh by 2030, they will still be 2-3x the LCOE of Solar+storage today [1] (which will only get cheaper). In the long term both technologies will play an important role, but the zero carbon technology we can deploy at scale today is the technology we need today. 1. https://www.lazard.com/perspective/levelized-cost-of-energy-levelized-cost-of-storage-and-levelized-cost-of-hydrogen/ https://www.lazard.com/perspective/levelized-cost-of-energy-...
  • scythe 4y ago
    It appears that the LCOE for utility-scale solar which you're referencing here, community and rooftop both being significantly more expensive, is based on existing installations. But existing installations would have used the cheapest available land, and the cheapest available land tends to be in short supply. Solar installations on a significantly larger scale would have to use less ideal land (less accessible, more rugged, more expensive) and would incur associated cost increases. Solar is like a huge orange tree where we have been mostly picking from the lower branches — there are more than enough oranges on the tree for everyone, but you can't expect them all to be as easy as the low-hanging fruit. However, I am optimistic about storage, particularly since zinc-bromine seems poised to break into the market, with excellent resource availability. Zinc production is about 13 Mt/yr [1], and the battery offers about 67 Wh/kg, with ~1/3 the weight in zinc, so 200 Wh/(kg Zn), so potential production is over 1 TWh/year before running into availability problems. There are also about half a billion tonnes of bromine in the Dead Sea alone [2]. (Since this is my third Zn-Br post, I'll add that I don't currently have investments in them, but I'm considering it.) 1: https://en.wikipedia.org/wiki/Zinc#Production https://en.wikipedia.org/wiki/Zinc#Production 2: https://en.wikipedia.org/wiki/Bromine#Occurrence_and_production https://en.wikipedia.org/wiki/Bromine#Occurrence_and_product...
    • pfdietz 4y ago
      There is an enormous amount of cheap land, globally. Any land that is cheap enough for farming is cheap enough for PV, and land that isn't even adequate for farming tends to be even cheaper than that.
• c3534l 4y ago
  This makes me think the navy now has something better, so they're loosening the reigns on last-gen nuclear technology.
• jasonwatkinspdx 4y ago
  Military reactors run on very highly enriched fuel, nearly weapons grade. That dramatically increases proliferation concerns when you're talking about large fleets of civilian reactors. I'm rooting for NuScale, but so far every attempt at realizing the SMR dream has failed, so I'd caution people about thinking this is a pure slam dunk and it's just some sort of mass stupidity keeping the technology back.
  • shepherdjerred 4y ago
    What danger is there with proliferation? Does it really matter when the US has thousands of nuclear weapons?
    • nsxwolf 4y ago
      Yeah I never quite got this. We can have Putin say “you’d better let me kill whoever I want or I’ll destroy the entire world”, but we can’t have power plants.
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        [deleted]
    • apendleton 4y ago
      Obviously a very US-oriented perspective, but: yes, to the extent that the US has historically attempted at least sometimes to be a global police power, they're significantly constrained when the country they're trying to police has nuclear weapons. The US response to Russia invading Ukraine has been fundamentally different in kind from, say, Iraq invading Kuwait, in which Iraqi forces were pushed back to the border in a matter of days. There are lots of reasons for this (much greater asymmetry in conventional military forces, etc.), but at least in part this is because of US concerns that direct conflict with Russia would escalate to nuclear war. Similarly, can already start to see how US posture towards North Korea is starting to change and will likely continue to do so as a result of their nuclear advancement.
      • 4y ago
• samstave 4y ago
  • worik 4y ago
    Ouch, so shouty. IMO the future of energy is decentralisation not centralisation. One of the reasons I do not think nuclear fits. It is impossible to handle nuclear in anything other than huge establishments (I feel this proposal for mas produced nuclear plants is going to end in tears). The future is local.
• petre 4y ago
  > I could never understand why we didn't build these for civilian use Because they use enriched uranium, 30% compared to ~7% in LEU which is used in civilian power plants. It's seen as a proliferation risk. And big reactors are more efficient. The problem is they cost a lot and have always had cost overruns. The reactor vessel has to be comissioned for building and rach one is esentially a prototype build to specs. There were even cases were the reactor vessel was defective and had to be scrapped. Building a larger fleet of smaller reactors in production facility with QA could bring these costs down and enhance safety. The NuScale design will use >5% LEU with a 24 month refuelling cycle. At least we won't have to shut down an 1000 MWe reactor for refuelling every 2-3 years. We shall see. The US now has an equilavent to China's Belt and Road initiative, caled PGII, that it will use to finance infrastructure projects in developing contries. There are plans to build a 6 reactor NuScale plant in Eastern Europe with studies financed through this project. https://www.state.gov/united-states-takes-next-step-in-supporting-innovative-clean-nuclear-technology-in-europe/ https://www.state.gov/united-states-takes-next-step-in-suppo...
• AnonymousPlanet 4y ago
  > I could never understand why we didn't build these for civilian use (cost I figured) but now we will Is there a single small nuclear reactor of this kind that has ever been successfully dismantled? As far as I know, all small nuclear reactors that have ever been used by any navy are still in storage somewhere [1] until someone figures out how to get rid of them properly. Maybe that's one of the reasons why they aren't common in civilian use. [1] Well, except for those still in use or on the ground of the ocean somewhere.