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U.S. Reviewing Proposed Design of Miniaturized Nuclear Power Plant
- mmaunder 10y agoNuclear reactors have been used on submarines for decades. McMurdo base in Antarctica was powered by a nuclear reactor for 10 years which ended in the 70s.
- privong 10y ago> McMurdo base in Antarctica was powered by a nuclear reactor for 10 years which ended in the 70s. Yes, but I'm not sure that was an overwhelmingly positive example supporting increased use of widespread reactors: https://en.wikipedia.org/wiki/McMurdo_Station#Nuclear_power_1962.E2.80.931972 https://en.wikipedia.org/wiki/McMurdo_Station#Nuclear_power_... As a result of continuing safety issues (hairline cracks in the reactor and water leaks), the U.S. Navy Nuclear Power Program decommissioned the plant in 1972. Or course, one would hope that more modern design would be safer.
- tyingq 10y agoFor comparison, the reactor described here outputs 50 megawatts, and is 15 feet in diameter and 76 feet long (~54,000 cubic feet). The S6G reactor in Los Angeles class submarines outputs 150 megawatts and is 33 feet in diameter and 42 feet long (~144,000 cubic feet).
- microcolonel 10y agoThe newer revision outputs 165MW, apparently.
- tbihl 10y agoSo, I'm calculating a material buckling for S6G that's only one-fourth that of the described SMR, and I know S6G is highly enriched. Why is the SMR so close to parity for power density, especially if it's using natural circulation?
- tbihl 10y agoI would have said geometric buckling above.
- ci5er 10y agoI'm getting bleary eyed from a day that has gone on too long, but how does something approximately 33x33x42 feet equal 140k ft^3? Same question with the first one too. The cubic-feet measurement is including something else, right? What might that be?
- tyingq 10y agoOops...thanks for the catch. Used diameter instead of radius when calculating the volume of each cylindrical object. So, the cubic footage is off...but for both. So, corrected: For comparison, the reactor described here outputs 50 megawatts, and is 15 feet in diameter and 76 feet long (~13,500 cubic feet). The S6G reactor in Los Angeles class submarines outputs 150 megawatts and is 33 feet in diameter and 42 feet long (~35,000 cubic feet).
- ci5er 10y agoYeah -- I figured that out after I caught a little shut-eye. If my brain had been operating at all, I would have seen that and not even asked. Sorry.
- acidburnNSA 10y agoThere was also one powering a US Army ice base in Greenland called Camp Century. The video of it is actually pretty awesome [1]. [1] https://www.youtube.com/watch?v=1Ujx_pND9wg https://www.youtube.com/watch?v=1Ujx_pND9wg
- throwaway7645 10y ago50 MW is small for all the red-tape necessary to operate a nuke plant. 1500 MW is nice if you're going to need over 1,000 staff. I'm not sure how much headcount they could eliminate with a better design.
- ethbro 10y agoI'm assuming the plan is that a 15x50MW install isn't going to use 15x the 1x50 personnel and site prep. Otherwise there'd be no way they're viable except for smaller requirement installs.
- privong 10y agoIt sounds like a neat idea, and potentially safer(?). But I don't understand why they're claiming it'll be cheaper: > But one company thinks that by going smaller, they could actually make nuclear power more affordable. And later in the article: > The company believes that 570-MW project can be completed for less than $3 billion. By comparison, a new 1,150-MW reactor at Watts Bar in Tennessee cost around $4.7 billion and began operation in 2016 after years of delays. Based on those numbers, the construction cost of the modular reactor system is almost 30% more expensive per MW. Are they anticipating the operational costs to be lower, thus saving money in the long run? But the article claims they're trying to save on the construction costs: > Companies such as NuScale hope to offset the higher costs by saving on the cost of construction Which isn't true, based on the numbers the article quotes. On a related note, I wonder if refueling these modular would be more difficult/costly because of their smaller size and the submersion design?
- maxerickson 10y agoThe savings would likely kick in as they manufactured more and more of the vessels.
- privong 10y ago> The savings would likely kick in as they manufactured more and more of the vessels. Maybe, but I would have thought that would have either factored that into the quoted cost estimates, or that they would have said something like "and similar future plants would cost X". (where X is lower).
- Bluestrike2 10y agoThose cost savings won't be immediate, and will likely have to wait until production facilities are expanded once there are sufficient orders to warrant it. And not just immediate orders, but ones for a few years out as well.
- privong 10y ago
- tyingq 10y agoNot sure if I've got apples to apples here, but... This thing fits on the back of a semi truck, and is supposed to be 50 megawatts capable. The Hooper solar power plant in Colorado's San Luis valley is also 50 megawatt, and spans 320 acres. Edit: Well, apples to apples for actual "energy density" vs photo voltaic cells. Not making a statement about which is better either...just an interesting comparison.
- maxerickson 10y agoNo, the transport size of the reactor isn't the apple. It would need other equipment to operate. Here they do say ~90 acres for 1 GW (I read 0.14 sq mi in the thumbnail, the video doesn't load), so still vastly less area than solar: http://www.nuscalepower.com/why-smr/environmental-footprint http://www.nuscalepower.com/why-smr/environmental-footprint They probably don't scale down well though (like if some of the area is setback).
- jessriedel 10y agoNuclear power plants have very large "clearing areas" for safety and security reasons. In fact, one of the reasons Elon Musks cites for investing in solar rather than nuclear power is that the power area density is actually comparable. Here's some criticism of that claim, but it agrees that it's within about an order of magnitude (which is impressive given that nuclear is probably dozens of orders of magnitude denser in power at the scale of the reactor). https://carboncounter.wordpress.com/2015/07/13/a-book-recommendation-for-elon-musk/ https://carboncounter.wordpress.com/2015/07/13/a-book-recomm...
- masklinn 10y agotyingq lists Hooper at 50MW/320 acres, or 156kW/acre. The Paluel nuclear plant is 5200MW (4x1300MWe reactors) over 400 acres ("160 hectares" according to https://www.edf.fr/groupe-edf/producteur-industriel/carte-des-implantations/centrale-nucleaire-de-paluel/presentation https://www.edf.fr/groupe-edf/producteur-industriel/carte-de...), or 1300kW/acre, so it's within an order of magnitude yes. As long as we only consider nameplate capacity and ignore capacity factor of course, which greatly favours solar as it has a much lower capacity factor than nuclear. If you factor that in the difference grows by ~4x (PV in dry southern US states has a capacity factor of ~20%, US nuclear plants are around 90%).
- castratikron 10y agoI wonder how the energy density of one of these compares to a traditional reactor. That's what I would intuitively correlate with safety. Solar and wind, for example, are very safe mainly because they has such a low energy density.
- sandworm101 10y agoSafety is in the eye of the beholder. Turbines do fail, sometimes with fire and explosions. When so spread outt, hundreds of turbines, forest fire is a risk. A nuke plant, being smaller, can be better covered by safety systems than an expansive wind farm. But the practical differences between the two techs are so great that direct comparison is probably pointless imho.
- obelix150 10y agoThis was described in depth in a recent Nova program called "The Nuclear Option"[1][2]. In it they referenced multiple other more safe methods than the most common type of reactors in use today which use technology designed decades ago. Sodium based reactors were new to me entirely and appear much more safe than existing designs, also capable of using depleted uranium. Note: I'm not a nuke supporter just a curious guy. [1]: http://www.pbs.org/wgbh/nova/tech/the-nuclear-option.html http://www.pbs.org/wgbh/nova/tech/the-nuclear-option.html [2]: http://www.pbs.org/video/2365930275/ http://www.pbs.org/video/2365930275/
- acidburnNSA 10y agoI watched it too and can elaborate a bit on this since I'm in the SFR business (anyone want one?). When an nucleus fissions, not all the heat comes out at once. Roughly 7% of the energy comes out later, distributed in time as a decaying exponential [1]. The really key safety challenge of nuclear is cooling that after the chain reaction is stopped (because 7% of 3 billion Watts is 210,000,000 Watts). So if the power goes out (like in Fukushima), traditional plants rely on active cooling systems like diesel generators, fuel cells, steam turbines, etc. to run pumps that cool the fuel, preventing the fission products from emerging. There are some nuclear reactors that can handle the decay heat without active cooling systems. They're mostly low-pressure/exotic coolant systems, including liquid sodium metal, molten salt (FLiBe, NaCl, etc.), molten lead, etc. These can just naturally circulate and dump heat thorough ambient heat exchangers outside. And some gas-cooled Pebble Bed reactors can do it too because their fuel can get hot enough to just conduct it out. Worldwide, we have by far the most experience with sodium-cooled fast reactors (400 reactor-years). As pointed out in NOVA, two weeks before Chernobyl, the small sodium-cooled EBR-II in Idaho demonstrated station blackout conditions without scram and it just shut itself down and cooled itself. But sodium metal has a problem. It is quite reactive with air and water, so dealing with it can be an operational challenge. We know how to deal with sodium leaks in sodium-water steam generators (arguably the most "exciting" component in a SFR) and sodium fires, but they can still be expensive. The French SuperPhenix SFR suffered a series of political and weather-related challenges that ended up giving it a terrible operational record. The Japanese SFR Monju has a bad history too with some 10 year outages and whatnot. But EBR-II and FFTF in the US operated fantastically until Bill Clinton finished shutting down their funding following the long slowdown of nuclear research that came after the failed and super-expensive Clinch River Breeder Reactor Project, and the Russians now have the best and only commercial SFRs. So there's still hope for SFRs as Gen IV nukes. The French are working on a huge program called ASTRID to make a better SFR. The Koreans have KALIMER/PGSFR that's very far along in design. The US has TerraPower's Traveling Wave SFR, the Indians are turning a big one on now, China is operating a sodium-cooled test reactor (CEFR). The Russians are building another awesome SFR test reactor (MBIR, to replace BOR-60) and continue to operate and sell their BN-600/800, etc. series power plants. [1] https://whatisnuclear.com/physics/decay_heat.html https://whatisnuclear.com/physics/decay_heat.html
- Gargoyle 10y agoHow does this compare to what the Y Combinator backed UPower is doing?
- acidburnNSA 10y agoI believe UPower reactors (no renamed to Oklo after the spontaneous chain reactions that occurred in Africa 2 billion years ago) are even smaller. My guess from the rename is that they want to make shippable modules that are entirely self-contained, i.e. you just set it down and plug stuff in. Could be useful in very distributed markets. NuScale can ship lots of parts but you still have to build out a big site.
- avar 10y agoUPower is making a nuclear thermal battery, not a nuclear fission reactor.
- intrasight 10y agoWith current and foreseeable low cost of natural gas in the USA, nuclear tech will never be economically competitive. In addition, the nuclear industry asks the government to legislate liability caps.
- ajkjk 10y agoHow do you know?
- intrasight 10y agoJust stating an educated opinion
- ajkjk 10y agoOkay, I don't believe you. How do you know?
- tmuir 10y agoIs the foreseeable future greater than 16 years? In 2001, the entire energy sector looked unrecognizable when compared to 2017.
- intrasight 10y agoForeseeable until something changes. Utility companies are making long-term capital expenditure bets in a uncertain political and economic environment. If they can get cheap gas and cheap gas turbines, why would they consider risky, expensive, unproven technologies?
- beders 10y agoWhy? This is pure lobbyism. There is a cheaper, safer and abundant alternative. Solar energy. Just do it already.
- parineum 10y agoFor baseline load?
- dmix 10y ago> McGough says the company envisions the modules also could be used in other ways. For example, he says, they could be installed near wind turbines as backup when the wind isn't blowing. Or they could be used by the military to power bases that need electricity even if the grid goes down. About a dozen clients in the U.S. and abroad are looking at the technology, he says.
- beders 10y agoRenewables is the way to go. No waste problem, vastly reduced risk. Why bother with this?
- deleted 10y ago[deleted]
- microDude 10y agoI have seen this company slowly mature over my past 6 years living in Corvallis, Oregon (original location for NuScale). I was excited when I first saw the design and started to look at employment opportunities at the company. At the time, they only were looking for experienced engineers (15+ years) with knowledge of the Nuclear Regulation Commission (NRC). Even after 6 years, they just now have submitted the application to NRC. It is depressing how much Nuclear has been over-regulated.
- azinman2 10y agoWhat makes you think it's more than necessary given the consequences?
- striking 10y agoI think it might be easier to answer that question if you outline which consequences you're most concerned about.
- beders 10y agoA single accident can kill thousands, cause cancer for several hundred thousands more, cost billions of dollars in clean up usually tax payers pay for, nuclear plants have no concept of proper disposing and dismantling a reactor, have byproducts with unacceptable half lives, are potential targets for terror threats, use other harmful chemicals (people like to ignore) etc. etc. etc.
- Natsu 10y agoChernobyl-style reactors are a thing of the past, modern ones don't do all that. Even Fukushima didn't kill anyone, just some contamination that will cause some statistical level of cancer increase.
- tcbawo 10y agoThe long time horizon to recover from any disaster is scary. Chernobyl (clearly inadequate safety planning) aside, is there any reason to believe that a Fukushima-type disaster would not be possible (or inevitable)?
- Animats 10y agoThere are lots of small and medium sized reactor schemes.[1] As of 2014, there were four from the US alone, and 36 worldwide. Nuscale is covered starting at page 80 of that study. NuScale wants to operate their reactor modules in a water pool, with all the reactors at a site sharing the same pool. If anything goes seriously wrong with one unit, the pool gets contaminated. Then all the units, and the spent fuel pool, are inaccessible, and repair becomes a huge problem. The only reason NuScale is supposed to be cheaper is optimistic safety assumptions. "The NuScale Emergency Planning Zone (EPZ) is expected to be as near as the site boundary rather than the current 10 miles required by large traditional plants in the U.S." - IAEA. NuScale's design focuses on emergency core cooling, with their water pool approach. But other things can go wrong. Such as leaks. There's a long history of nuclear reactor leaks. [1] https://www.iaea.org/NuclearPower/Downloadable/SMR/files/IAEA_SMR_Booklet_2014.pdf https://www.iaea.org/NuclearPower/Downloadable/SMR/files/IAE...
- sandworm101 10y agoInstalling partitions in the pool to isolate each reactor should be a very minor expense. They need not even be self-supporting, just watertight enough to prevent mixing. Builing a larger or more partitioned pool shouldnt even enter into the cost equation imho. Water and concrete are rather cheap given the context.
- nine_k 10y agoDraining one section becomes problematic if walls cannot support the weight of the water.
- Animats 10y agoCompare the Babcock and Wilcox (now BWXT) design in the same document. They have a full large containment building around each reactor. If you have a full, large containment structure, serious reactor troubles at the meltdown level are expensive, like Three Mile Island, but not disasters, like Fukushima. At Fukushima, the containment on the plant was a small vessel around the reactor vessel, like NuScale, and it wasn't able to contain the meltdown. NuScale's design assumes there will never be a meltdown.
- beders 10y agoStop looking at nuclear. (Maybe read up on the nuclear disasters so far and think about that when they install a nuclear power plant in your neighborhood...) Also, again, why bother? https://www.greentechmedia.com/articles/read/how-much-renewable-potential-does-the-u.s.-have https://www.greentechmedia.com/articles/read/how-much-renewa... Vote this down all you like, it doesn't change the facts.
- blisterpeanuts 10y agoThe renewables vs. fossil vs. nuclear issues have been debated extensively over the decades. There are two game changers today: fracking and lower-cost solar. Fracking has totally changed the equation. Natural gas has blown away oil and coal in power generation, and solar (when combined with the federal tax incentive) is finally becoming competitive with traditional utilities. Nuclear is appealing for various reasons, mainly the avoidance of combustion and carbon release, and also the technology has advanced greatly since its heyday in the '70s. Pebble reactors, micro reactors, better waste processing are compelling reasons to consider a renewed push into nuclear. But as more residences and commercial buildings adopt solar, and fracked gas (plus vast new gas field discoveries in the Mediterranean and elsewhere) continues to be extremely available and competitive, nuclear looks increasingly like an also-ran. Still, nuclear has a great future in orbital and interplanetary spacecraft, where miniaturization and reliability are paramount, and safety and affordability are secondary (just locate the nuclear plant at the tail end of the ship behind a few feet of shielding).
- ci5er 10y agoAlso, we have a pretty good idea how far we can practically, economically, push things like solar/wind, IF storage is worked out. The processes of converting photons and wind into electron potential are well understood - it's just math. But, with storage - renewable power is still never going to be "free-ish". More cost-effective than burning hydrocarbons, maybe, but cheaper is not "free". What if we could bootstrap our way to free-ish? To do so, we'd have to develop the technology further than it has been developed so far today - and that's an evolutionary process. It would take decades of sustained R&D. But, the carrot is huge -- one benefit would be that we'd never have to worry about fresh water - anywhere - ever again. Nuclear, then nuclear++, then nuclear+++ offers us this hope, to a degree that renewables do not.
- pfarnsworth 10y agoAre thorium plants not viable? I remember hearing so much about them, but nothing ever happened, it seems.
- blisterpeanuts 10y agoThe Wikipedia article[1] on thorium reactors lists the following disadvantages (quoted from the article): - Breeding in a thermal neutron spectrum is slow and requires extensive reprocessing. The feasibility of reprocessing is still open. - Significant and expensive testing, analysis and licensing work is first required, requiring business and government support. According to a 2012 report by the Bulletin of the Atomic Scientists, about using thorium fuel with existing water-cooled reactors, it would "require too great an investment and provide no clear payoff," noting that "from the utilities’ point of view, the only legitimate driver capable of motivating pursuit of thorium is economics." - There is a higher cost of fuel fabrication and reprocessing than in plants using traditional solid fuel rods. - Thorium, when being irradiated for use in reactors, will make uranium-232, which is very dangerous due to the gamma rays it emits. This irradiation process may be altered slightly by removing protactinium-233. The irradiation would then make uranium-233 in lieu of uranium-232, which can be used in nuclear weapons to make thorium into a dual purpose fuel. /end quote I do wonder whether some of these issues are significantly different from the problems of uranium fission reactors. The benefits of thorium are huge: can't be used to produce nuclear bomb material; easier to prevent meltdowns; enrichment of fuel not needed. [1] https://en.wikipedia.org/wiki/Thorium-based_nuclear_power#Possible_disadvantages https://en.wikipedia.org/wiki/Thorium-based_nuclear_power#Po...
- WhitneyLand 10y agoWhen you spend 5 Billion on a reactor how does the cost break down? R&D, construction, permitting and regulatory? It's hard to understand why it can't be done less expensively without big safety compromises.
- acidburnNSA 10y agoDepends on the reactor, but very roughly: $500M on R&D $3000M on construction $1500M on permitting and regulatory Construction delays and supply chain issues have been known to bring construction costs way up.
- ChuckMcM 10y ago"NuScale is already partnering with a consortium of Utah utilities to build a 12-module power plant on land in Idaho owned by the U.S. Department of Energy." -- I wonder if they would run all the wires over the border to a giant data center right there on some DoD owned land. :-) [1] The TRIGA reactors are similar [2] although much smaller. I'm surprised they would share a pool though I'd think having them in separate pools would provide both better encapsulation if something was to go wrong and easier maintenance and disposal. [1] Actually the NSA's data center is south of the Great Salt Lake so it would be a fairly long run of wires for that. [2] http://www.ga.com/triga http://www.ga.com/triga
- maverick_iceman 10y agoI'm pessimistic that this proposal will go very far in the face of sustained opposition by groups like Greenpeace or Sierra Club. Another tragic remainder of the harm caused by undereducated misdirected environmental activism.
- ohnotthatguy 10y agoYou all have heard that we can harness energy from the light of the sun and convert it into electricity[1] with the risk of contaminating the environment which sustains us[2] coming only from the production of the tools to harness that energy from light, right? Aside from the context of space travel beyond where collecting this underutilized resource, "Light From Stars" is viable, why is this even a conversation? [1] https://en.wikipedia.org/wiki/Solar_power https://en.wikipedia.org/wiki/Solar_power [2] https://en.wikipedia.org/wiki/Lists_of_nuclear_disasters_and_radioactive_incidents https://en.wikipedia.org/wiki/Lists_of_nuclear_disasters_and...