The NNL and small SMR’s

The National Nuclear Laboratory have produced another of their position papers, which addresses the topic of Small Modular Reactors. The report, like their previous one on Thorium, its bit low on detail (again it seems to be a case of them saying “trust us we wear white coats and tinker with nuke stuff, we went to Oxford/Cambridge, play croquet and smoke a pipe, we know what we’re talking about”), but it is interesting to see how their conclusions are not that far removed from my own conclusions regarding small reactors (see Part 10 here).

As I pointed out before, the major advantages of SMR’s (again we’re defining “small” on the basis that’s its significantly less that 1 GW+ “Mega” units currently favoured) are the “niche” roles they can fulfill. Smaller nations who would otherwise struggle to build a single “Mega” reactor can finance and commission a SMR type reactor reasonably quickly (the NNL report suggests 6 years for a larger plant and 3 years for an SMR). Such smaller plants can also be build in places unsuitable for a larger plant.

Some SMR designs can also perform certain specific again “niche” roles. The NNL specifically highlights the concept of using small Fast Neutron Reactors to dispose of nuclear waste, notably the proposed S-PRISM reactors BNFL wants to build at Sellafield. I would note my skepticism both of Fast Reactors (as I’ve discussed with reference to the S-PRISM before) as well as the notion that such disposal methods are economically viable (as I discuss in this comment string, numerous reports suggest that immobilization followed by deep geological storage is both cheaper and probably safer too).

But either way we re talking about a niche market, a handful of a reactors. One or two S-PRISM reactors could easily do the job (and I mean literally one or maybe two of them). The power output to the grid would be minimal and given the high costs of such reactors, its unlikely to be economically viable (any electricity generation is essentially a sort of “bonus” on top of what is essentially a non-proliferation exercise).

Indeed it is here that both I and the NNL seem to be in agreement, the purpose of these reactors is to reach the part other reactors can’t reach. Inevitably by sacrificing economies of scale these SMR’s will be more expensive to build (per GW) and operate (on a LCOE scale) compared to “Mega” LWR’s. Thus any nuclear cheerleaders arguing that such reactors will somehow magically bring down the costs of nuclear electricity are likely to be disappointed. This in particular applies to any new Generation IV designs, as they will inevitably prove to be harder and more expensive to build (at least in the short term) than LWR’s. Equally while we can build an individual SMR reactor more quickly than a much large plant (naturally!) the GW/year roll rate will be lower, not higher. While the NNL’s report is low on detail on these issues (again, they’re from Cambridge and they smoke pipes!), I do go into detail in these issues in my section on SMR’s (again see part 10).

A good example of such a small modular LW reactor is the Babcock & Wilcox 125 MW Mpower reactor [Credit: Babcock & Wilcox]

Mention LFTR’s

The cheerleaders of the LFTR ignored the NNL’s previous report on Thorium (see some of the sort of comments they typically make in this discussion string here), because they argued, it did not address the use of LFTR’s (actually a pro-nuclear colleague of mine pointed out it the NNL did discuss the benefits of a complete Thorium breeding cycle, but then pointed out it was a few decades away). I would note that the head of the NNL Paul Howarth does discuss LFTR’s here. Either way the NNL specifically mention LFTR’s in the SMR report. They don’t say a lot (pipes, Oxford, etc!) but then again I suppose there’s not a lot to say, as only a handful of research units are seriously working on the idea and most of the concepts they are considering are entirely theoretical.

I would note that the NNL report does also mention Weinberg and they point out his major objection with the “Mega” LWR was more the “Mega” part of the equation rather than the “LWR” part of the equation (or one assumes the “Uranium” part if you read what the NNL says about Thorium). While the NNL report does dance around the safety issue (as nuclear supporters often do), as I pointed out (both here on SMR’s and here with regard to LWR’s) and as Richard Black of the BBC addresses (again citing Weinberg) smaller reactors will generally produce safer and more versatile reactors. But there is a price premium to be paid for such reactors and ultimately the amount of any country’s electricity (or overall energy) than can be supplied by such reactors (once we factor in practical real world issues) is significantly smaller than with the “Mega” LWR paradigm. Its a simple choice between quality or quantity.

But certainly if there’s one point both I and the NNL are in agreement on, it is that SMR’s do not help solve the any of the key red line issues for nuclear power. Notably lowering the cost, increasing the build rate not to mention overcoming the practical limits to how much nuclear capacity any grid can support. Indeed, SMR’s will likely have the opposite effect (be more expensive and less GW/yr installed).

About daryan12

Engineer, expertise: Energy, Sustainablity, Computer Aided Engineering, Renewables technology
This entry was posted in clean energy, economics, energy, LFTR, nuclear, politics, power, renewables, sustainability, sustainable, thorium, Uncategorized. Bookmark the permalink.

10 Responses to The NNL and small SMR’s

  1. Mark h says:

    You seem to have quite a different concept of the purpose of SMR’s than everyone else. SMR’s are mass produced standardized reactor designs which unlike the entire current generation of individually designed plants would not be subject to separate regulatory or judicial impediments for each installation.

    Regardless of the specific design, Small Modular Reactors…are factory produced in modules that can be shipped in container sized units, rapidly transported by ordinary ship, rail and truck, rapidly installed at a site. They are subject to rigorous safety and and quality control at the factory but insulated from fatuous legal attacks at the installation point…which are the primary cost of traditional nuclear plants.

    • daryan12 says:

      As I discuss in the link below (and something the NNL seems to agree with, up to a point) mass producing any product inevitably involves compromising the design somewhat to achieve a design that can be mass produced. Unfortunately, such a compromise inevitably means a reactor that is less fuel efficient (among other things), looses its economy of scale and comes with all the excess baggage costs associated with any one construction. In essence such an approach is unlikely to be competitive with bulk nuclear power or many alternative (both fossil fuel based or renewable).

      Many of the supposed factors (such as the idea that the government will magically lift all regulation of nuclear power just because the industry say’s its small reactors are safe…and that the public will be okay with that!) in favour of SMR’s are at best unproven, at worse highly dubious.

      While the NNL seems to think there may be some niche market for SMR’s (heat sources and distributed grid power sources), that’s the best that could be expected.

  2. daryan12 says:

    I received the following comment to this page, which oddly enough the author chose to publish on this page instead:

    This reply to daryan12 re-parented here, for readability. For the convience of said staff’s admin I thought I’d post it and my reply here:

    I looked into SMR’s sometime ago and jist of it is that mass production involves striking a compromise between performance and ease of manufacture. This is why you can get a mass produced car like an NSX or a RX-7 for tens of thousands, while a Ferrari the prices start at $250,000. Its why Concorde was a technical success but an economic failure compared to the 737 or 747.

    I looked into what you claimed to have been a look into the issue, and found you contradicted yourself. You implied that only a few 180 MW(e) mPower (let alone 45 MW(e) NuScale or 25 MW(e) Hyperion) units could be sold, limiting the market and increasing the per-unit price to Ferrari levels. On the contrary: if the cost falls with the number of units built, smaller reactors will cost less. Also, the factory-built nature of SMRs reduces the amount and duration of on-site construction and allows a shorter construction schedule. This cuts the cost of financing.

    The mere fact of smaller unit size allows service in many more markets than GW-scale PWRs. Take Hawaii as an example. The average power demand for the entire island chain last August was 1167 MW (868 GWH for the month) which, not being sufficient to sustain a single conventional reactor for any island, was served mostly by oil and coal. A number of mPower reactors could de-carbonize most of the state’s electric supply, and serve as the base for the electrification of its ground transport as well. Given how much gasoline costs in Hawaii and how small the islands are, it should be a natural for BEVs which are a natural complement to nuclear baseload power.

    Wouldn’t it be great if even isolated islands could have completely carbon-free electricity? 24/7, not the noon-peaking, night-absent supply of PV which demands combustion-driven backup?

    Last, the reason a Ferrari costs so much is not because it’s so hard to produce Ferrari performance. It’s because Ferraris are produced and sold in limited quantities and high prices to serve as status symbols. An automotive expert of my close acquaintance once told me of the shoddy workmanship of a Lamborghini, like windshield sealant obviously applied sloppily by hand. If you think SMRs would be serving such a market, you’re too deluded to be taken seriously. For you to accuse ANYONE of being “batshït crazy” is, well… ironic.

    In the real world, a 60-year run of a 1 GW light-water reactor creates enough plutonium to start roughly 1 GW of fast-spectrum reactors, like S-PRISMs. The spent fuel of the LWR will run the fast-spectrum reactor for hundreds of years.

    One can scarcely think of a worse thing to try and mass produce as an S-PRISM (overly complex, exotic materials used, largely unproven design, oh and you’re aware it has a positive void co-efficient?).

    Since you imply expertise on your own part, I ask you to elaborate:
    1. What complexity in the S-PRISM is excessive… and what/who drives that?
    2. What exotic materials are used? Steel and metallic sodium are commodities. The zirconium/niobium alloy used for water-cooled reactor fuel cladding is far more exotic.
    3. Since the EBR II ran for 30 years and the EBR well before it, what part of the design can be considered “unproven”?
    4. Under what conditions can the sodium coolant, which boils at 883°C, be expected to create voids?

    I remind you that the EBR-II was tested under two loss-of-cooling scenarios starting from full power operation. In both tests, it shut down as designed without external intervention and without any harm to the reactor, fuel or systems. S-PRISM is designed to be passively air-cooled in a loss-of-grid shutdown scenario. There are no pumps to lose power or fail, no water supplies to run out. All your catastrophic Fukushima visions… impossible.

    In short the idea that by sacrificing economies of scale you can somehow make an industrial product cheaper is little short of ridiculous.

    On the one hand, the anti-nukes claim that nuclear reactors are too big and too centralized. On the other hand, they argue that making them smaller sacrifices economies of scale. That rat stinks too much for anyone who isn’t deeply into denial to fail to smell it.

    And my reply:

    As I pointed out before (I’m going to avoid repeating the arguments, read the article above or here if you don’t understand) the cheapest way to make nuclear energy is with large LWR cores. There are sound engineering and economic reasons to support this, which would explain why the bulk of the nuclear establishment is pursuing this approach. While both I and the NNL do point to certain unique advantages of SMR’s (greater flexibility, higher safety, etc.), as they involve sacrificing economies of scale, inevitably SMR’s will work out as more expensive per MWh.

    And inevitably if the costs are higher one has to question where the large level of orders needed to allow the cost reductions you hint at (side stepping the entire argument as to whether its technically possible to achieve such cost reductions anyway) will come from.

    There is no “contradiction” here, what we’re saying is that even the cheapest form of nuclear energy is more expensive than a number of the alternatives (see Peter’s article on this), so surprise, surprise an even more expensive again form of nuclear is also going to be more expensive.

    Indeed, If SMR’s were such a brilliant idea then why is it that the only nuclear energy projects under actual construction are all large LWR’s? (we’ll exclude the paper projects you mention that exist only on powerpoint slides). The US, UK, French and Russian navies have been building small reactor cores of the size you describe for +40 years and one has to question if it’s simple as you suggest, why aren’t they mass producing them? One has to assume that, unlike yourself, those running these companies know what they’re doing and understand the difficulties in doing this.

    No ordinary steel alloy (at least the ferritic steels favoured for forgings such as nuclear reactor cores) could survive the temperatures and conditions you describe (that said, I recall the actual propose operating temperature of the S-Prism being somewhat lower that 886’C), certainly not when we factor in the effects of sodium exposure, neutron bombardment, etc. There are alternatives (see article below) ranging from “high-temp” steel alloys, nickel alloys or indeed even concrete (used for a number of German high-temp reactor experiments). But this imposes a variety of constrains on the manufacturing processes applied and how the plant is operated, not just to the core but also the heat exchangers, turbine set, etc. This will inevitably feed into higher costs and lower rates of production.

    Ultimately you’re trying to argue that a reactor capable of undergoing more challenging operating conditions can be built cheaper (i.e. a Ferrari’s cheaper to build than a Ford Focus)….???

    You seem to think LWR’s are a bad idea because they use Niobium as a fuel cladding (I thought you were in favour of LWR’s? now who’s contradicting themselves!). Well so too do Fast reactors! One of my textbooks (Materials by Higgins, chapter 20) specifically highlights the use of Niobium in the Dounreay Fast Reactor.

    Positive void co-efficient? Not a controversial statement, it’s well known that these reactor types possess this. What I find odd is that a supposed advocate of this reactor such as you’re self doesn’t know about it (or is it that you filter out any information that might snap you out of your fantasy?). Its mentioned in several assessments of the S-PRISM, including those by the UK authorities. Here’s a paper that discusses the possibility of mitigating it using a technetium layer.

    EBR II
    As I believe Chris Arcus has pointed out, and as I discuss here, FR’s have a nasty habit of going pear shaped when designs are scaled up (as Dounreay, Super-Phenix and Monju have proven). And it’s often not been the core but the heat exchangers that have proven to be the major stumbling block. Reports by sources such as MIT, UCUSA and IPFM have concluded that Fast Reactors are going to be more expensive than LWR’s or indeed other proposed waste disposal options.

    Unfortunately, like so many FR advocates, you don’t actually understand what it is that you’re advocating…cos if you did then you might understand why so many, even within the nuclear industry, aren’t terribly keen on it!

    Yes how should we power a volcanic Island? Now I recall Peter describing his visit to a similar volcanic Island in the Atlantic recently, indeed I visited the same place myself last year. From where do they get the bulk of their energy I wonder? I’ll give you a clue, it starts with “G”…..

    You’re problem E-Pot is that you can’t see the wood from the trees. It offends your ego that there might be situations where nuclear power isn’t the best alternative and you can’t bring yourself to admitting that.
    This precisely why I went from being pro-nuclear to against it. Its supporters seemed more interested in dreaming up megalomaniac scale fantasies that would never be practical, economic nor politically acceptable, becoming obstacles to progress and generally wasting lots of time and public money.

  3. Thank you for your in depth analysis and well referenced technical reporting and commenting. It is a valuable contribution to our understanding. I read your reports and did further research. I came to similar conclusions. No other kind of reactor worked more successfully than BWR and PWR. Helium cooled reactors appear safer, but never scaled economically. All reactors require exotic technology. I find the obsession with reactors misses the point. Life cycle analysis and the entire mining, waste, enrichment infrastructure require attention. Even a perfect reactor does not overcome those problems. Although conventional reactors do not require reprocessing, breeders or fast reactors do even for waste burn up. Reprocessing is a complete failure, costing billions to clean up, negating any benefit of waste burn up. In some sense, the industry appears to be a hoax, set up by the military industrial complex to reduce the costs of making bombs. We are left with the aftermath. A ruse of energy generation, which when the millennia of waste storage and disaster costs are factored contribute little or nothing to humanity. Like you, I believe gas reactors were much closer to an acceptable form, if all the other negatives were dealt with. Unfortunately, they are not. Few of the negatives are actually borne by the industry. TMI utility was bankrupted by the disaster. Defunct mining companies left toxic pit mines all over North America. The taxpayer is footing the bill, just like they are doing at Vogtle, San Onofre, Olkiluoto and more. Nuke cheerleaders occupy a rarified atmosphere of fantasy unobstructed by the gritty reality of nuclear failures.

    • daryan12 says:

      I suspect the British nuclear supporters would point to their AGR (advanced gas cooled reactors), which still constitutes the bulk of the UK’s nuclear capacity, as an example of a gas cooled plant that did successfully scale up.

      Of course the AGR’s ran substantially over budget, which meant nobody else in the world built them. And they are proving to be very expensive and difficult to decommission, ditto the MAGNOX plants that came before them (mostly down to those graphite cores and fuel assemblies). And France and Germany are having horrendous problems with some of the their relatively small gas cooled reactors that they’ve been decommissioning (including the pebble bed prototype). So I suppose it depends how we define the word “success”.

      As for the LCA’s. I tend to avoid getting caught up in this debate too much. Certainly, when one considers the full LCA of nuclear (i.e. mining, processing and decommissioning, not just the construction and operation phases) its quite probable that the LCA’s of mature renewable sources, such as wind power, is much lower. Its harder to call as regards PV, in large part because of long term LCA related unknowns i.e. are these panels going to be dumped or recycled at the end of their life? will future trends towards thin-film continue, etc. Some of the worse case scenario’s (Varun etal 2009) for PV are higher than the full LCA values for nuclear from Sovacool or Bilek. However, either way, the point I make is even if we take the worse case scenario’s here for either nuclear or PV, that’s still an order of magnitude lower than any option involving fossil fuels.

      Mine tailings
      And yes a large chunk of the problem with nuclear is the politics. Not only have we the situation where the companies building or running the plants don’t take on responsibility for the waste, both from the spent fuel and mining operations, but neither do governments always take these on either.

      Much of the French Uranium supplies comes from Niger and there are questions as to who is going to clean up the mess, particularly as one of their mines flooded a few years ago and last I heard they still hadn’t pumped it out or started any sort of decontamination/site clean up. Now if this pile of waste was sitting in some French voters back garden, would they be as keen on nuclear power?

  4. Pingback: Beware of the Elephants | daryanenergyblog

  5. Pingback: Hinkley C update – Chaos and TINA | daryanenergyblog

  6. Pingback: A closer estimate on nuclear energy cost options | daryanblog

  7. Pingback: Nuclear Requiem | daryanenergyblog

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.