Small Modular Reactors

They may finally be on their way. But as the article says, we won’t understand their economics until they’re actually put into operation. And as usual, the Union of Confused “Scientists” will try to throw up roadblocks.

Interestingly we were working with Flour Daniel when I was at Rockwell working the Space Exploration Initiative on ISRU. I wonder how applicable these would be on the moon or Mars? There’s water for cooling in both places.

47 thoughts on “Small Modular Reactors”

  1. The idea is certainly interesting and I am a big proponent of nuclear. But I think this comes a decade too late. At least for North America. With cheap natural gas it will be much cheaper to use a high efficiency gas turbine or fuel cell than these nuclear generators. Perhaps for isolated places like Hawaii something like this would make sense. But not in the CONUS.
    Here in Europe I think it would make more sense since it would reduce dependency on Russian and Middle East natural gas but there’s way too many NIMBYs for it to work in practice.

    1. And also the continuing decline in the cost of power from wind and solar. The latter is falling by 10%/year. Storage is also getting cheaper. Assuming these trends continue the window for SMRs could be narrow, if it hasn’t closed already.

      1. You also need to factor in the cost of a transcontinental distributed power grid (preferably hardened). Solar from a good chunk of the country in the winter is going to be essentially 0.

        1. When and if solar becomes the cheapest source of energy, you will see energy-intensive industries move to places where it is reliably available. Yes, high latitude locations will have problems in winter. This means heavy industries will tend to abandon such places. Sad news for Europe and western industrial civilization; good news for the equatorial countries.

          1. When and if solar becomes the cheapest source of energy, you will see demand take off, and bottlenecks appear, and the cost will mushroom.

            It is a bad idea to extrapolate cost of a niche product to cost of a product in high demand. It doesn’t scale linearly.

            In the end, absent a huge leap in efficiency, solar will always be a niche product. The amount of material required for even a modest dent in our appetite is just staggering.

          2. Bart: not sure why you think huge leaps in efficiency are necessary for solar to take over. Most of the reduction in the cost of solar-generated electricity has been due to large reductions in cost of modules, not the (fairly modest) increase in their efficiency.

            The only bottleneck I can think of for solar is availability of silver for contacts, but that is already being phased out due to cost. Contacts using electrodeposited copper/nickel will likely take over. Other than that, silicon PV is made only with materials available in essentially unlimited amounts. Land is also not a significant constraint.

  2. The article spends way too much time on financing and not enough time on the real issue, which is the hostile regulatory environment for licensing new designs. Financing will cease to be an issue, if an investor or group of investors can rest assured that the NRC is not going to reflexively sh!tcan any particular approach just because it’s not the way the NRC has always done it.

    1. Well I have a different opinion about that. The NRC has not been the main issue in my opinion. Just look at it. They’ve licensed the AP1000 just fine and AFAIK they made a fast track procedure for NuScale to get licensed since it’s a different concept from the usual. So I think they have been quite responsive. I would say the problem is not at the federal level. Both past administrations (Obama and Bush) tried to push new nuclear construction forward.
      The main issue IMHO is local governments and populations (NIMBY). And the high capital costs involved in construction of large nuclear reactors, which this design seeks to address.

      1. Another example of this NIMBYism is “ultra-supercritical” coal power, basically burning coal at temperatures high enough that it has to be cooled with “supercritical” steam well above the critical temperature and pressure (which is roughly 700 F and over 200 atmospheres of pressure for water).

        The US has built one such plant, the John W. Turk Jr. Coal Plant which was embroiled in numerous, massive lawsuits for five years.

        Though first proposed in 2006, lawsuits aiming to protect the ecology surrounding the project’s proposed site delayed its groundbreaking. Plaintiffs cited potential damage to the area’s fish, wildlife, grasslands, and cypress and hardwood groves.

        As part of a settlement reached in December 2011 with the Sierra Club, the National Audubon Society, Audubon Arkansas and the Hempstead County Hunting Club, American Electric Power/SWEPCO agreed to close one of the 528-megawatt generating units at its J. Robert Welsh Power Plant in Texas by the end of 2016 and purchase 400 megawatts of renewable energy capacity by the end of 2014.

        The settlement also required the company to contribute $8 million to The Nature Conservancy, $2 million to the Arkansas Community Foundation and reimburse $2 million in legal fees.[6] American Electric Power/SWEPCO agreed to never install additional generating units at the plant or build another coal-fired facility within 30 miles.

        And this is in Arkansas. Imagine what would have happened if they had tried in California.

        In comparison, China is thought to be building vast numbers of this new type of plant right now. The Center for American Progress (CfAP) report brags on how efficient Chinese plants are while completely glossing over the NIMBY issues that help make US coal power so uneconomic.

        To be sure, China still has plenty of older coal-fired power units that are not using the most advanced technology. According to the latest third-party research from S&P Global Platts, which provides research on global energy infrastructure, when the data set is expanded to include all operating coal-fired power capacity in China—which totals 920 gigawatts—approximately 19 percent uses ultra-supercritical technology, 25 percent uses supercritical technology, and 56 percent uses subcritical technology.11 However, the new builds are increasingly ultra-supercritical plants, and Beijing is steadily ratcheting up the emissions requirements and efficiency standards for those older plants as well.

        By 2020, every existing coal-fired power unit in China must meet an efficiency standard of 310 gce per kilowatt-hour; any units that do not meet that standard by 2020 will be retired. In contrast, none of the current top 100 most efficient U.S. coal-fired power units would meet that same efficiency standard today. (see Table A2)

        The CfAP goes on to claim that because the US currently has cheaper options, it doesn’t make sense for coal power to continue. That breezy assurance may well be true, but the future is notorious for being hard to predict.

  3. “With cheap natural gas it will be much cheaper to use a high efficiency gas turbine or fuel cell than these nuclear generators. ”

    In many places that will be true.

    In some places, perhaps as many as where it is true, the cost of fuel resupply will make it untrue. Consider outposts around the Arctic or Antarctic circles – for which either a half-year’s supply of LNG must be shipped in and stockpiled for winter; or for which a more-or-less steady stream of new fuel must be lifted in despite all adverse weather conditions.

    Consider any remote location far from pipelines, for that matter. Pacific Islands, the interior of less-developed continents, or the central urban areas where traffic interferes with fuel delivery by vehicle or the construction of infrastructure to build out a fuel pipe.

    Nobody knows, yet. This is the “I, Pencil” problem. There are a lot of variables and nobody can — or should — pronounce a priori that THIS solution compares to THAT solution in ONLY ONE fashion.

    Let entrepreneurs, engineers, bankers and consumers duke the question out in the markets, and we’ll see which is really a better and cheaper use of resources.

    1. In those cases typically the answer has been petroleum (either small diesel generators or fuel oil power plants). It’s high density, it can be stockpiled, it can be used for other purposes like heating, etc. Take the example I mentioned before, Hawaii, it generates a large fraction of electric power from petroleum. The islands are too small for hydro to be a big contributor and geothermal power plants can’t be used on many of the islands either. I think nuclear would make sense here, there’s even a military base there, still there’s no nuclear power plant in Hawaii. The Arctic, like you mentioned, is another definitive possibility and in fact there are Russian designs for such a thing (Akademik Lomonosov). The question is if there is enough demand to make such an industry economically viable.

  4. The debate around the death penalty used to revolve around cost. But then people who were against the death penalty realized the way to remove that argument is just to make the death penalty more expensive to carry out through the use of lawfare.

    Nuclear is much the same. It will always have some higher costs relative to other sources of energy due to lawfare. I predict that this will happen to wind and solar about the time they actually catch on in any significance. Right about that time, environmentalists will “discover” how bad they are for the environment and the lawfare will commence in earnest.

    In the end, no source of energy comes without impact but the greatest sin is that abundant energy enables humans to thrive. So, whenever solar and wind cross that threshold, it will become an evil technology regardless of their production costs. Should those production costs actually be cheaper? Well, there are always ways to increase them.

    1. To a large degree the construction costs in a nuclear power plant are the large concrete containment dome and steel pressure vessel. These typically take several years to build and require large amounts of material and manpower. There have been several proposed designs which claim to be leak proof or to have safety features which render these not necessary but none of these have been proven in practice. At one point the Germans invested in pebble bed reactors for example which were claimed to be incapable of a meltdown or fire hazard due to the way the fuel was stored encased in graphite balls. It turned out the manufacturing process of the graphite balls was susceptible to cracks and the balls got stuck in the mechanism. Also later when Chernobyl happened people figured out that graphite could flame out a lot more easily than was expected.

      Figure out a way to dispense with the expensive containment structure and the costs would go down.

    2. Solar and wind power are terrible for the environment. Wind power shreds birds, and requires strip mining of rare Earths. Solar requires toxic chemicals which have already rendered whole cities in China uninhabitable. And, they require so much of these things to produce a pittance of power that, for any significant penetration, the impacts would be truly horrific.

      1. Calling bullshit on you claim about solar there. Which toxic chemicals are you talking about, and why does it have to be released into the environment.

        1. And, mind you, this is in the current state, wherein solar energy supplies only a tiny fraction of worldwide energy demand. Scaling it up to make even a small yet significant dent will magnify the problems many-fold.

        2. Reading your links there, it is as I thought. Most didn’t even mention specific materials, just generalities about “toxic waste”. There is no need for PV manufacture to release toxic materials into the environment. Things mentioned like sodium hydroxide and hydrofluoric acid can be neutralized to completely innocuous materials. Toxic heavy metals like cadmium are not used in silicon PV, the technology that has won 90+% of the market.

          For your information, the most environmentally impactful part of silicon PV manufacture is the making the glass and metal supports for the cells and modules.

          The “300 times more waste than nuclear” article was rather reprehensible. Yes, let’s compare mildly annoying non-radioactive waste vs. highly radioactive spent fuel, on a pound-by-pound basis.

  5. Figure out a way to dispense with the expensive containment structure and the costs would go down.

    High temp gas PBRs address that. China’s HR-10 intentionally had all power turned off to it in one test. It self moderated and cooled down.

    Regardless of design, I think the module sizes NuScale are using are still too big. One of of the faults of our present power generation and distribution system is a lack of decentralized generation and independent smaller grids that could avoid cascading failures.

    The side benefit to even smaller modules (semi-trailer sized units or smaller) would be adaptability to space use, or rapid shipping of generating capacity to where it is needed.

  6. I wonder how applicable these would be on the moon or Mars? There’s water for cooling in both places.

    Cooling a powerplant with water ultimately means allowing water to evaporate to carry away the waste heat. This is inherently an open cycle process. Dissipating 10 MW of waste heat would involve evaporating perhaps 3 kg of water per second, or 260 tons of water per day. This doesn’t seem terribly practical for the moon or Mars.

    A moon or Mars reactor probably wants to operate at higher temperature to make waste heat disposal easier, either by radiation or conduction to the very thin Martian atmosphere.

  7. While nuclear capacity has gone up…

    The last two power plants to be built in the US were the Watts Bar plant, which began construction in 1973, was completed in 1990, and didn’t begin commercial operation until 1996, and the River Bend plant, which was built in 1977 and went online in 1986.

    So how has capacity gone while the last new plant was in 1977?

    Because existing plants have been upgraded which is harder for activists than stopping new plants. The activists aren’t going to let any size of new plant be built.

  8. “I wonder how applicable these would be on the moon or Mars? There’s water for cooling in both places.”

    LRO’s LEND data doesn’t support Spudis’ optimistic prediction of two meter (or more) thick glaciers.

    Initially the LCROSS ejecta was thought to be 5.5% water. But a year later the team said they over-estimated volatile content by a factor of 5.5. So 1% water in the LCROSS ejecta.

    There might be some water in the lunar cold traps. But it would take a lot of water to cooling nuclear power plants.

    1. Using water cooling is a known but inferior tech. We could be building low pressure thorium reactors that are both cheaper and safer with no meltdown possible that aren’t tied to a water source.

  9. No need to evaporate the water on the Moon or Mars for cooling. Just melt it which you need to do anyway to get at it for other uses.
    Solar should work fine in high Earth orbit where there are no clouds and it is never night. On Earth the scale of storage required makes it hopeless. How do you cope with not just overnight but days of cloudy weather in a row? Reliable power? I know, build some nukes for backup, then you won’t need the solar anyway.
    IFAIK the liquid flouride salt reactors don’t need containment, just shielding

    1. So, where does the heat end up going? If the water isn’t being evaporated in an open cycle the heat must be either radiated or transfered to another fluid. Both of these are difficult and benefit from occurring at a higher temperature than a water cooled system would support well.

      1. If nuclear is being used in space, the heat is being radiated. Conveniently, in space shadows are very cold. The ISS uses ammonia pumped through pipes and keeps its radiators in the shade. Once it gets through the radiators the ammonia is pumped back into the heat exchanger on a closed cycle. A nuclear reactor would either use that or some other fluid (Helium?) to keep the heat moving from heat exchangers to radiators.

        1. Right. And the size of your radiator goes as temperature^-4. So you really want to operate your radiator at as high a temperature as you can, probably higher than the temperature for which water would be a desirable working fluid. Terrestrial LWRs exhaust their waste heat at a temperature that would be way too low.

          1. Where is your crew?

            On the third planet.

            There is no third planet . . .

            Don’t you think I know that? There was, but not anymore!

    1. Why not? Are the electrons from wind turbines and PV arrays somehow less manly than those from nuclear powerplants?

      1. Wind and solar simply don’t scale. Steven Den Beste (died 2016) did the math decades ago.

        1. Um, that’s bullshit. Gound based solar scales well beyond the entire primary energy consumption of our current global civilization.

          1. I’m not going to redo Steven’s math, but…

            Solar radiation on earth is about 20% of 1367 watts per square meter.

            Thorium reactor specific energy is 79,420,000 MJ/kg.

            No comparison.

            As of the end of 2016, the U.S. had 40 gigawatts (GW) of installed photovoltaic capacity.

            Just one nuclear reactor in AZ (Palo Verde) produces almost 4 GW.

            Try to cover the Palo Verde site with solar panels and see what you get.

          2. Palo Verde site is 1600 ha or 16,000,000 sq meter
            times 70 watts is about one GW.

            So not too bad, but that’s using every square inch for solar panels vs buildings and parking lots and lot’s of unproductive space for a nuclear plant.

          3. Solar radiation on earth is about 20% of 1367 watts per square meter.

            Thorium reactor specific energy is 79,420,000 MJ/kg.

            No comparison.

            Of course there is no comparison, because they aren’t even in the same dimensions of physical units. They literally cannot be compared.

            In no way do the numbers you have given show that solar cannot be scaled to very high power output. You aren’t making a coherent argument. Yes, solar will require more land area than nuclear reactors. No, this isn’t really a problem, since we have enormous amounts of land, and land is very cheap.

          4. they aren’t even in the same dimensions of physical units.

            Sorry about that, it was just a few quick googles, but still indicative.

            Having lots of cheap land doesn’t change the economic rule of Sowell, “everything is scarce and has alternate uses.”

            We aren’t going to pave the planet with solar cells, although I would agree there is plenty of room for growth. I’ll see if I can find SDB’s article which is pretty thorough and definitive.

          5. SDB also said this…

            The biggest drawback of wind/solar is that they generate power when conditions permit them to do so, not when demand requires them to do so. And there’s no practical way to store electric energy in adequate quantities to deal with this without unacceptable losses or unreasonable capital and/or operating expense.

            So it’s not just that it doesn’t scale. It’s understanding the full magnitude of the problem,

    1. Yes, I thought that was so obvious I didn’t need to mention it, but then provided the SDB quote which addresses the point even better.

      1. And when it comes time to go fully renewable, energy storage will be used to smooth over the intermittent nature of the sources. Energy storage costs are falling even faster than PV costs have been falling. Say thank you again to Mr. Musk.

        Oh, and nuclear seems to be falling off a cliff now in the US. The V.C. Summer new reactors were just cancelled with 5000 workers fired. The two new reactors at Vogtle are still a go, but the cost estimate for them has now been raised to $25+B. Unless the SMR Hail Mary play succeeds (which I seriously doubt it will), nuclear is dead technology walking in the US.

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