4 ms·

I'm so glad that you brought up TRIGA. For those who don't know, the story of TRIGA is quite fascinating from our perspective. The pitch was rather simple, "Bui

I'm so glad that you brought up TRIGA. For those who don't know, the story of TRIGA is quite fascinating from our perspective. The pitch was rather simple, "Build a reactor that a teenager could play with" (without supervision). And they succeeded. The reactor was designed in the span of a few months. They started in the summer of 01956. The first one was commissioned and built in May of 01958. And it ran until 1997, steadily producing 250 MW with occasional "pulses" up to 1,000 MW, the entire time. Let's take a minute to appreciate that. They went from design to implementation in less than 2 years, that's lightning fast even in startup terms. And their design has never malfunctioned, ever. AFAICT, there are 66 of these reactors out there in the world that have operated for nearly 7 decades with 0 incidents. Some of them are even true to form and are operated by teenagers! And I suspect that's the real reason why nuclear power is so expensive. While regulatory burdens, subsidies, and general corruption do indeed explain the exponential cost increases for nuclear power, the truth is that these are proximate causes. The distal cause is simple; the reactors suck. We've been designing them wrong for decades now, and we need to make rethink them from the ground up. Luckily, I'm not the only person who thinks that. Far more smarter people have been bringing the fun back to nuclear engineering, and we are finally getting a series look at concepts like pebble bed reactors. I hope that someday we'll have forever batteries and power sources that are small, self-contained, and can be carted for use anywhere, including space. Achieving this goal requires everything from the kinds of modular designs NuScale https://www.nuscalepower.com/ https://www.nuscalepower.com/ and Terrapower https://www.terrapower.com/ https://www.terrapower.com/ are working on to Zeno Power's radioisotope systems, https://www.zenopower.com/ https://www.zenopower.com/ I am excited for the future again.

kragen 4y ago
It could happen! But, right now, at most latitudes, building a PV farm is cheaper than building a coal power plant with the same average output, and a coal power plant is basically a conventional nuclear power plant without the reactor. I think that, to be cost-competitive with PV as a source of energy, nuclear reactors need either much cheaper heat engines than a Parsons turbine, or some way of converting nuclear power to useful forms that doesn't start with using it to heat something up. The only group I know of trying to do this is https://hb11.energy/ https://hb11.energy/, whose plan is to laser-initiate an avalanche of boron-11/hydrogen "fusion" and throw the resulting alpha particles up a million-volt potential difference. Though it's not guaranteed, that might end up being cheaper than a steam turbine and generator. Without such improvements, nuclear energy is only really appealing in environments where PV and wind aren't an option — like submarines, aircraft carriers, Antarctic research stations, deep-space probes, and Scotland — or as a hedge against unforeseen difficulties in scaling up grid-scale energy storage and the like. But I might be wrong about where the costs in coal plants come from, and I'd be very grateful to find that out. I really appreciated your "On Apple’s “Expanded Protections for Children”," by the way.
- adrianN 4y ago
  To be fair, to make the average output of a PV plant comparable to the average output of a nuclear plant you need to add some storage, which drives up the cost a bit. Probably not enough to account for the extra cost of nuclear though.
  - kragen 4y ago
    You do, although it's still unclear how much storage you'll need to add. On the other hand, while you can't turn PV plants on at night, you can't turn conventional nuclear plants off, and so to go all nuclear you need some form of load following: either gas peakers, or PV that carries a higher load during the day, or storage, or giant resistor banks. Evidently naval reactors are a lot better at this, though.
    - adrianN 4y ago
      As far as I know it's not terribly difficult to model how much storage you'll need. It has a couple of variables, like how well connected your grid is, or how well you can shape demand, but then it's just looking at past weather data and deciding how low you want the probability for blackouts to be. Here for example is a toy implementation: https://model.energy/ https://model.energy/ From what I've heard the amount of storage is not very large if you assume sufficiently large grids and the total system cost is expected to be lower than what we currently pay for electricity.
      - kragen 4y ago
        Demand response is the biggest unpredictable factor, I think, but demand is also unpredictable. Power plants are commonly depreciated over 30 or even 40 years. Electricity consumption in the US doubled during the 01960s, and it doubled in PRC during the 02010s. If the transport sector in the US went all-electric, that would double electrical consumption again even without increasing energy use. How can you predict what fraction of your users will be using electric vehicles 15 years from now, and whether they'll charge them in the daytime or at night? That depends on, among other things, whether they'll go back to working in offices, whether the offices will have chargers, and how much cheaper it will be for them to charge during the day than at night. And that, in turn, depends on what kind of time-of-use rate schedules you can get the public utility commission to approve. Will people insulate their houses more so they don't need to heat them at night? That depends not only on the rate schedule but their future expectations of the rate schedule, as well as what their house buyers' expectations of the rate schedule. How much will superinsulating your walls raise the house's sale price? How about home TCES — if daytime electricity is sufficiently cheap, such forms of energy storage might become popular as a cheaper alternative to superinsulation, and maybe suppress the demand for nighttime electricity further in cold areas; but we don't have any mass-market experience with them right now. Will building codes, or insurance underwriters, impede the wide adoption of TCES after the first homeowner files a massive insurance claim to replace their hardwood floor ruined by a calcium-chloride spill? Will dirt-cheap rail-shipped carnallite drop the price of TCES further than calcium chloride possibly could? Will new carnallite deposits be found, closer to large cities? How about the future of industry? Mass PV rollout will drop the price of energy dramatically, so industrial processes that are currently unprofitable because they use too much energy will become profitable. They might outcompete more energy-efficient incumbents. The first example of this might be aluminum replacing steel in more and more uses; today it's so much more expensive than steel that it's only used in places where its lighter weight is a big advantage, but with lower energy costs (and shorter shipping distances) it might replace steel for many more purposes. Minimills recycling existing steel might be able to fulfill the entire steel demand for quite a while — steel mills that smelt iron from ore would shut down entirely, and the 30-year-depreciated power plants built to supply those mills might find themselves without the demand they were built for. And this might happen by 02039. This is maybe the most predictable outcome of much lower prices for electrical energy, but probably won't be the most dramatic one. So shifts in electrical demand will depend on cultural change, diffusion of innovations, regulatory capture, consumer expectations, and cost-driven substitution in the radically changed economic landscape. The last time the price of energy dropped so dramatically might have been Watt's steam-engine in 01776. The dislocations in society that resulted would have been very hard to predict.
cycomanic 4y ago
Well you leave out the small inconvenient truth that TRIGA is not power generating. The earlier series of the blog post we are discussing actually talks about that a significant fraction of the cost of a nuclear plant is the thermal power plant part, which is the same as for a coal plant for example. Moreover, actually having to use a reactor for power generation significantly increases the complexity of the design, you suddenly need to heat water, which means two different water cycles which mustn't contaminate each other... And having water involved makes things more tricky anyway because of corrosion...
imtringued 4y ago
>The distal cause is simple; the reactors suck. We've been designing them wrong for decades now, and we need to make rethink them from the ground up. Obviously, the vast majority of nuclear power plants are of the suck type. If you want a regulatory blank slate you are going to have to shut them all down and replace them with good power plants. The regulations are there to deal with the "suck" of the nuclear industry. Get rid of the suck and you will make the nuclear industry very unhappy, in other words the legacy nuclear power industry is exactly the problem that drives regulations and costs up.

kragen 4y ago

It could happen! But, right now, at most latitudes, building a PV farm is cheaper than building a coal power plant with the same average output, and a coal power plant is basically a conventional nuclear power plant without the reactor. I think that, to be cost-competitive with PV as a source of energy, nuclear reactors need either much cheaper heat engines than a Parsons turbine, or some way of converting nuclear power to useful forms that doesn't start with using it to heat something up. The only group I know of trying to do this is https://hb11.energy/ https://hb11.energy/, whose plan is to laser-initiate an avalanche of boron-11/hydrogen "fusion" and throw the resulting alpha particles up a million-volt potential difference. Though it's not guaranteed, that might end up being cheaper than a steam turbine and generator. Without such improvements, nuclear energy is only really appealing in environments where PV and wind aren't an option — like submarines, aircraft carriers, Antarctic research stations, deep-space probes, and Scotland — or as a hedge against unforeseen difficulties in scaling up grid-scale energy storage and the like. But I might be wrong about where the costs in coal plants come from, and I'd be very grateful to find that out. I really appreciated your "On Apple’s “Expanded Protections for Children”," by the way.

adrianN 4y ago
To be fair, to make the average output of a PV plant comparable to the average output of a nuclear plant you need to add some storage, which drives up the cost a bit. Probably not enough to account for the extra cost of nuclear though.
- kragen 4y ago
  You do, although it's still unclear how much storage you'll need to add. On the other hand, while you can't turn PV plants on at night, you can't turn conventional nuclear plants off, and so to go all nuclear you need some form of load following: either gas peakers, or PV that carries a higher load during the day, or storage, or giant resistor banks. Evidently naval reactors are a lot better at this, though.
  - adrianN 4y ago
    As far as I know it's not terribly difficult to model how much storage you'll need. It has a couple of variables, like how well connected your grid is, or how well you can shape demand, but then it's just looking at past weather data and deciding how low you want the probability for blackouts to be. Here for example is a toy implementation: https://model.energy/ https://model.energy/ From what I've heard the amount of storage is not very large if you assume sufficiently large grids and the total system cost is expected to be lower than what we currently pay for electricity.
    - kragen 4y ago
      Demand response is the biggest unpredictable factor, I think, but demand is also unpredictable. Power plants are commonly depreciated over 30 or even 40 years. Electricity consumption in the US doubled during the 01960s, and it doubled in PRC during the 02010s. If the transport sector in the US went all-electric, that would double electrical consumption again even without increasing energy use. How can you predict what fraction of your users will be using electric vehicles 15 years from now, and whether they'll charge them in the daytime or at night? That depends on, among other things, whether they'll go back to working in offices, whether the offices will have chargers, and how much cheaper it will be for them to charge during the day than at night. And that, in turn, depends on what kind of time-of-use rate schedules you can get the public utility commission to approve. Will people insulate their houses more so they don't need to heat them at night? That depends not only on the rate schedule but their future expectations of the rate schedule, as well as what their house buyers' expectations of the rate schedule. How much will superinsulating your walls raise the house's sale price? How about home TCES — if daytime electricity is sufficiently cheap, such forms of energy storage might become popular as a cheaper alternative to superinsulation, and maybe suppress the demand for nighttime electricity further in cold areas; but we don't have any mass-market experience with them right now. Will building codes, or insurance underwriters, impede the wide adoption of TCES after the first homeowner files a massive insurance claim to replace their hardwood floor ruined by a calcium-chloride spill? Will dirt-cheap rail-shipped carnallite drop the price of TCES further than calcium chloride possibly could? Will new carnallite deposits be found, closer to large cities? How about the future of industry? Mass PV rollout will drop the price of energy dramatically, so industrial processes that are currently unprofitable because they use too much energy will become profitable. They might outcompete more energy-efficient incumbents. The first example of this might be aluminum replacing steel in more and more uses; today it's so much more expensive than steel that it's only used in places where its lighter weight is a big advantage, but with lower energy costs (and shorter shipping distances) it might replace steel for many more purposes. Minimills recycling existing steel might be able to fulfill the entire steel demand for quite a while — steel mills that smelt iron from ore would shut down entirely, and the 30-year-depreciated power plants built to supply those mills might find themselves without the demand they were built for. And this might happen by 02039. This is maybe the most predictable outcome of much lower prices for electrical energy, but probably won't be the most dramatic one. So shifts in electrical demand will depend on cultural change, diffusion of innovations, regulatory capture, consumer expectations, and cost-driven substitution in the radically changed economic landscape. The last time the price of energy dropped so dramatically might have been Watt's steam-engine in 01776. The dislocations in society that resulted would have been very hard to predict.

cycomanic 4y ago

Well you leave out the small inconvenient truth that TRIGA is not power generating. The earlier series of the blog post we are discussing actually talks about that a significant fraction of the cost of a nuclear plant is the thermal power plant part, which is the same as for a coal plant for example. Moreover, actually having to use a reactor for power generation significantly increases the complexity of the design, you suddenly need to heat water, which means two different water cycles which mustn't contaminate each other... And having water involved makes things more tricky anyway because of corrosion...

imtringued 4y ago

>The distal cause is simple; the reactors suck. We've been designing them wrong for decades now, and we need to make rethink them from the ground up. Obviously, the vast majority of nuclear power plants are of the suck type. If you want a regulatory blank slate you are going to have to shut them all down and replace them with good power plants. The regulations are there to deal with the "suck" of the nuclear industry. Get rid of the suck and you will make the nuclear industry very unhappy, in other words the legacy nuclear power industry is exactly the problem that drives regulations and costs up.