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You could make an argument that Fission has succeeded on a technical front (large amounts of electricity are being generated for multiple countries at this prec

You could make an argument that Fission has succeeded on a technical front (large amounts of electricity are being generated for multiple countries at this precise moment), and that most of its problems are social.

pfdietz 6y ago
No, the primary problem of fission is economic, not social. That's why it's been a global failure. It simply has not been able to compete with the alternatives. And this is why fusion is such a boondoggle. It's similar to fission, only even more complex and expensive. It's like the opposite of Keep It Simple, Stupid.
- cromwellian 6y ago
  No, Pressured Water Reactors (LPWRs) are large, expensive, dangerous, etc. Molten Salt Reactors, especially Thorium Molten Salt Reactors (e.g. LFTR) are much much smaller and passively safe. What you're missing is that cost scales with volume. If you use a technology that allows you to reduce your reactor size by a linear factor of 2, you reduce its reduce volume and cost by a factor of 8. Likewise, while ITER is uber expensive like large PWRs, ARC is 10 times smaller, and a factor of 30 times or more cheaper. It's also not as complex as some fission reactors, the most complex elements being the HTS magnets and the blanket. This is the problem with ITER and PWRs, they have convinced the public that nuclear energy is inherently dangerous and expensive and impossible to make substantially safer, cleaner, and cheaper, but that is false. You should look up at the history of LPWRs vs MSRs from the guy who invented them. There's a documentary on the Oak Ridge Molten Salt Reactor experiment. He himself thought LPWRs were too dangerous requiring ginormous size and shielding, but the US government and cronies, preferred LPWRs, and so MSRs were abandoned, despite successful trials.
  - pfdietz 6y ago
    The Molten Salt Reactor designs I have seen have lower volumetric power density than PWRs. The MSRE reactor had a volumetric power density of 2 MW/m^3, a factor of 10 lower than a commercial PWR (counting the volume of the entire primary reactor vessel; the power density in the core of a PWR is a factor of 5 higher than that.) Of course that was an experiment, but look at something like Moltex's design and the power density is still lower than a PWR, last I looked. > Likewise, while ITER is uber expensive like large PWRs, ARC is 10 times smaller, and a factor of 30 times or more cheaper. The ARC design is smaller than ITER, but it's still very much lower (a factor of 40) in power density than a fission reactor.
    - cromwellian 6y ago
      The power density isn't the only variable that matters. The difference doesn't matter if the cost to build a Thorium Molten Salt Reactor is much lower, especially in terms of safety and size. MSR's don't need enormous containment vessels, they also reprocess fuel. Here's some links showing power densities inline with PWRs, or greater: https://www.nextbigfuture.com/2013/12/molten-salt-reactor-about-50-times.html https://www.nextbigfuture.com/2013/12/molten-salt-reactor-ab... "Extrapolating from other liquid-to-liquid heat exchangers, roughly 150 MW/m3 is a practical upper limit to the power density of a primary-to-intermediate salt heat exchanger. For comparison, pressurized-water reactor core power density is ~110 MW/m3." https://info.ornl.gov/sites/publications/files/Pub29596.pdf https://info.ornl.gov/sites/publications/files/Pub29596.pdf
- ncmncm 6y ago
  The fact is, there is no reasonable expectation of ever getting viable commercial power from a tokamak-style fusion reactor. The density of energy production, in watts per cubic meter, is so low that an impractically large volume of confined plasma would be needed, requiring a reactor many times larger than a fission plant for the same power output. But fission-driven power is itself too expensive to produce to justify deploying on its own merits. Furthermore, since the power must be extracted by intercepting high-energy neutrons after they have blasted through the plasma focusing apparatus, such a plant would destroy its most expensive parts in a short time, requiring frequent rebuilding -- by robots, because of induced radioactivity at the work site. There has never been any expectation of practical commercial power resulting from plasma-confinement thermal-neutron fusion projects. Their only plausible budgetary justification is as a jobs program for high-neutron-flux physicists. They are called for by military policy as a population to draw personnel from for weapons work. Coal has always been cheaper than fission. Solar and wind power costs are much less, and continue falling; and numerous viable energy storage methods, all demanding no fundamental research -- gravity (solid and aqueous), underground and underwater compressed air, LH2, ammonia, methane from captured CO2, even powdered iron -- vie only for which will end up cheapest to deploy and operate. If a commercial reactor were ever built and made to work, it would take many decades just to break even on the money already spent to date, before bevinning to pay down its own construction -- even presuming it could find a market for its output. In practice, without continued public subsidy as long as it operated, its debt would continue to grow indefinitely. The only responsible course for the future is to cancel all publicly funded thermal-neutron fusion work, immediately.
  - pfdietz 6y ago
    I think there is a slim chance that nuclear could remain relevant. The key would be greatly reducing the cost of the non-nuclear side of the power plant. Perhaps the best approach would be replacing large steam turbines with far more compact supercritical CO2 turbines. This would require temperatures somewhat higher than from PWRs. And this (not thorium, not waste destruction, nor really even safety) is perhaps the best argument for molten salt reactors.
    - 6y ago

pfdietz 6y ago

No, the primary problem of fission is economic, not social. That's why it's been a global failure. It simply has not been able to compete with the alternatives. And this is why fusion is such a boondoggle. It's similar to fission, only even more complex and expensive. It's like the opposite of Keep It Simple, Stupid.

cromwellian 6y ago
No, Pressured Water Reactors (LPWRs) are large, expensive, dangerous, etc. Molten Salt Reactors, especially Thorium Molten Salt Reactors (e.g. LFTR) are much much smaller and passively safe. What you're missing is that cost scales with volume. If you use a technology that allows you to reduce your reactor size by a linear factor of 2, you reduce its reduce volume and cost by a factor of 8. Likewise, while ITER is uber expensive like large PWRs, ARC is 10 times smaller, and a factor of 30 times or more cheaper. It's also not as complex as some fission reactors, the most complex elements being the HTS magnets and the blanket. This is the problem with ITER and PWRs, they have convinced the public that nuclear energy is inherently dangerous and expensive and impossible to make substantially safer, cleaner, and cheaper, but that is false. You should look up at the history of LPWRs vs MSRs from the guy who invented them. There's a documentary on the Oak Ridge Molten Salt Reactor experiment. He himself thought LPWRs were too dangerous requiring ginormous size and shielding, but the US government and cronies, preferred LPWRs, and so MSRs were abandoned, despite successful trials.
- pfdietz 6y ago
  The Molten Salt Reactor designs I have seen have lower volumetric power density than PWRs. The MSRE reactor had a volumetric power density of 2 MW/m^3, a factor of 10 lower than a commercial PWR (counting the volume of the entire primary reactor vessel; the power density in the core of a PWR is a factor of 5 higher than that.) Of course that was an experiment, but look at something like Moltex's design and the power density is still lower than a PWR, last I looked. > Likewise, while ITER is uber expensive like large PWRs, ARC is 10 times smaller, and a factor of 30 times or more cheaper. The ARC design is smaller than ITER, but it's still very much lower (a factor of 40) in power density than a fission reactor.
  - cromwellian 6y ago
    The power density isn't the only variable that matters. The difference doesn't matter if the cost to build a Thorium Molten Salt Reactor is much lower, especially in terms of safety and size. MSR's don't need enormous containment vessels, they also reprocess fuel. Here's some links showing power densities inline with PWRs, or greater: https://www.nextbigfuture.com/2013/12/molten-salt-reactor-about-50-times.html https://www.nextbigfuture.com/2013/12/molten-salt-reactor-ab... "Extrapolating from other liquid-to-liquid heat exchangers, roughly 150 MW/m3 is a practical upper limit to the power density of a primary-to-intermediate salt heat exchanger. For comparison, pressurized-water reactor core power density is ~110 MW/m3." https://info.ornl.gov/sites/publications/files/Pub29596.pdf https://info.ornl.gov/sites/publications/files/Pub29596.pdf
ncmncm 6y ago
The fact is, there is no reasonable expectation of ever getting viable commercial power from a tokamak-style fusion reactor. The density of energy production, in watts per cubic meter, is so low that an impractically large volume of confined plasma would be needed, requiring a reactor many times larger than a fission plant for the same power output. But fission-driven power is itself too expensive to produce to justify deploying on its own merits. Furthermore, since the power must be extracted by intercepting high-energy neutrons after they have blasted through the plasma focusing apparatus, such a plant would destroy its most expensive parts in a short time, requiring frequent rebuilding -- by robots, because of induced radioactivity at the work site. There has never been any expectation of practical commercial power resulting from plasma-confinement thermal-neutron fusion projects. Their only plausible budgetary justification is as a jobs program for high-neutron-flux physicists. They are called for by military policy as a population to draw personnel from for weapons work. Coal has always been cheaper than fission. Solar and wind power costs are much less, and continue falling; and numerous viable energy storage methods, all demanding no fundamental research -- gravity (solid and aqueous), underground and underwater compressed air, LH2, ammonia, methane from captured CO2, even powdered iron -- vie only for which will end up cheapest to deploy and operate. If a commercial reactor were ever built and made to work, it would take many decades just to break even on the money already spent to date, before bevinning to pay down its own construction -- even presuming it could find a market for its output. In practice, without continued public subsidy as long as it operated, its debt would continue to grow indefinitely. The only responsible course for the future is to cancel all publicly funded thermal-neutron fusion work, immediately.
- pfdietz 6y ago
  I think there is a slim chance that nuclear could remain relevant. The key would be greatly reducing the cost of the non-nuclear side of the power plant. Perhaps the best approach would be replacing large steam turbines with far more compact supercritical CO2 turbines. This would require temperatures somewhat higher than from PWRs. And this (not thorium, not waste destruction, nor really even safety) is perhaps the best argument for molten salt reactors.
  - 6y ago