5 ms·

Again this story. Ok, sure maybe it's smaller than a PWR behemoth. It's still solid fuel rod crap. If you have solid fuel rods, you have meltdown danger, you

Again this story. Ok, sure maybe it's smaller than a PWR behemoth. It's still solid fuel rod crap. If you have solid fuel rods, you have meltdown danger, you can't use up all the fissile material, there's no breeding, extraction of fission products. It's under a lot of pressure, so besides meltdown you have other dangers. Solid fuel rods can only use the very tiny percentage of uranium that is naturally fissile. This is simply not a good design for a nuclear reactor. The LFTR design has meltdown proof operation, no pressurized water, near 100% use of fuel, can burn/breed old solid fuel waste, can breed more fuel from plentiful thorium, and can scale down to closet-sized reactors. Pebble bed also shares some of these aspects, and I assume there are other new generation designs with advantages. But this is just more of the same bad design reactors. Oh great, it got spitshined and scaled down and passed approvals. What nuclear needs to be relevant is to tackle meltdown danger and nuclear waste. LFTR addresses both and any future reactor needs to address both. Perhaps LFTR could be a "waste processor" if LFTR isn't economical enough, while other meltdown proof designs do more economical generation in a sort of large scale web.

atwood22 4y ago
Are LFTRs actually viable though?
- AtlasBarfed 4y ago
  That's why I don't want to say "WE NEED TO USE LFTR". But the LFTR features are what we need in next gen nuclear: meltdown proof, full fuel use / vast waste reduction, scalable. Oak Ridge National Lab had a molten salt reactor that was closet-sized that they were working on. So it existed. Were all materials issues solved for a high temperature molten salt with all those neutrons flying around from breeding? No. China is (somewhat thankfully, why does fucking CHINA have to represent the major economic funding for solar, wind, batteries, and nuclear solutions to global warming?) bringing an MSR/LFTR online at utility scale in a couple years. But the point is I don't see nuclear being a viable solution unless it alleviates the Fukushima risk (unexpected meltdown) and the nuclear waste NIMBY issues. Scalability is necessary for economic viability.
  - formercoder 4y ago
    From what I have read waste storage is a non-problem from any practical view. It’s a really big planet. Just no one wants it in their little corner.
    - AtlasBarfed 4y ago
      The waste storage (Yucca mountain, find some geological scale safe place) would seem to, but again we run into the "old nuclear" view of things. Fukushima showed the flawed thinking that underpins "old nuclear": well, we have fixed the risks for everyday conditions ... that is, we put the minimum amount of required thought into safety from a political but not a fundamental design aspect. Waste TRANSPORT falls into this. Are we pretending that this isn't the transport of nuclear dirty bomb material? That's the fundamental issue. Sure it can be safe when it gets there, but the security of the waste in transport and the other dangers is just too high. I mean, a deer crossing the road could cause a crash and spill. Tire blowouts. etc. And there are just too many examples of corporations not giving a shit about truly dealing with environmental/waste/pollution procedures. Look at the fracking industry, they likely poisoned a great deal of water tables and other widespread effects, but didn't care in the least. They could get away with it. For waste storage, we can have some regulatory rubberstamp that "it is compliant" but all we need is some spill or something similar and you have nuclear waste in the water table. Great. Power generation and nuclear generation companies are full of conservative and environmental-hostile people. I don't know why this is, but it is, and it is another big issue with "old nuclear". I suspect it is a combination of the military origin of nuclear technology, regulatory fatigue, and the contempt of the Greenpeace antinuke types. But it is a fundamental organizational and culture problem of the nuclear industry. These organizations are hostile to the safety regulations and environmental concerns to the point that they will do the absolute minimum or backburner the risk mitigations. So that's why I view the LFTR's near-100% fuel use as a critical aspect of a next gen nuclear approach. It eliminates the problem of waste, and instead changes it to an efficiency challenge. There is no waste issue to deal with so it won't be down-prioritized on contemptuously viewed. No NIMBY issues on transport and storage.
      - 4y ago
bilsbie 4y ago
Couldn’t this be a stepping stone though? It seems to be a move in the right direction at least. Once costs come down they’ll be more investment in the tech you mentioned. Also this one does seem to have a good failsafe even though it has those risks.
rich_sasha 4y ago
Isn't corrosion from molten hot salt still an unresolved issue? Or at least a potential problem as big as loss of coolant in PWRs?
- Kalium 4y ago
  Same here, as far as I'm aware Thorium salt reactors are still solidly in the experimental stages. Demanding a switch to something that isn't ready yet strikes me as making perfection the enemy of better.
- pfdietz 4y ago
  There are lots of unresolved issues for MSRs. https://gain.inl.gov/SiteAssets/MoltenSaltReactor/Module2-OverviewofMSRTechnologyandConceptsML17331B114.pdf https://gain.inl.gov/SiteAssets/MoltenSaltReactor/Module2-Ov...
- abracadaniel 4y ago
  Unfortunately true. The molten salt solar concentrators couldn’t make it economical with a free source of heat. Replacing the heat source with a fission reaction only adds complexity to a system that’s already too difficult to maintain.
- AtlasBarfed 4y ago
  I'm definitely not saying LFTR has the materials solved. But liquid fuel leaks lead to immediate loss of neutron economy and the reaction stops. Solid fuel rods are always at risk of meltdown because once the solid fuel starts chain reacting out of control, you can't separate the fuel apart and stop the chain reaction. You're basically praying the moderators will slow it down. I believe pebble bed relies on small chunks of solid uranium, and if there is a meltdown risk, you separate the pebbles apart and like LFTR liquid safety pools and plugs, that kills the neutron economy and reactions stop. If the MSR vessel leaked from corrosion, it would likely fall into the safety pool and simply lose criticality. Anyway, I'm not advocating for LFTR to the exclusion of all other things. Just that solid fuel issues: lots of waste, meltdown danger, are just not palatable when there are designs and approaches that eliminate them. I don't care if it's "the only way that currently works", that is the "old guard" of nuclear protecting their current economic interests, not producing a nuclear design that is ACTUALLY next generation that will have relevance in a power generation ecosystem that will be dominated by solar, wind, and storage. Nuclear is already not price competitive. New nuclear projects will come online in 5-10 years in best case, and that's 5-10 years of wind/solar hitting economies of scale and research improvement (which are improving at 5-20% geometric improvements year on year), and battery storage is seeing high density LFP and sodium ion designs come into production. I simply view this approval as a rehash of old crappy design from the entrenched nuclear economic interests. Even with this rehash, it won't be remotely price competitive. Here's the thing with scalability and waste: If you scale it down, it's in a LOT more places, and then if you hae substantial waste generation, that is a LOT LOT LOT more transport issues and concerns with dirty bomb nuclear, crashes, accidents in transport. So that's why near-100% fuel use of LFTR is so important with scalability. Nuclear dismisses the NIMBYism, but the concerns over waste transport are real.
SECProto 4y ago
> Ok, sure maybe it's smaller than a PWR behemoth. It's still solid fuel rod crap. Yes, "solid fuel rod crap" same as used in every other production nuclear power plant? This SMR sounds like it might actually get built. One of the biggest issue that SMRs try to solve is the inability of (western) nations to build nuclear plants - which itself has myriad causes, but a big one is the difficulty in building any massive facility without cost and schedule overruns
- cma 4y ago
  ~~Few plants built after the non-proliferation treaty, because many plants were subsidized by proliferation needs.~~ (not true, see comments for correction) Nuclear plants don't even really pay insurance, they have $15 billion liability cap on the entire industry, when there are possible $1 trillion+ single incident disaster scenarios. Our first change should be that nuclear plants have to pay enough insurance to cover their full liability. Better to tax fossil than just hand out huge nuclear subsidies that risk safety. Let them both account for their risk and externalities individually. The Price Anderson Nuclear Indemnities Act was supposed to be temporary while the insurance industry for things stabilized: https://en.m.wikipedia.org/wiki/Price%E2%80%93Anderson_Nuclear_Industries_Indemnity_Act https://en.m.wikipedia.org/wiki/Price%E2%80%93Anderson_Nucle... > The act was intended to be temporary, and to expire in August 1967 as it was assumed that once the companies had demonstrated a record of safe operation they would be able to obtain insurance in the private market. There are some similar liability caps on oil spills and dam failures that should also be removed.
  - SECProto 4y ago
    > Few plants built after the non-proliferation treaty, because many plants were subsidized by proliferation needs. This is incorrect. Looking at the list[1], only 2 remaining reactors in Canada were built before the NPT was complete, and they're both scheduled to shut down in 2024. So essentially the entire Canadian nuke fleet was built after. Same thing for France. And Germany. For the US, also same - only a few that started construction before the 1968 signing remain working. Most operational plants started construction in the 1969-1976 range. [1] https://en.wikipedia.org/wiki/List_of_commercial_nuclear_reactors https://en.wikipedia.org/wiki/List_of_commercial_nuclear_rea...
credit_guy 4y ago
You know what killed nuclear power? The moving targets of the Nuclear Regulatory Commission. Was the NRC out to make life hard for new nuclear power plant construction? Some claim that, but I chose to believe that they were just doing their job. As more corner cases were discovered in the operation of the existing power plants, the regulations had to be upgraded to deal with them. This process will continue, that's for sure. But fewer corner cases will be discovered for PWRs than for new technologies. For the reason that in the US the experience with PWR is at least two orders of magnitude higher than with any other nuclear technology. Still, it took Nuscale 6 years to get their approval, 2 million man-hours and half a billion dollars. Whatever estimate they have for the time their first reactor goes online (2030 currently), it might be delayed because of new regulatory changes. But at least they have a proven design. If someone is trying a new design, the chance of delays increases one hundred times. I love new technology. I am personally rooting for the gas cooled fast reactors (like Xe-100) or for the sodium cooled fast reactors (like Terrapower's Natrium). But you need to walk before you run.
- formerly_proven 4y ago
  > You know what killed nuclear power? The moving targets of the Nuclear Regulatory Commission. Uh, massive political pushback from environmentalists starting in the 70s leading to less nuclear and more fossil fuel plants, because somehow they were (and continue to be in parts of the world) much more strongly and rigidly opposed to NPPs than coal and gas power plants.
  - pfdietz 4y ago
    That's not how it actually worked. What killed nuclear in the 1970s was a combination of things. First, NPPs turned out to be more expensive to build than vendors had promised. Second, electricity demand suddenly stopped growing as it had been. Third, PURPA passed, allowing non-utility producers onto the grid (ostensibly for cogeneration, although many were cogeneration in name only.) To the extent regulation bit nuclear, it was because of NEPA, which affects all industry not just nuclear. The AEC has tried pretend this didn't apply to nuclear but the Calvert Cliffs decision at SCOTUS said otherwise. 2+3 together meant utilities suddenly were in an environment where adding new GW capacity was a hard sell to state regulatory boards, and 1 made it even harder. Sure, environmentalists complained about nuclear, but don't infer that just because they complained, they caused nuclear to fail. Correlation != causation.
replygirl 4y ago
> What nuclear needs to be relevant is to tackle meltdown danger and nuclear waste. we already had the ingredients for that, but we cancelled yucca and a bunch of ap1ks
sradman 4y ago
> It's still solid fuel rod crap. There are a number of First-of-a-Kind SMR and Micro Reactors planned for the U.S., UK, and Canada. The advantage of the three leading lightwater SMRs (NuScale VOYGR, GE Hitachi BWRX-3000, and Rolls Royce SMR) are fast time to market due to the existing supply chain and continuous innovation on well understood technology. The problem is not so much the solid fuel, but the Zirconium clad fuel bundles that produce explosive hydrogen gas during Loss-of-Coolant-Accidents (LOCA). Accident Tolerant Fuels are being deployed now and may be another important innovation that reduces the likelihood of meltdowns but these systems also address the main sources of LOCAs: 1. isolation condenser system (ICS) replace pressure release valves that caused the Three Mile Island accident, and 2. passive coolant circulation systems that don't require external/backup power like the ones that failed during the Fukushima accident. The problem with this class of lightwater SMR is that they are essentially base load power and the projected Nth-of-a-Kind costs will be competitive with fossil fuels (coal and natural gas) at best but are not cost competitive nor a good complement to intermittent renewables (wind and solar). They are a good slot-in replacement for existing coal fired plants. There are also a number of Advanced SMRs and Micro Reactors (mobile and campus-size) that have announced First-of-a-Kind builds like the X-Energy Xe-100, TerraPower/GE Hitachi Natrium, ARC-100, Moltex SSR-W, USNC MMR, Xe-Mobile, and Westinghouse eVinci. These designs compete on a much larger landscape of theoretical trade-offs that may leapfrog the lightwater SMRs. I prefer this diverse mix of technologies and applications over a single anointed technology like Liquid fluoride thorium reactors (LFTRs). YMMV.

atwood22 4y ago

Are LFTRs actually viable though?

AtlasBarfed 4y ago
That's why I don't want to say "WE NEED TO USE LFTR". But the LFTR features are what we need in next gen nuclear: meltdown proof, full fuel use / vast waste reduction, scalable. Oak Ridge National Lab had a molten salt reactor that was closet-sized that they were working on. So it existed. Were all materials issues solved for a high temperature molten salt with all those neutrons flying around from breeding? No. China is (somewhat thankfully, why does fucking CHINA have to represent the major economic funding for solar, wind, batteries, and nuclear solutions to global warming?) bringing an MSR/LFTR online at utility scale in a couple years. But the point is I don't see nuclear being a viable solution unless it alleviates the Fukushima risk (unexpected meltdown) and the nuclear waste NIMBY issues. Scalability is necessary for economic viability.
- formercoder 4y ago
  From what I have read waste storage is a non-problem from any practical view. It’s a really big planet. Just no one wants it in their little corner.
  - AtlasBarfed 4y ago
    The waste storage (Yucca mountain, find some geological scale safe place) would seem to, but again we run into the "old nuclear" view of things. Fukushima showed the flawed thinking that underpins "old nuclear": well, we have fixed the risks for everyday conditions ... that is, we put the minimum amount of required thought into safety from a political but not a fundamental design aspect. Waste TRANSPORT falls into this. Are we pretending that this isn't the transport of nuclear dirty bomb material? That's the fundamental issue. Sure it can be safe when it gets there, but the security of the waste in transport and the other dangers is just too high. I mean, a deer crossing the road could cause a crash and spill. Tire blowouts. etc. And there are just too many examples of corporations not giving a shit about truly dealing with environmental/waste/pollution procedures. Look at the fracking industry, they likely poisoned a great deal of water tables and other widespread effects, but didn't care in the least. They could get away with it. For waste storage, we can have some regulatory rubberstamp that "it is compliant" but all we need is some spill or something similar and you have nuclear waste in the water table. Great. Power generation and nuclear generation companies are full of conservative and environmental-hostile people. I don't know why this is, but it is, and it is another big issue with "old nuclear". I suspect it is a combination of the military origin of nuclear technology, regulatory fatigue, and the contempt of the Greenpeace antinuke types. But it is a fundamental organizational and culture problem of the nuclear industry. These organizations are hostile to the safety regulations and environmental concerns to the point that they will do the absolute minimum or backburner the risk mitigations. So that's why I view the LFTR's near-100% fuel use as a critical aspect of a next gen nuclear approach. It eliminates the problem of waste, and instead changes it to an efficiency challenge. There is no waste issue to deal with so it won't be down-prioritized on contemptuously viewed. No NIMBY issues on transport and storage.
    - 4y ago

bilsbie 4y ago

Couldn’t this be a stepping stone though? It seems to be a move in the right direction at least. Once costs come down they’ll be more investment in the tech you mentioned. Also this one does seem to have a good failsafe even though it has those risks.

rich_sasha 4y ago

Isn't corrosion from molten hot salt still an unresolved issue? Or at least a potential problem as big as loss of coolant in PWRs?

Kalium 4y ago
Same here, as far as I'm aware Thorium salt reactors are still solidly in the experimental stages. Demanding a switch to something that isn't ready yet strikes me as making perfection the enemy of better.
pfdietz 4y ago
There are lots of unresolved issues for MSRs. https://gain.inl.gov/SiteAssets/MoltenSaltReactor/Module2-OverviewofMSRTechnologyandConceptsML17331B114.pdf https://gain.inl.gov/SiteAssets/MoltenSaltReactor/Module2-Ov...
abracadaniel 4y ago
Unfortunately true. The molten salt solar concentrators couldn’t make it economical with a free source of heat. Replacing the heat source with a fission reaction only adds complexity to a system that’s already too difficult to maintain.
AtlasBarfed 4y ago
I'm definitely not saying LFTR has the materials solved. But liquid fuel leaks lead to immediate loss of neutron economy and the reaction stops. Solid fuel rods are always at risk of meltdown because once the solid fuel starts chain reacting out of control, you can't separate the fuel apart and stop the chain reaction. You're basically praying the moderators will slow it down. I believe pebble bed relies on small chunks of solid uranium, and if there is a meltdown risk, you separate the pebbles apart and like LFTR liquid safety pools and plugs, that kills the neutron economy and reactions stop. If the MSR vessel leaked from corrosion, it would likely fall into the safety pool and simply lose criticality. Anyway, I'm not advocating for LFTR to the exclusion of all other things. Just that solid fuel issues: lots of waste, meltdown danger, are just not palatable when there are designs and approaches that eliminate them. I don't care if it's "the only way that currently works", that is the "old guard" of nuclear protecting their current economic interests, not producing a nuclear design that is ACTUALLY next generation that will have relevance in a power generation ecosystem that will be dominated by solar, wind, and storage. Nuclear is already not price competitive. New nuclear projects will come online in 5-10 years in best case, and that's 5-10 years of wind/solar hitting economies of scale and research improvement (which are improving at 5-20% geometric improvements year on year), and battery storage is seeing high density LFP and sodium ion designs come into production. I simply view this approval as a rehash of old crappy design from the entrenched nuclear economic interests. Even with this rehash, it won't be remotely price competitive. Here's the thing with scalability and waste: If you scale it down, it's in a LOT more places, and then if you hae substantial waste generation, that is a LOT LOT LOT more transport issues and concerns with dirty bomb nuclear, crashes, accidents in transport. So that's why near-100% fuel use of LFTR is so important with scalability. Nuclear dismisses the NIMBYism, but the concerns over waste transport are real.

SECProto 4y ago

> Ok, sure maybe it's smaller than a PWR behemoth. It's still solid fuel rod crap. Yes, "solid fuel rod crap" same as used in every other production nuclear power plant? This SMR sounds like it might actually get built. One of the biggest issue that SMRs try to solve is the inability of (western) nations to build nuclear plants - which itself has myriad causes, but a big one is the difficulty in building any massive facility without cost and schedule overruns

cma 4y ago
~~Few plants built after the non-proliferation treaty, because many plants were subsidized by proliferation needs.~~ (not true, see comments for correction) Nuclear plants don't even really pay insurance, they have $15 billion liability cap on the entire industry, when there are possible $1 trillion+ single incident disaster scenarios. Our first change should be that nuclear plants have to pay enough insurance to cover their full liability. Better to tax fossil than just hand out huge nuclear subsidies that risk safety. Let them both account for their risk and externalities individually. The Price Anderson Nuclear Indemnities Act was supposed to be temporary while the insurance industry for things stabilized: https://en.m.wikipedia.org/wiki/Price%E2%80%93Anderson_Nuclear_Industries_Indemnity_Act https://en.m.wikipedia.org/wiki/Price%E2%80%93Anderson_Nucle... > The act was intended to be temporary, and to expire in August 1967 as it was assumed that once the companies had demonstrated a record of safe operation they would be able to obtain insurance in the private market. There are some similar liability caps on oil spills and dam failures that should also be removed.
- SECProto 4y ago
  > Few plants built after the non-proliferation treaty, because many plants were subsidized by proliferation needs. This is incorrect. Looking at the list[1], only 2 remaining reactors in Canada were built before the NPT was complete, and they're both scheduled to shut down in 2024. So essentially the entire Canadian nuke fleet was built after. Same thing for France. And Germany. For the US, also same - only a few that started construction before the 1968 signing remain working. Most operational plants started construction in the 1969-1976 range. [1] https://en.wikipedia.org/wiki/List_of_commercial_nuclear_reactors https://en.wikipedia.org/wiki/List_of_commercial_nuclear_rea...

credit_guy 4y ago

You know what killed nuclear power? The moving targets of the Nuclear Regulatory Commission. Was the NRC out to make life hard for new nuclear power plant construction? Some claim that, but I chose to believe that they were just doing their job. As more corner cases were discovered in the operation of the existing power plants, the regulations had to be upgraded to deal with them. This process will continue, that's for sure. But fewer corner cases will be discovered for PWRs than for new technologies. For the reason that in the US the experience with PWR is at least two orders of magnitude higher than with any other nuclear technology. Still, it took Nuscale 6 years to get their approval, 2 million man-hours and half a billion dollars. Whatever estimate they have for the time their first reactor goes online (2030 currently), it might be delayed because of new regulatory changes. But at least they have a proven design. If someone is trying a new design, the chance of delays increases one hundred times. I love new technology. I am personally rooting for the gas cooled fast reactors (like Xe-100) or for the sodium cooled fast reactors (like Terrapower's Natrium). But you need to walk before you run.

formerly_proven 4y ago
> You know what killed nuclear power? The moving targets of the Nuclear Regulatory Commission. Uh, massive political pushback from environmentalists starting in the 70s leading to less nuclear and more fossil fuel plants, because somehow they were (and continue to be in parts of the world) much more strongly and rigidly opposed to NPPs than coal and gas power plants.
- pfdietz 4y ago
  That's not how it actually worked. What killed nuclear in the 1970s was a combination of things. First, NPPs turned out to be more expensive to build than vendors had promised. Second, electricity demand suddenly stopped growing as it had been. Third, PURPA passed, allowing non-utility producers onto the grid (ostensibly for cogeneration, although many were cogeneration in name only.) To the extent regulation bit nuclear, it was because of NEPA, which affects all industry not just nuclear. The AEC has tried pretend this didn't apply to nuclear but the Calvert Cliffs decision at SCOTUS said otherwise. 2+3 together meant utilities suddenly were in an environment where adding new GW capacity was a hard sell to state regulatory boards, and 1 made it even harder. Sure, environmentalists complained about nuclear, but don't infer that just because they complained, they caused nuclear to fail. Correlation != causation.

replygirl 4y ago

> What nuclear needs to be relevant is to tackle meltdown danger and nuclear waste. we already had the ingredients for that, but we cancelled yucca and a bunch of ap1ks

sradman 4y ago

> It's still solid fuel rod crap. There are a number of First-of-a-Kind SMR and Micro Reactors planned for the U.S., UK, and Canada. The advantage of the three leading lightwater SMRs (NuScale VOYGR, GE Hitachi BWRX-3000, and Rolls Royce SMR) are fast time to market due to the existing supply chain and continuous innovation on well understood technology. The problem is not so much the solid fuel, but the Zirconium clad fuel bundles that produce explosive hydrogen gas during Loss-of-Coolant-Accidents (LOCA). Accident Tolerant Fuels are being deployed now and may be another important innovation that reduces the likelihood of meltdowns but these systems also address the main sources of LOCAs: 1. isolation condenser system (ICS) replace pressure release valves that caused the Three Mile Island accident, and 2. passive coolant circulation systems that don't require external/backup power like the ones that failed during the Fukushima accident. The problem with this class of lightwater SMR is that they are essentially base load power and the projected Nth-of-a-Kind costs will be competitive with fossil fuels (coal and natural gas) at best but are not cost competitive nor a good complement to intermittent renewables (wind and solar). They are a good slot-in replacement for existing coal fired plants. There are also a number of Advanced SMRs and Micro Reactors (mobile and campus-size) that have announced First-of-a-Kind builds like the X-Energy Xe-100, TerraPower/GE Hitachi Natrium, ARC-100, Moltex SSR-W, USNC MMR, Xe-Mobile, and Westinghouse eVinci. These designs compete on a much larger landscape of theoretical trade-offs that may leapfrog the lightwater SMRs. I prefer this diverse mix of technologies and applications over a single anointed technology like Liquid fluoride thorium reactors (LFTRs). YMMV.