3 ms·

What's the advantage? It's higher burnup and higher efficiency, but the enrichment % more than cancels that out. Is it just that there's no containment vessel?

credit_guy 4y ago
Higher burnup, higher efficiency, and higher enrichment means less waste. Much less waste. Higher enrichment is the opposite of "cancels that out". Maybe you are thinking in terms of cost, but the cost of enrichment is negligible compared to the energy produced. In terms of waste, there will be at least 4 times less waste per unit of energy produced (thermal energy is about twice as high as for a PWR reactor and the enrichment is also about twice as high). Another advantage is the fact this is a Small Modular Reactor. China wants to build 18 by the end of the decade. That is iteration. That's how you drive the cost down. SpaceX is said to build one Raptor per day. Even without reusable boosters, just this pace of iteration means their workers and processes became much more efficient at building the engines. With a bit of googling around you can find the cost of a Raptor is 5-10 times lower than the cost of comparable engines, per unit of thrust. It is very likely this cost advantage will only increase going forward.
- Schroedingersat 4y ago
  > Higher burnup, higher efficiency, and higher enrichment means less waste. Much less waste. No it doesn't. The really bad waste (because it outmasses the rest by four orders of magnitude) is in a tailings pond that will be 'remediated' by pulling a plastic sheet over it in Namibia, or being pumped into the ground water in Kazakhstan, or spilled onto the farm land in Navajo. Higher enrichment means more of that. Reducing high grade waste by 20% at the cost of doubling that seems like a step backwards. Don't you keep saying the amount of high grade waste is completely insignificant? How would reducing something completely insignificant help? It'd be like touting a new solar panel using half the boron dopant reducing it to a microgram at the expense of using 10x as much silver as a nuclear plant rather than 5x. > Another advantage is the fact this is a Small Modular Reactor. China wants to build 18 by the end of the decade. That is iteration. That's how you drive the cost down. How much does fabricating the microspheres and then the pebbles cost? How much does de-fabricating them to achieve 'less waste' cost? I seem to have found the actual upside. It's designed to be a drop in replacement on a coal generator. This makes sense and reduces radioactive waste slightly (or rather puts it in the ground in Niger rather than the air in china).
  - credit_guy 4y ago
    > The really bad waste (because it outmasses the rest by four orders of magnitude) is in a tailings pond that will be 'remediated' by pulling a plastic sheet over it in Namibia. If it outmasses the others by four orders of magnitude, it means on average from each 10000 tons of dirt we extract 1 ton of Uranium, right? And we are left with 9999 tons of the original dirt. Why is that dirt so bad? If anything it has less Urnanium in it, not more. It can't be more radioactive than the thing it initially was, can it?
    - Schroedingersat 4y ago
      Because granite isn't water soluble. Because you've taken rocks that were safely underground with heavy metals safely locked in stable oxides, released all the accumulated radon, and poured 1000 tons of sulfuric acid on it to extract 10 tons of Uranium which you will use 1 ton of for fuel. The toxic slurry is then left in a poorly maintained pond which leaks into farm land where all the other poisonous elements (some of which are also radioactive) bioaccumulate into food. https://en.m.wikipedia.org/wiki/Church_Rock_uranium_mill_spill https://en.m.wikipedia.org/wiki/Church_Rock_uranium_mill_spi... https://timesofindia.indiatimes.com/city/amaravati/uranium-tailings-pond-in-kadapa-not-fenced-panel/articleshow/71318886.cms https://timesofindia.indiatimes.com/city/amaravati/uranium-t... In ISL they just let the toxic sulfuric acid slurry soak into the ground water and objections of hydrology engineers pointing out that most of the ISL mines don't meet the very specific conditions that keep it contained are met with 'it attenuates' with no further discussion or scientific evidence. This is in addition to the decomissioning and other low level or non-radioactive waste which is more than the solar panels even if they aren't recycled. Nuclear is not clean. It just puts the filth elsewhere. Similarly solar and wind aren't clean, but they are significantly better over all and are rapidly improving. This is why step one is reduction. A very cheap drop in replacement for a coal boiler would be a good thing, but it's not a panacea and it's not an alternative to renewable energy -- merely a step towards it. MSRs or LFTRs might be, but there's no indication they're achievable, and the mining involved for current liquid salt concepts is even worse (beryllium). Plus the odds the 7 or so nuclear countries would let anyone else have plutonium breeding capability are effectively nil, so it's not a global solution anyway.

credit_guy 4y ago

Higher burnup, higher efficiency, and higher enrichment means less waste. Much less waste. Higher enrichment is the opposite of "cancels that out". Maybe you are thinking in terms of cost, but the cost of enrichment is negligible compared to the energy produced. In terms of waste, there will be at least 4 times less waste per unit of energy produced (thermal energy is about twice as high as for a PWR reactor and the enrichment is also about twice as high). Another advantage is the fact this is a Small Modular Reactor. China wants to build 18 by the end of the decade. That is iteration. That's how you drive the cost down. SpaceX is said to build one Raptor per day. Even without reusable boosters, just this pace of iteration means their workers and processes became much more efficient at building the engines. With a bit of googling around you can find the cost of a Raptor is 5-10 times lower than the cost of comparable engines, per unit of thrust. It is very likely this cost advantage will only increase going forward.

Schroedingersat 4y ago
> Higher burnup, higher efficiency, and higher enrichment means less waste. Much less waste. No it doesn't. The really bad waste (because it outmasses the rest by four orders of magnitude) is in a tailings pond that will be 'remediated' by pulling a plastic sheet over it in Namibia, or being pumped into the ground water in Kazakhstan, or spilled onto the farm land in Navajo. Higher enrichment means more of that. Reducing high grade waste by 20% at the cost of doubling that seems like a step backwards. Don't you keep saying the amount of high grade waste is completely insignificant? How would reducing something completely insignificant help? It'd be like touting a new solar panel using half the boron dopant reducing it to a microgram at the expense of using 10x as much silver as a nuclear plant rather than 5x. > Another advantage is the fact this is a Small Modular Reactor. China wants to build 18 by the end of the decade. That is iteration. That's how you drive the cost down. How much does fabricating the microspheres and then the pebbles cost? How much does de-fabricating them to achieve 'less waste' cost? I seem to have found the actual upside. It's designed to be a drop in replacement on a coal generator. This makes sense and reduces radioactive waste slightly (or rather puts it in the ground in Niger rather than the air in china).
- credit_guy 4y ago
  > The really bad waste (because it outmasses the rest by four orders of magnitude) is in a tailings pond that will be 'remediated' by pulling a plastic sheet over it in Namibia. If it outmasses the others by four orders of magnitude, it means on average from each 10000 tons of dirt we extract 1 ton of Uranium, right? And we are left with 9999 tons of the original dirt. Why is that dirt so bad? If anything it has less Urnanium in it, not more. It can't be more radioactive than the thing it initially was, can it?
  - Schroedingersat 4y ago
    Because granite isn't water soluble. Because you've taken rocks that were safely underground with heavy metals safely locked in stable oxides, released all the accumulated radon, and poured 1000 tons of sulfuric acid on it to extract 10 tons of Uranium which you will use 1 ton of for fuel. The toxic slurry is then left in a poorly maintained pond which leaks into farm land where all the other poisonous elements (some of which are also radioactive) bioaccumulate into food. https://en.m.wikipedia.org/wiki/Church_Rock_uranium_mill_spill https://en.m.wikipedia.org/wiki/Church_Rock_uranium_mill_spi... https://timesofindia.indiatimes.com/city/amaravati/uranium-tailings-pond-in-kadapa-not-fenced-panel/articleshow/71318886.cms https://timesofindia.indiatimes.com/city/amaravati/uranium-t... In ISL they just let the toxic sulfuric acid slurry soak into the ground water and objections of hydrology engineers pointing out that most of the ISL mines don't meet the very specific conditions that keep it contained are met with 'it attenuates' with no further discussion or scientific evidence. This is in addition to the decomissioning and other low level or non-radioactive waste which is more than the solar panels even if they aren't recycled. Nuclear is not clean. It just puts the filth elsewhere. Similarly solar and wind aren't clean, but they are significantly better over all and are rapidly improving. This is why step one is reduction. A very cheap drop in replacement for a coal boiler would be a good thing, but it's not a panacea and it's not an alternative to renewable energy -- merely a step towards it. MSRs or LFTRs might be, but there's no indication they're achievable, and the mining involved for current liquid salt concepts is even worse (beryllium). Plus the odds the 7 or so nuclear countries would let anyone else have plutonium breeding capability are effectively nil, so it's not a global solution anyway.