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I get the fascination with base load and the incredible amount of energy compared to chemical based alternatives. But: 1. What will the net online time be? (Lot

by eecc 5y ago

I get the fascination with base load and the incredible amount of energy compared to chemical based alternatives. But: 1. What will the net online time be? (Lots of these plants go in maintenance for long stretches of time) 2. Spent fuel? 3. Proliferation risk? 4. Accident mitigation?

funklute 5y ago
None of those questions are new, nor show stoppers for existing plants. Why do you think the existing procedures may not be satisfactory? (I'm assuming you think so based on the way you ask the question) EDIT: to be clear, I'm not asking this as a backhanded question. I'm genuinely curious why this is not seen as a "solved problem", at least in a country with relatively strong government institutions
- eecc 5y ago
  Well, the way previous generations fizzled suggests these problems aren’t that solved after all. Just 1 long term waste storage has ever been built in the world, plant productivity has always been relatively low (initial manufacturing delays, refueling, minor accidents, refurbishments), many anti-proliferation techniques just over-produce rad-waste. Oh, and if we were to buildout nuclear globally how long would the ore reserves last?
  - R0b0t1 5y ago
    It fizzled due to FUD. Existing plants work and are defensible. The waste can be stored safely. In emerging economies new designs can be used, but they'll probably have to be trialed in a developed economy. You could also pursue economic policy that has developing economies fund the research instead of letting them expect handouts.
    - wolverine876 5y ago
      > It fizzled due to FUD. You're saying there were no actual, serious problems with nuclear plants? > Existing plants work and are defensible. That's survivorship bias to a degree: Te plants that work and are defensible are the plants you see. It's also a bias of sunk costs: The surviving plants could have been way over-budget and late, but it's still worth operating them.
      - vkou 5y ago
        > You're saying there were no actual, serious problems with nuclear plants? Compared to other forms of energy generation, measured in illnesses, injuries, maimings, and deaths, past and plausibly attributed to the future, per KWH? Not really, no.
        wolverine876 5y ago
        I tire of the 'say something bold and prove me wrong' rhetoric, when people know exactly what's wrong with what they are saying. It doesn't contribute to anyone's understanding, and wastes my time. Hope the rest of your day goes well.
        vkou 5y ago
        The realization that industrial processes are dangerous, that power generation is an industrial process, and therefore dangerous, and that the only meaningful way to measure the danger of an industrial process is by comparing it to that of another industrial process should contribute to the understanding of some. Is nuclear power generation dangerous? Yes. Is all power generation dangerous? Yes. How dangerous is nuclear power generation compared to alternatives? Not very. It's pretty accurate to say that nuclear fizzled due to FUD. The conversation ended after the answer to the first question was 'yes'.
        johncolanduoni 5y ago
        I’d appreciate if you could clarify what’s wrong. Even if both you and your interlocutor understand it, the point has unfortunately gone over my head (and possibly the same for others reading).
        consumer451 5y ago
        Not OP, but one problem that they mentioned which is "wrong" from an economic point of view is that afaik, there is no way to calculate the total cost of ownership of a nuclear plant. This is due to that fact that there are no viable plans for long term nuclear storage to calculate the cost of. Is this not "wrong" in a very material way?
  - blendergeek 5y ago
    > Oh, and if we were to buildout nuclear globally how long would the ore reserves last? If we fully burn all available nuclear fuel, it will last about 5 billion years. [0] [0] https://web.archive.org/web/20130114062518/http://sustainablenuclear.org/PADs/pad11983cohen.pdf https://web.archive.org/web/20130114062518/http://sustainabl...
    - eecc 5y ago
      Ah that’s breeders, it’s a different game. They’re technically more challenging (the French spent billions on their plants which didn't quite deliver) and have a significant nuclear weapons proliferation risk. Somewhere I read (sorry for the lack of sources) that with single-pass fuel use, known reserves would only last a couple decades, a century at best.
      - effie 5y ago
        > have a significant nuclear weapons proliferation risk. Why. What risk of proliferation is there in France, UK or U.S.? These states already have nuclear weapons.
        onecommentman 5y ago
        A global buildout of breeders is the issue. The rich countries telling the poor countries they can’t have nice things because of “our” security concerns. Big talking point in the 1960s. Tom Lehrer even wrote a cute song about nuclear proliferation in 1964, “Who’s Next?”. If you get any expansive policy and process wrong, the negative global consequences are dramatic and long-lasting. So, first, do no harm.
user_7832 5y ago
I can try to answer your questions. (Disclaimer, I'm a masters student studying systems with a focus on energy systems. Obviously not an expert, and am somewhat biased pro-nuclear.) 1. Net online time for nuclear isn't particularly bad, especially when you consider that other alternatives too go down. [1] Of course you'll need some extra capacity/more plants, but that was anyway the case. 2. I feel this is probably the strongest point that can be held against nuclear. Short-term fuel management is not an issue/already figured out, and climate change is a much quicker risk in the next 50 years, so I'd argue it's still better to go 0-carbon instead of finding a perfect solution right now. 3. I'm not sure if you're referring to proliferation of the fuel or technologies, but both are reasonably well-developed fields that France should not have major problems. 4. Similar to point one - nuclear accidents vs risks/deaths from coal is like comparing flight safety with cars. Sure, airplanes feel unsafe but are statistically MUCH safer than cars. Chernobyl and Fukushima were both avoidable (though that can admitably be said for a lot of accidents). Deaths from pollution itself are in the millions instead. [2] 1. https://www.energy.gov/ne/articles/nuclear-power-most-reliable-energy-source-and-its-not-even-close https://www.energy.gov/ne/articles/nuclear-power-most-reliab... 2. https://ourworldindata.org/safest-sources-of-energy https://ourworldindata.org/safest-sources-of-energy
- majou 5y ago
  Proliferation in the context of nuclear is the risk of terrorists or states intercepting fuel that can be refined to weapon-grade. Some reactors don't have this risk, but I'm not read on it.
  - ineedasername 5y ago
    Decades with hundred of nuclear power plants in the world have not seen them be a significant source of fissionable material for terrorists or new nations developing nuclear weapons. See Iran, a nation that has devoted significant resources to such an endeavor, as a case in point. Spent fuel from nuclear power plants-- probably the more vulnerable point in the supply chain-- is nonetheless difficult to the point of extreme expense & impractical to refine to weapons grade. You would need such large quantities that it would be extremely difficult to steal enough without notice: Someone is going to notice the 200,000 lb cask leaving a storage facility. Then the refinement process is difficult, requiring immense sums of money to built the significant infrastructure required for refinement. North Korea, the newest nuclear power, got there with significant help from the Soviets extending back in the 60's and it still took them decades to get there. This is all on top of the fact that any modern plant designs use feedstock fuel that is even harder to refine into anything weapons grade, and is much more efficient to the point that spend fuel refinement difficulties dwarfs the above roadblocks for fuel from older designs. Dirty bombs are more problematic, but also significantly less destructive, and suffer from many of the same logistical hurdles, notably that the material most useful for a dirty bomb is also material that requires massively robust precautions to ensure the thieves don't kill themselves with radiation exposure long before any chance of making use of it. Less useful material that requires fewer precautions is not practical for dirty bombs without significant refinement capacity. All of this at a time when real measurable deaths from fossil fuel powerplants, their pollution, and their industrial accidents, are themselves more dangerous, right now, than theoretical & difficult to achieve usages of fuel from new nuclear power plants.
axlee 5y ago
France has been running on 75%+ nuclear power mix for the past 50 years and is doing better energy/emissions-wise than almost every other country in the world. Your questions have already been answered, it seems. They seem to have bet on the right horse, and went full steam ahead with it (no pun intended). And now they are supplying all their neighbours with surplus clean energy.
- stjohnswarts 5y ago
  I always point at this when my American "environmental" friends yell at me as a proponent of a Manhattan style project in nuclear tech here in the USA as the solution to climate change.
  - throw0101a 5y ago
    See also the province of Ontario ("Supply" tab): * https://www.ieso.ca/power-data https://www.ieso.ca/power-data
monocasa 5y ago
France has significantly less spent fuel to deal with since they allow civilian energy production to reprocess spent fuel back into usable fuel.
- eecc 5y ago
  True, but breeder technology has a lot more potential for weaponry proliferation (part of the reason France is so much invested in nuclear is precisely because of that.) And it’s not as easy as recycling empty glass bottles… the French struggled to keep their breeders online and keep them economical (but then the military we’re still happy so…)
godelski 5y ago
> 1. What will the net online time be? Hard to say tbh. But these reactors probably aren't offline as much as you think. They shut down for 1 month every 18-24 months for refueling. > 2. Spent fuel? France is the world leader in this regard. Remember that 17% of France's entire power comes from _recycled_ nuclear. But if you want to see what their entire nuclear waste. This is _decades_ worth, and I'm betting much smaller than you expected.[0] (coal is doing this on a a daily or weekly basis). Just for fun, let's look at Russia's too.[1] We're literally just talking a warehouse. People vastly overestimate the waste and what to do with it. It is fine where it is for hundreds of years. The only "problem" that we have with "long term storage" is how to store it somewhere where if somehow all knowledge was lost that future humans with no radiation detecting equipment could accidentally release waste (quite a high bar, and not one we're concerned with other long lasting waste like lead or heavy metals). We have a few hundred years to figure that out. > 3. Proliferation risk? None? It is France. They already have nuclear weapons. But while we're talking about it, Megatons to Megawatts[2] has been the best deproliferation project in history, reducing the number of nuclear warheads by over 20,000. > 4. Accident mitigation? Very low. This is also over estimated. We have a very early reactor which no other country besides Russia built because it had the ability to explode. And we have another event where we didn't know earthquakes could happen of that size until basically right before said earthquake happened. These are major disasters, but the two should not be conflated. Even including these, they are far less environmentally damaging than the fossil fuels we've been using. The major problem with nuclear is that disasters are both temporally and spatially localized. There's advantages and disadvantages to this in terms of dealing with the consequences. On one hand, it is a lot to clean up. On the other hand the country that created the disaster is the one that suffers the most (as opposed to what we're seeing with oil spills and the entire climate crisis, which is not temporally localized and thus the danger is not weighted properly). [0] https://twitter.com/Orano_usa/status/1182662569619795968 https://twitter.com/Orano_usa/status/1182662569619795968 [1] https://www.youtube.com/watch?v=_5uN0bZBOic&t=105s https://www.youtube.com/watch?v=_5uN0bZBOic&t=105s [2] https://en.wikipedia.org/wiki/Megatons_to_Megawatts_Program https://en.wikipedia.org/wiki/Megatons_to_Megawatts_Program
- wolverine876 5y ago
  >> 3. Proliferation risk? > None? It is France. They already have nuclear weapons. But while we're talking about it, Megatons to Megawatts[2] has been the best deproliferation project in history, reducing the number of nuclear warheads by over 20,000. More nuclear trained personnel, designs, materials, and plants mean more opportunities for someone to acquire technology or materials.
Manuel_D 5y ago
1. What will the net online time be? (Lots of these plants go in maintenance for long stretches of time) The term you're referring to is capacity factor. Nuclear power typically has the highest capacity factor of any energy source. [1] [2] For reference, nuclear is 92%, while wind is 35% and photovoltaic solar at 25%. > 2. Spent fuel? It can be reprocessed, reclaiming over 90% of fuel. Even without reprocessing, nuclear fuel's energy density is such that a tiny amount of waste is produced per unit of energy. For comparison, the sum total of all of the USA's nuclear electricity production occupies a volume the footprint of a football field, and 10 yards high. [3] > 3. Proliferation risk? Nuclear fuel is refined to about ~20% fissile material. Nuclear weapons typically need over 80% or 90%. Countries would need to build their own enrichment facilities to bring nuclear fuel to weapons grade uranium, and then further refine that to plutonium. If they had such facilities they'd be able to refine natural uranium to weapons grade anyway. > 4. Accident mitigation? First of all, even if you include Chernobyl nuclear power (which didn't even have secondary storage) has the lowest fatalities per unit of energy produced [4]. People often neglect the fact that fossil fuels kill millions each year due to air pollution. Renewables like hydroelectricity have had accidents far more devastating that nuclear power [5]. Nuclear plants are expensive because a lot of effort is made to make them safe, and to contain a potential failure. People often forget that the USA had a reactor meltdown analogous to Chernobyl during the Three Mile Island incident. Except nobody died and there was no widespread contamination because the reactor had a big concrete condom over it, unlike Chernobyl. 1. https://www.statista.com/statistics/183680/us-average-capacity-factors-by-selected-energy-source-since-1998/ https://www.statista.com/statistics/183680/us-average-capaci... 2. https://en.wikipedia.org/wiki/Capacity_factor#Worldwide https://en.wikipedia.org/wiki/Capacity_factor#Worldwide 3. https://www.energy.gov/ne/articles/5-fast-facts-about-spent-nuclear-fuel https://www.energy.gov/ne/articles/5-fast-facts-about-spent-... 4. https://www.statista.com/statistics/494425/death-rate-worldwide-by-energy-source/ https://www.statista.com/statistics/494425/death-rate-worldw... 5. https://en.wikipedia.org/wiki/1975_Banqiao_Dam_failure https://en.wikipedia.org/wiki/1975_Banqiao_Dam_failure
- wolverine876 5y ago
  > Nuclear fuel is refined to about ~20% fissile material. Nuclear weapons typically need over 80% or 90%. Countries would need to build their own enrichment facilities to bring nuclear fuel to weapons grade uranium, and then further refine that to plutonium. If they had such facilities they'd be able to refine natural uranium to weapons grade anyway. I've wondered about that. On one hand, the reasoning above makes sense. On the other, people who know far more than I do say there is proliferation risk. I suspect there is something I don't understand.
BiteCode_dev 5y ago
1 - During my study, I visited a nuclear plant. They explained to us the plant is designed around 4 quadrants, each one capable of turning on and off independently of each other. So when one needs maintenance, you just put this one offline, and the others keep running. This way the reactor is never totally shut off, as I understand that starting it from scratch is an expensive operation. 2 - For the spent fuel, France has plenty of strategically maintained relationships in what used to be West African colonies with uranium mines. Why do you think we sent the army during the Mali war ? We cultivate those alliances because they bring a lot on the table, from resources to routes and bases. Nuclear is doubly interesting for us, because we can source it even if Russia or China decide to tell us to go to hell. In case of a conflict, this is priceless. 3 - I don't know anything about proliferation, so can't answer this one. 4 - Accident mitigation is the big problem, IMO. I've seen how they operate inside, and let's just say I'm glad the people that designed the thing were very, very, _very_ good at their job. Because the ones maintaining it have a very relaxed attitude. And the plants are pushed to produce way past their initial expected life span. But I insist, I'm amazed at how good engineers of the 70' were. Those plants are old tech, but they are incredible. However, even if the probability of an accident is low (there are triple safety mechanisms everywhere), the severity of a potential accident is such that I consider nuclear disasters a huge risk that we don't take seriously enough. What's more, it nourishes the growing anti-nuclear sentiment, so we should really get our act together.
- enaaem 5y ago
  The risks of nuclear energy is far more favourable than global warming. Global warming effects are global, non-linear and there are still many unknowns, which makes it more risky. Nuclear risks are local and the harm is well known. Also nuclear energy is anti-fragile (more disasters means saver plants). I believe we are far too cautious with building new nuclear plants. Not because I think that nuclear energy is not dangerous, but I believe global warming is a far greater risk.
  - BiteCode_dev 5y ago
    It's not an "or" proposition. Nuclear energy should not be our only source of energy for other reasons like resiliance (diversity in sources make a society more robust), power balance (you don't want one type of industry to have it all) and long term cost opportunity (some energy may prove cheaper later if we also develop them). And since we are using nuclear energy, we engage in this risk, which we should mitigate given the magnitude of it. Ignoring it is not rational. Opposing the risk of a nuclear accident to globalm warming is a false dichotomie. Like stating we don't spend money on fighting covid because cancer is more deadly, more likely, and need all the money we have.
stjohnswarts 5y ago
1. if a real effort is put in, 10 years or so 2. Solved problem. Spent fuel is not really an issue, we have solutions and areas to put it in both Europe and the USA. Only green Luddites hold it back. Storage really does not take up a lot of space. 3. Next to none if the right type of fuel stock and reactor is chosen. Obviously security comes in, but that is also a solved issue 4. Lots of modern designs literally cannot go critical, I suggest we use those, instead of old designs just because they're "a known known". 5. don't build reactors that can go critical near known tsunami shorlines. 6. At worst we'll surely have fusion by the end of the century and can then retire the nuclear plants. Solar and wind without a 100x improvement in battery storage tech do not make sense right now as the sole producer of energy like a lot of unrealistic "environmental" groups claim.
- effie 5y ago
  This was going well until point 6. Fusion isn't anywhere near practical in 2021, it requires lots of investment and research to do even a first prototype. And it is a high tech marvel that won't be cheap to operate. So the funding for it may eventually dry out in favour of boring tech fission plants.
  - stjohnswarts 5y ago
    I said by the end of the century, not 2021. Fission plants are the answer until fusion becomes practical.
    - effie 5y ago
      OK point taken. But predicting things 80 years into future is extremely difficult. It is by no means certain we will get there in under 80 years.

by eecc 5y ago

funklute 5y ago

None of those questions are new, nor show stoppers for existing plants. Why do you think the existing procedures may not be satisfactory? (I'm assuming you think so based on the way you ask the question) EDIT: to be clear, I'm not asking this as a backhanded question. I'm genuinely curious why this is not seen as a "solved problem", at least in a country with relatively strong government institutions

eecc 5y ago
Well, the way previous generations fizzled suggests these problems aren’t that solved after all. Just 1 long term waste storage has ever been built in the world, plant productivity has always been relatively low (initial manufacturing delays, refueling, minor accidents, refurbishments), many anti-proliferation techniques just over-produce rad-waste. Oh, and if we were to buildout nuclear globally how long would the ore reserves last?
- R0b0t1 5y ago
  It fizzled due to FUD. Existing plants work and are defensible. The waste can be stored safely. In emerging economies new designs can be used, but they'll probably have to be trialed in a developed economy. You could also pursue economic policy that has developing economies fund the research instead of letting them expect handouts.
  - wolverine876 5y ago
    > It fizzled due to FUD. You're saying there were no actual, serious problems with nuclear plants? > Existing plants work and are defensible. That's survivorship bias to a degree: Te plants that work and are defensible are the plants you see. It's also a bias of sunk costs: The surviving plants could have been way over-budget and late, but it's still worth operating them.
    - vkou 5y ago
      > You're saying there were no actual, serious problems with nuclear plants? Compared to other forms of energy generation, measured in illnesses, injuries, maimings, and deaths, past and plausibly attributed to the future, per KWH? Not really, no.
      - wolverine876 5y ago
        I tire of the 'say something bold and prove me wrong' rhetoric, when people know exactly what's wrong with what they are saying. It doesn't contribute to anyone's understanding, and wastes my time. Hope the rest of your day goes well.
        vkou 5y ago
        The realization that industrial processes are dangerous, that power generation is an industrial process, and therefore dangerous, and that the only meaningful way to measure the danger of an industrial process is by comparing it to that of another industrial process should contribute to the understanding of some. Is nuclear power generation dangerous? Yes. Is all power generation dangerous? Yes. How dangerous is nuclear power generation compared to alternatives? Not very. It's pretty accurate to say that nuclear fizzled due to FUD. The conversation ended after the answer to the first question was 'yes'.
        johncolanduoni 5y ago
        I’d appreciate if you could clarify what’s wrong. Even if both you and your interlocutor understand it, the point has unfortunately gone over my head (and possibly the same for others reading).
        consumer451 5y ago
        Not OP, but one problem that they mentioned which is "wrong" from an economic point of view is that afaik, there is no way to calculate the total cost of ownership of a nuclear plant. This is due to that fact that there are no viable plans for long term nuclear storage to calculate the cost of. Is this not "wrong" in a very material way?
- blendergeek 5y ago
  > Oh, and if we were to buildout nuclear globally how long would the ore reserves last? If we fully burn all available nuclear fuel, it will last about 5 billion years. [0] [0] https://web.archive.org/web/20130114062518/http://sustainablenuclear.org/PADs/pad11983cohen.pdf https://web.archive.org/web/20130114062518/http://sustainabl...
  - eecc 5y ago
    Ah that’s breeders, it’s a different game. They’re technically more challenging (the French spent billions on their plants which didn't quite deliver) and have a significant nuclear weapons proliferation risk. Somewhere I read (sorry for the lack of sources) that with single-pass fuel use, known reserves would only last a couple decades, a century at best.
    - effie 5y ago
      > have a significant nuclear weapons proliferation risk. Why. What risk of proliferation is there in France, UK or U.S.? These states already have nuclear weapons.
      - onecommentman 5y ago
        A global buildout of breeders is the issue. The rich countries telling the poor countries they can’t have nice things because of “our” security concerns. Big talking point in the 1960s. Tom Lehrer even wrote a cute song about nuclear proliferation in 1964, “Who’s Next?”. If you get any expansive policy and process wrong, the negative global consequences are dramatic and long-lasting. So, first, do no harm.

user_7832 5y ago

I can try to answer your questions. (Disclaimer, I'm a masters student studying systems with a focus on energy systems. Obviously not an expert, and am somewhat biased pro-nuclear.) 1. Net online time for nuclear isn't particularly bad, especially when you consider that other alternatives too go down. [1] Of course you'll need some extra capacity/more plants, but that was anyway the case. 2. I feel this is probably the strongest point that can be held against nuclear. Short-term fuel management is not an issue/already figured out, and climate change is a much quicker risk in the next 50 years, so I'd argue it's still better to go 0-carbon instead of finding a perfect solution right now. 3. I'm not sure if you're referring to proliferation of the fuel or technologies, but both are reasonably well-developed fields that France should not have major problems. 4. Similar to point one - nuclear accidents vs risks/deaths from coal is like comparing flight safety with cars. Sure, airplanes feel unsafe but are statistically MUCH safer than cars. Chernobyl and Fukushima were both avoidable (though that can admitably be said for a lot of accidents). Deaths from pollution itself are in the millions instead. [2] 1. https://www.energy.gov/ne/articles/nuclear-power-most-reliable-energy-source-and-its-not-even-close https://www.energy.gov/ne/articles/nuclear-power-most-reliab... 2. https://ourworldindata.org/safest-sources-of-energy https://ourworldindata.org/safest-sources-of-energy

majou 5y ago
Proliferation in the context of nuclear is the risk of terrorists or states intercepting fuel that can be refined to weapon-grade. Some reactors don't have this risk, but I'm not read on it.
- ineedasername 5y ago
  Decades with hundred of nuclear power plants in the world have not seen them be a significant source of fissionable material for terrorists or new nations developing nuclear weapons. See Iran, a nation that has devoted significant resources to such an endeavor, as a case in point. Spent fuel from nuclear power plants-- probably the more vulnerable point in the supply chain-- is nonetheless difficult to the point of extreme expense & impractical to refine to weapons grade. You would need such large quantities that it would be extremely difficult to steal enough without notice: Someone is going to notice the 200,000 lb cask leaving a storage facility. Then the refinement process is difficult, requiring immense sums of money to built the significant infrastructure required for refinement. North Korea, the newest nuclear power, got there with significant help from the Soviets extending back in the 60's and it still took them decades to get there. This is all on top of the fact that any modern plant designs use feedstock fuel that is even harder to refine into anything weapons grade, and is much more efficient to the point that spend fuel refinement difficulties dwarfs the above roadblocks for fuel from older designs. Dirty bombs are more problematic, but also significantly less destructive, and suffer from many of the same logistical hurdles, notably that the material most useful for a dirty bomb is also material that requires massively robust precautions to ensure the thieves don't kill themselves with radiation exposure long before any chance of making use of it. Less useful material that requires fewer precautions is not practical for dirty bombs without significant refinement capacity. All of this at a time when real measurable deaths from fossil fuel powerplants, their pollution, and their industrial accidents, are themselves more dangerous, right now, than theoretical & difficult to achieve usages of fuel from new nuclear power plants.

axlee 5y ago

France has been running on 75%+ nuclear power mix for the past 50 years and is doing better energy/emissions-wise than almost every other country in the world. Your questions have already been answered, it seems. They seem to have bet on the right horse, and went full steam ahead with it (no pun intended). And now they are supplying all their neighbours with surplus clean energy.

stjohnswarts 5y ago
I always point at this when my American "environmental" friends yell at me as a proponent of a Manhattan style project in nuclear tech here in the USA as the solution to climate change.
- throw0101a 5y ago
  See also the province of Ontario ("Supply" tab): * https://www.ieso.ca/power-data https://www.ieso.ca/power-data

monocasa 5y ago

France has significantly less spent fuel to deal with since they allow civilian energy production to reprocess spent fuel back into usable fuel.

eecc 5y ago
True, but breeder technology has a lot more potential for weaponry proliferation (part of the reason France is so much invested in nuclear is precisely because of that.) And it’s not as easy as recycling empty glass bottles… the French struggled to keep their breeders online and keep them economical (but then the military we’re still happy so…)

godelski 5y ago

> 1. What will the net online time be? Hard to say tbh. But these reactors probably aren't offline as much as you think. They shut down for 1 month every 18-24 months for refueling. > 2. Spent fuel? France is the world leader in this regard. Remember that 17% of France's entire power comes from _recycled_ nuclear. But if you want to see what their entire nuclear waste. This is _decades_ worth, and I'm betting much smaller than you expected.[0] (coal is doing this on a a daily or weekly basis). Just for fun, let's look at Russia's too.[1] We're literally just talking a warehouse. People vastly overestimate the waste and what to do with it. It is fine where it is for hundreds of years. The only "problem" that we have with "long term storage" is how to store it somewhere where if somehow all knowledge was lost that future humans with no radiation detecting equipment could accidentally release waste (quite a high bar, and not one we're concerned with other long lasting waste like lead or heavy metals). We have a few hundred years to figure that out. > 3. Proliferation risk? None? It is France. They already have nuclear weapons. But while we're talking about it, Megatons to Megawatts[2] has been the best deproliferation project in history, reducing the number of nuclear warheads by over 20,000. > 4. Accident mitigation? Very low. This is also over estimated. We have a very early reactor which no other country besides Russia built because it had the ability to explode. And we have another event where we didn't know earthquakes could happen of that size until basically right before said earthquake happened. These are major disasters, but the two should not be conflated. Even including these, they are far less environmentally damaging than the fossil fuels we've been using. The major problem with nuclear is that disasters are both temporally and spatially localized. There's advantages and disadvantages to this in terms of dealing with the consequences. On one hand, it is a lot to clean up. On the other hand the country that created the disaster is the one that suffers the most (as opposed to what we're seeing with oil spills and the entire climate crisis, which is not temporally localized and thus the danger is not weighted properly). [0] https://twitter.com/Orano_usa/status/1182662569619795968 https://twitter.com/Orano_usa/status/1182662569619795968 [1] https://www.youtube.com/watch?v=_5uN0bZBOic&t=105s https://www.youtube.com/watch?v=_5uN0bZBOic&t=105s [2] https://en.wikipedia.org/wiki/Megatons_to_Megawatts_Program https://en.wikipedia.org/wiki/Megatons_to_Megawatts_Program

wolverine876 5y ago
>> 3. Proliferation risk? > None? It is France. They already have nuclear weapons. But while we're talking about it, Megatons to Megawatts[2] has been the best deproliferation project in history, reducing the number of nuclear warheads by over 20,000. More nuclear trained personnel, designs, materials, and plants mean more opportunities for someone to acquire technology or materials.

Manuel_D 5y ago

1. What will the net online time be? (Lots of these plants go in maintenance for long stretches of time) The term you're referring to is capacity factor. Nuclear power typically has the highest capacity factor of any energy source. [1] [2] For reference, nuclear is 92%, while wind is 35% and photovoltaic solar at 25%. > 2. Spent fuel? It can be reprocessed, reclaiming over 90% of fuel. Even without reprocessing, nuclear fuel's energy density is such that a tiny amount of waste is produced per unit of energy. For comparison, the sum total of all of the USA's nuclear electricity production occupies a volume the footprint of a football field, and 10 yards high. [3] > 3. Proliferation risk? Nuclear fuel is refined to about ~20% fissile material. Nuclear weapons typically need over 80% or 90%. Countries would need to build their own enrichment facilities to bring nuclear fuel to weapons grade uranium, and then further refine that to plutonium. If they had such facilities they'd be able to refine natural uranium to weapons grade anyway. > 4. Accident mitigation? First of all, even if you include Chernobyl nuclear power (which didn't even have secondary storage) has the lowest fatalities per unit of energy produced [4]. People often neglect the fact that fossil fuels kill millions each year due to air pollution. Renewables like hydroelectricity have had accidents far more devastating that nuclear power [5]. Nuclear plants are expensive because a lot of effort is made to make them safe, and to contain a potential failure. People often forget that the USA had a reactor meltdown analogous to Chernobyl during the Three Mile Island incident. Except nobody died and there was no widespread contamination because the reactor had a big concrete condom over it, unlike Chernobyl. 1. https://www.statista.com/statistics/183680/us-average-capacity-factors-by-selected-energy-source-since-1998/ https://www.statista.com/statistics/183680/us-average-capaci... 2. https://en.wikipedia.org/wiki/Capacity_factor#Worldwide https://en.wikipedia.org/wiki/Capacity_factor#Worldwide 3. https://www.energy.gov/ne/articles/5-fast-facts-about-spent-nuclear-fuel https://www.energy.gov/ne/articles/5-fast-facts-about-spent-... 4. https://www.statista.com/statistics/494425/death-rate-worldwide-by-energy-source/ https://www.statista.com/statistics/494425/death-rate-worldw... 5. https://en.wikipedia.org/wiki/1975_Banqiao_Dam_failure https://en.wikipedia.org/wiki/1975_Banqiao_Dam_failure

wolverine876 5y ago
> Nuclear fuel is refined to about ~20% fissile material. Nuclear weapons typically need over 80% or 90%. Countries would need to build their own enrichment facilities to bring nuclear fuel to weapons grade uranium, and then further refine that to plutonium. If they had such facilities they'd be able to refine natural uranium to weapons grade anyway. I've wondered about that. On one hand, the reasoning above makes sense. On the other, people who know far more than I do say there is proliferation risk. I suspect there is something I don't understand.

BiteCode_dev 5y ago

1 - During my study, I visited a nuclear plant. They explained to us the plant is designed around 4 quadrants, each one capable of turning on and off independently of each other. So when one needs maintenance, you just put this one offline, and the others keep running. This way the reactor is never totally shut off, as I understand that starting it from scratch is an expensive operation. 2 - For the spent fuel, France has plenty of strategically maintained relationships in what used to be West African colonies with uranium mines. Why do you think we sent the army during the Mali war ? We cultivate those alliances because they bring a lot on the table, from resources to routes and bases. Nuclear is doubly interesting for us, because we can source it even if Russia or China decide to tell us to go to hell. In case of a conflict, this is priceless. 3 - I don't know anything about proliferation, so can't answer this one. 4 - Accident mitigation is the big problem, IMO. I've seen how they operate inside, and let's just say I'm glad the people that designed the thing were very, very, _very_ good at their job. Because the ones maintaining it have a very relaxed attitude. And the plants are pushed to produce way past their initial expected life span. But I insist, I'm amazed at how good engineers of the 70' were. Those plants are old tech, but they are incredible. However, even if the probability of an accident is low (there are triple safety mechanisms everywhere), the severity of a potential accident is such that I consider nuclear disasters a huge risk that we don't take seriously enough. What's more, it nourishes the growing anti-nuclear sentiment, so we should really get our act together.

enaaem 5y ago
The risks of nuclear energy is far more favourable than global warming. Global warming effects are global, non-linear and there are still many unknowns, which makes it more risky. Nuclear risks are local and the harm is well known. Also nuclear energy is anti-fragile (more disasters means saver plants). I believe we are far too cautious with building new nuclear plants. Not because I think that nuclear energy is not dangerous, but I believe global warming is a far greater risk.
- BiteCode_dev 5y ago
  It's not an "or" proposition. Nuclear energy should not be our only source of energy for other reasons like resiliance (diversity in sources make a society more robust), power balance (you don't want one type of industry to have it all) and long term cost opportunity (some energy may prove cheaper later if we also develop them). And since we are using nuclear energy, we engage in this risk, which we should mitigate given the magnitude of it. Ignoring it is not rational. Opposing the risk of a nuclear accident to globalm warming is a false dichotomie. Like stating we don't spend money on fighting covid because cancer is more deadly, more likely, and need all the money we have.

stjohnswarts 5y ago

1. if a real effort is put in, 10 years or so 2. Solved problem. Spent fuel is not really an issue, we have solutions and areas to put it in both Europe and the USA. Only green Luddites hold it back. Storage really does not take up a lot of space. 3. Next to none if the right type of fuel stock and reactor is chosen. Obviously security comes in, but that is also a solved issue 4. Lots of modern designs literally cannot go critical, I suggest we use those, instead of old designs just because they're "a known known". 5. don't build reactors that can go critical near known tsunami shorlines. 6. At worst we'll surely have fusion by the end of the century and can then retire the nuclear plants. Solar and wind without a 100x improvement in battery storage tech do not make sense right now as the sole producer of energy like a lot of unrealistic "environmental" groups claim.

effie 5y ago
This was going well until point 6. Fusion isn't anywhere near practical in 2021, it requires lots of investment and research to do even a first prototype. And it is a high tech marvel that won't be cheap to operate. So the funding for it may eventually dry out in favour of boring tech fission plants.
- stjohnswarts 5y ago
  I said by the end of the century, not 2021. Fission plants are the answer until fusion becomes practical.
  - effie 5y ago
    OK point taken. But predicting things 80 years into future is extremely difficult. It is by no means certain we will get there in under 80 years.