4 ms·

See also, peak uranium : https://en.m.wikipedia.org/wiki/Peak_uranium https://en.m.wikipedia.org/wiki/Peak_uranium 2017 known supply is enough for 130 years at

See also, peak uranium : https://en.m.wikipedia.org/wiki/Peak_uranium https://en.m.wikipedia.org/wiki/Peak_uranium 2017 known supply is enough for 130 years at current usage (supplying about 10% of global energy). Each doubling of production halves the peak timeline. Basically no one expects discovery to outpace usage. So, at best, nuclear is a stop gap and part of a different long term solution. Which could be fine! But the extremely low LCOE and fast build time for modern renewables suggests that nuclear is simply losing the race for relevance.

korantu 5y ago
Fuel is very small part in cost of nuclear generation; As fuel price start increasing, more sources become viable, including sea water. There is practically unlimited supply once it happens, and this is before accounting for reprocessing. (and reprocessing happens in France, for example)
- sdenton4 5y ago
  Right, but the fuel cost goes up over time as extraction gets harder (eventually requiring entire new types of facilities, which themselves take a decade to build), even as wind and solar continue their exponentially decreasing LCOE cost curve. The exponentially decreasing cost curve is the part that I think people haven't actually internalized. The arguments on the pro-nuclear side are pretty much the same as they were ten years ago. (right down to 'we'll have thorium in ten years!') But things are very different now: It's like arguing for large scale investment in punch-card sorting machines circe 1960. Yes, the punch-card sorting machines can be used to manage all your bank data, but the digital processing are getting exponentially better with time and have been actually better for a couple years. But the proponents of punch card sorting machines haven't internalized the message yet.
  - cnlevy 5y ago
    > Right, but the fuel cost goes up over time as extraction gets harder Uranium demand is declining, there has been almost no Uranium prosection in the last decades; Therefore it's no wonder reserves are diminishing. If demand picks up, prospecting will renew, and a lot more uranium will be discovered. This is not accounting for thorium reserves, which have never been seriously prospected.
  - vkou 5y ago
    > even as wind and solar continue their exponentially decreasing LCOE cost curve. What you think is an exponential curve is actually the left side of a sigmoid.
    - sdenton4 5y ago
      Your meme pertains to exponential /growth/, not exponential /decline/. Exponential growth in a population hits a limit as a population saturates, causing the sigmoid shape. Exponential decline hits a constant asymptote and bottoms out. For populations, that asymptote tends to be zero. For cost curves, as in the solar panel case, it will be something more like capital cost of production divided by panel lifetime, which can be a very small number indeed.
bbojan 5y ago
Current reactors (light and heavy water reactors) all use solid fuel, which is very inefficient due to use of once-through fuel cycle. Because xenon is the most common fission product, and it's a gas, the reaction must be stopped before all fuel is used, as otherwise the solid fuel pellets would crack. If you assume 3% enriched uranium (U-235) and 97% depleted uranium (U-238) (a typical fuel load), the fuel pellets are unusable after about 1/3 of enriched uranium is spent. So the fuel is removed and "thrown away" while it still has 2% U-235 in it. Switching to liquid fuel reactors assuming no other changes would immediately increase supply 3 times (because xenon simply bubbles out). Switching to liquid fuel breeder reactors ~ 100 times. Switching to breeders based on thorium - around 1000 to 10000 times. Peak uranium is only a problem because we're using a very inefficient nuclear reactor technology - water reactors. Why? Because they were chosen by the military and the technology/know-how was already there. Efficiency was really low on the military's list of priorities.
- acidburnNSA 5y ago
  Switching to solid fuel uranium breeders + fluid fuel thorium breeders gets you to around 4 billion years.
- pfdietz 5y ago
  I thought fuel pellet cracking was already a tolerated thing. Pressure builds up in fuel rods due to escaped xenon and krypton.
acidburnNSA 5y ago
There's more to it than that. The long-term plan for nuclear fission always has been and remains to use breeder reactors after we have ~1000 GW-scale non-breeder reactors in place. Because they can utilize the majority isotope of uranium (U-238) and Thorium rather than just the small natural amount of fissile U-235, breeders enable us to make 100% of the world's primary energy for about 4 billion years (e.g. roughly until the sun burns out) [1]. [1] https://whatisnuclear.com/blog/2020-10-28-nuclear-energy-is-longterm-sustainable.html https://whatisnuclear.com/blog/2020-10-28-nuclear-energy-is-... The same point was made in the Hot Air book as well [2] [2] https://www.withouthotair.com/c24/page_162.shtml https://www.withouthotair.com/c24/page_162.shtml Since this is roughly the remaining lifetime of the Sun, there's a very strong argument to consider nuclear fission breeder reactors just as renewable as the solar-derived energies (wind, solar, hydro, biofuel)
- pfdietz 5y ago
  Which means that nuclear proponents should use the cost of breeder reactors with reprocessing, not burner reactors with a once-through fuel cycle, when calculating the cost of nuclear energy. This will likely increase the cost of energy from nuclear.
  - acidburnNSA 5y ago
    I don't really know about that. After we have 1000 GW scale lwrs the prices of reprocessing might be different than today's prices.
    - pfdietz 5y ago
      And when we scale out wind and solar they will be cheaper too. Given the historical experience curves, this argument will favor those, not nuclear.
  - KennyBlanken 5y ago
    If we forced them to be honest we'd also force them to account for the huge carbon sink the plant represents until it has generated enough power to offset its construction footprint. We need solutions that pay back as fast as possible, not stuff that will go neutral in 20 years.
pfdietz 5y ago
> (supplying about 10% of global energy). Current nuclear supplies 10% of global ELECTRICAL energy, not total energy. If you scale burner reactors to supply the 18 TW of primary energy demand the world uses, projected cheap uranium runs out rather quickly.

korantu 5y ago

Fuel is very small part in cost of nuclear generation; As fuel price start increasing, more sources become viable, including sea water. There is practically unlimited supply once it happens, and this is before accounting for reprocessing. (and reprocessing happens in France, for example)

sdenton4 5y ago
Right, but the fuel cost goes up over time as extraction gets harder (eventually requiring entire new types of facilities, which themselves take a decade to build), even as wind and solar continue their exponentially decreasing LCOE cost curve. The exponentially decreasing cost curve is the part that I think people haven't actually internalized. The arguments on the pro-nuclear side are pretty much the same as they were ten years ago. (right down to 'we'll have thorium in ten years!') But things are very different now: It's like arguing for large scale investment in punch-card sorting machines circe 1960. Yes, the punch-card sorting machines can be used to manage all your bank data, but the digital processing are getting exponentially better with time and have been actually better for a couple years. But the proponents of punch card sorting machines haven't internalized the message yet.
- cnlevy 5y ago
  > Right, but the fuel cost goes up over time as extraction gets harder Uranium demand is declining, there has been almost no Uranium prosection in the last decades; Therefore it's no wonder reserves are diminishing. If demand picks up, prospecting will renew, and a lot more uranium will be discovered. This is not accounting for thorium reserves, which have never been seriously prospected.
- vkou 5y ago
  > even as wind and solar continue their exponentially decreasing LCOE cost curve. What you think is an exponential curve is actually the left side of a sigmoid.
  - sdenton4 5y ago
    Your meme pertains to exponential /growth/, not exponential /decline/. Exponential growth in a population hits a limit as a population saturates, causing the sigmoid shape. Exponential decline hits a constant asymptote and bottoms out. For populations, that asymptote tends to be zero. For cost curves, as in the solar panel case, it will be something more like capital cost of production divided by panel lifetime, which can be a very small number indeed.

bbojan 5y ago

Current reactors (light and heavy water reactors) all use solid fuel, which is very inefficient due to use of once-through fuel cycle. Because xenon is the most common fission product, and it's a gas, the reaction must be stopped before all fuel is used, as otherwise the solid fuel pellets would crack. If you assume 3% enriched uranium (U-235) and 97% depleted uranium (U-238) (a typical fuel load), the fuel pellets are unusable after about 1/3 of enriched uranium is spent. So the fuel is removed and "thrown away" while it still has 2% U-235 in it. Switching to liquid fuel reactors assuming no other changes would immediately increase supply 3 times (because xenon simply bubbles out). Switching to liquid fuel breeder reactors ~ 100 times. Switching to breeders based on thorium - around 1000 to 10000 times. Peak uranium is only a problem because we're using a very inefficient nuclear reactor technology - water reactors. Why? Because they were chosen by the military and the technology/know-how was already there. Efficiency was really low on the military's list of priorities.

acidburnNSA 5y ago
Switching to solid fuel uranium breeders + fluid fuel thorium breeders gets you to around 4 billion years.
pfdietz 5y ago
I thought fuel pellet cracking was already a tolerated thing. Pressure builds up in fuel rods due to escaped xenon and krypton.

acidburnNSA 5y ago

There's more to it than that. The long-term plan for nuclear fission always has been and remains to use breeder reactors after we have ~1000 GW-scale non-breeder reactors in place. Because they can utilize the majority isotope of uranium (U-238) and Thorium rather than just the small natural amount of fissile U-235, breeders enable us to make 100% of the world's primary energy for about 4 billion years (e.g. roughly until the sun burns out) [1]. [1] https://whatisnuclear.com/blog/2020-10-28-nuclear-energy-is-longterm-sustainable.html https://whatisnuclear.com/blog/2020-10-28-nuclear-energy-is-... The same point was made in the Hot Air book as well [2] [2] https://www.withouthotair.com/c24/page_162.shtml https://www.withouthotair.com/c24/page_162.shtml Since this is roughly the remaining lifetime of the Sun, there's a very strong argument to consider nuclear fission breeder reactors just as renewable as the solar-derived energies (wind, solar, hydro, biofuel)

pfdietz 5y ago
Which means that nuclear proponents should use the cost of breeder reactors with reprocessing, not burner reactors with a once-through fuel cycle, when calculating the cost of nuclear energy. This will likely increase the cost of energy from nuclear.
- acidburnNSA 5y ago
  I don't really know about that. After we have 1000 GW scale lwrs the prices of reprocessing might be different than today's prices.
  - pfdietz 5y ago
    And when we scale out wind and solar they will be cheaper too. Given the historical experience curves, this argument will favor those, not nuclear.
- KennyBlanken 5y ago
  If we forced them to be honest we'd also force them to account for the huge carbon sink the plant represents until it has generated enough power to offset its construction footprint. We need solutions that pay back as fast as possible, not stuff that will go neutral in 20 years.

pfdietz 5y ago

> (supplying about 10% of global energy). Current nuclear supplies 10% of global ELECTRICAL energy, not total energy. If you scale burner reactors to supply the 18 TW of primary energy demand the world uses, projected cheap uranium runs out rather quickly.