10 ms·

Or just use that money for solar panels and batteries and not build a combination power plant / doomsday weapon.

by w0mbat 7y ago

acidburnNSA 7y ago
MIT studies suggest that deeply decarbonizing is actually cheaper when you do some nuclear alongside your variable renewables + storage [1]. The cost of filling those seasonal solar gaps and 10-day wind gaps gets pretty large without nukes. [1] https://energy.mit.edu/research/future-nuclear-energy-carbon-constrained-world/ https://energy.mit.edu/research/future-nuclear-energy-carbon...
- pfdietz 7y ago
  Studies that purport to show that nuclear has a place due to inability of renewables to fill those gaps are usually assuming renewables + short term storage cannot fill those gaps. But renewables + short term storage + hydrogen can, and probably more cheaply than a system with nuclear reactors.
  - AnthonyMouse 7y ago
    What's hydrogen supposed to add? It's just a type of storage, and probably not even the cheapest one.
    - pfdietz 7y ago
      Hydrogen has low capital cost. The capital cost/energy of storing hydrogen underground will be much less than the cost of storing that energy in a battery. If you have a storage scenario where the energy is stored for very long times, there will be few cycles of that system over its economic lifespan, so minimizing capital cost (even if that means much lower round trip efficiency) is very important. One would still use more efficient short term storage (and over-installation of renewables sources) for diurnal load leveling. Hydrogen can also be turned back to electrical power (at lousy efficiency) with cheap hardware. In particular, simple cycle gas turbine power plants with efficiency of 40% cost maybe $400/kW. Compare this to $8-10K/kW for a new nuclear power plant.
      - AnthonyMouse 7y ago
        > In particular, simple cycle gas turbine power plants with efficiency of 40% cost maybe $400/kW. Compare this to $8-10K/kW for a new nuclear power plant. The problem being that it only operates ~2% of the time compared to ~100%, and has a shorter operating lifetime in practice, and that isn't counting the cost of storing the hydrogen nor the energy cost to produce it.
        pfdietz 7y ago
        Yes, the power will be expensive during that 2%. But it will not contribute all that much to the total cost of operating the grid. In particular, it would be cheaper than forcing the consumers to pay for nuclear the other 98% of the time, just so it would be available during that 2%.
        AnthonyMouse 7y ago
        If it's dozens of times more expensive during that 2% because it has to recover 100% of its cost in 2% of the time then it does contribute quite a bit to the total cost of operating the grid, whereas nuclear only has to make up the difference in that time between the market price the rest of the time and its overall average cost. Storage also has the further disadvantage that you have to over-spec it. It has to be built for the highest capacity you might need and the longest duration, which you don't know ahead of time. If you build less than you need you're in big trouble, but if you build more, you pay for it and get nothing.
        pfdietz 7y ago
        Simple cycle gas turbines are 20 times cheaper than nuclear power plants of equal power output. So, no, your argument doesn't hold up when the actual numbers are examined.
        AnthonyMouse 7y ago
        Being 20 times cheaper while producing 2% of the kWh because they're turned off 98% of the time makes them 250% more expensive per kWh. And that's comparing the the capital cost for the entire nuclear plant to only the turbine, not including the capital required for the hydrogen storage, or the equipment to produce the hydrogen, or the energy cost of the original generation (with large conversion losses). Or, again, the deadweight losses from the safety margin you need for surplus capacity that you might but probably won't ever use, which could double the cost or more on top of everything else. Whereas if you spec additional nuclear it means you're generating that much more useful electricity 100% of the time. Meanwhile that kind of storage will have more difficulty finding investors, because if it turns out that some cheaper or better alternative comes along, an investment in nuclear might have to average generating power below levelized cost, but at least you recover most of the capital. Putting in $100 in capital only to have the net present value fall to $80 sucks, but not nearly as much as putting in $100 in capital for a complete write off because you were expecting to be selling to the grid 2% of the time when it turns out to be 0% between demand based pricing and better than expected competing storage technologies. Which means higher capital costs (meaning interest rates) that reduce relative competitiveness even further.
- w0mbat 7y ago
  Nuclear is never actually cheap though. In practise it costs a fortune to build, a fortune to run, a fortune to dismantle, and then you have to pay to store the waste forever. Even that assessment is charitably assuming that there are no massively expensive accidents along the way.
paulsutter 7y ago
Nuclear is a great compliment to photovoltaic. One of the reasons Japan was able to go large on PV (and cause prices to come down for the rest of us) was their huge pumped water infrastructure that had been built for nuclear. One problem with nuclear was all the excess power created at night, so they would pump water uphill at night and then run it down to generate power at the daytime peaks. Of course with PV the timing was reversed but the need similar. If they hadn’t decommissioned their nuclear plants the combination would have been even better.
- pfdietz 7y ago
  Nuclear is not a great complement to PV, if the PV is cheap. Cheap PV expands until there is no residual baseload demand left. At that point, nuclear power plants cannot maintain high capacity factor and their economics go all to hell.
  - AnthonyMouse 7y ago
    Nuclear has effectively zero unit cost, it's all fixed cost. Once you build the reactor, you generate at full capacity all day and night and take whatever the market rate is. That means you get paid less during the day when solar is the cheapest provider, but you still match its price and supply your full generation capacity even then, because you can, because anything is more than nothing and the incremental generation cost is effectively zero. Then you make more at night when solar requires storage, and even more still whenever the day was overcast and energy prices had to rise high enough to suppress demand enough that the depleted storage isn't fully exhausted before sunrise. The capacity factor is always 100%, it's the price you get at any given time that varies. But price variability in itself is no problem either, as long as the average price is above average cost. And that average includes not only times that it rains for multiple days in a row, but also winter, and that with consideration of people also needing to switch from oil and gas to electric heat.
    - Marazan 7y ago
      No

Or just use that money for solar panels and batteries and not build a combination power plant / doomsday weapon.

by w0mbat 7y ago

Or just use that money for solar panels and batteries and not build a combination power plant / doomsday weapon.

MIT studies suggest that deeply decarbonizing is actually cheaper when you do some nuclear alongside your variable renewables + storage [1]. The cost of filling those seasonal solar gaps and 10-day wind gaps gets pretty large without nukes. [1] https://energy.mit.edu/research/future-nuclear-energy-carbon-constrained-world/ https://energy.mit.edu/research/future-nuclear-energy-carbon...

pfdietz 7y ago
Studies that purport to show that nuclear has a place due to inability of renewables to fill those gaps are usually assuming renewables + short term storage cannot fill those gaps. But renewables + short term storage + hydrogen can, and probably more cheaply than a system with nuclear reactors.
- AnthonyMouse 7y ago
  What's hydrogen supposed to add? It's just a type of storage, and probably not even the cheapest one.
  - pfdietz 7y ago
    Hydrogen has low capital cost. The capital cost/energy of storing hydrogen underground will be much less than the cost of storing that energy in a battery. If you have a storage scenario where the energy is stored for very long times, there will be few cycles of that system over its economic lifespan, so minimizing capital cost (even if that means much lower round trip efficiency) is very important. One would still use more efficient short term storage (and over-installation of renewables sources) for diurnal load leveling. Hydrogen can also be turned back to electrical power (at lousy efficiency) with cheap hardware. In particular, simple cycle gas turbine power plants with efficiency of 40% cost maybe $400/kW. Compare this to $8-10K/kW for a new nuclear power plant.
    - AnthonyMouse 7y ago
      > In particular, simple cycle gas turbine power plants with efficiency of 40% cost maybe $400/kW. Compare this to $8-10K/kW for a new nuclear power plant. The problem being that it only operates ~2% of the time compared to ~100%, and has a shorter operating lifetime in practice, and that isn't counting the cost of storing the hydrogen nor the energy cost to produce it.
      - pfdietz 7y ago
        Yes, the power will be expensive during that 2%. But it will not contribute all that much to the total cost of operating the grid. In particular, it would be cheaper than forcing the consumers to pay for nuclear the other 98% of the time, just so it would be available during that 2%.
        AnthonyMouse 7y ago
        If it's dozens of times more expensive during that 2% because it has to recover 100% of its cost in 2% of the time then it does contribute quite a bit to the total cost of operating the grid, whereas nuclear only has to make up the difference in that time between the market price the rest of the time and its overall average cost. Storage also has the further disadvantage that you have to over-spec it. It has to be built for the highest capacity you might need and the longest duration, which you don't know ahead of time. If you build less than you need you're in big trouble, but if you build more, you pay for it and get nothing.
        pfdietz 7y ago
        Simple cycle gas turbines are 20 times cheaper than nuclear power plants of equal power output. So, no, your argument doesn't hold up when the actual numbers are examined.
        AnthonyMouse 7y ago
        Being 20 times cheaper while producing 2% of the kWh because they're turned off 98% of the time makes them 250% more expensive per kWh. And that's comparing the the capital cost for the entire nuclear plant to only the turbine, not including the capital required for the hydrogen storage, or the equipment to produce the hydrogen, or the energy cost of the original generation (with large conversion losses). Or, again, the deadweight losses from the safety margin you need for surplus capacity that you might but probably won't ever use, which could double the cost or more on top of everything else. Whereas if you spec additional nuclear it means you're generating that much more useful electricity 100% of the time. Meanwhile that kind of storage will have more difficulty finding investors, because if it turns out that some cheaper or better alternative comes along, an investment in nuclear might have to average generating power below levelized cost, but at least you recover most of the capital. Putting in $100 in capital only to have the net present value fall to $80 sucks, but not nearly as much as putting in $100 in capital for a complete write off because you were expecting to be selling to the grid 2% of the time when it turns out to be 0% between demand based pricing and better than expected competing storage technologies. Which means higher capital costs (meaning interest rates) that reduce relative competitiveness even further.
w0mbat 7y ago
Nuclear is never actually cheap though. In practise it costs a fortune to build, a fortune to run, a fortune to dismantle, and then you have to pay to store the waste forever. Even that assessment is charitably assuming that there are no massively expensive accidents along the way.

paulsutter 7y ago

Nuclear is a great compliment to photovoltaic. One of the reasons Japan was able to go large on PV (and cause prices to come down for the rest of us) was their huge pumped water infrastructure that had been built for nuclear. One problem with nuclear was all the excess power created at night, so they would pump water uphill at night and then run it down to generate power at the daytime peaks. Of course with PV the timing was reversed but the need similar. If they hadn’t decommissioned their nuclear plants the combination would have been even better.

pfdietz 7y ago
Nuclear is not a great complement to PV, if the PV is cheap. Cheap PV expands until there is no residual baseload demand left. At that point, nuclear power plants cannot maintain high capacity factor and their economics go all to hell.
- AnthonyMouse 7y ago
  Nuclear has effectively zero unit cost, it's all fixed cost. Once you build the reactor, you generate at full capacity all day and night and take whatever the market rate is. That means you get paid less during the day when solar is the cheapest provider, but you still match its price and supply your full generation capacity even then, because you can, because anything is more than nothing and the incremental generation cost is effectively zero. Then you make more at night when solar requires storage, and even more still whenever the day was overcast and energy prices had to rise high enough to suppress demand enough that the depleted storage isn't fully exhausted before sunrise. The capacity factor is always 100%, it's the price you get at any given time that varies. But price variability in itself is no problem either, as long as the average price is above average cost. And that average includes not only times that it rains for multiple days in a row, but also winter, and that with consideration of people also needing to switch from oil and gas to electric heat.
  - Marazan 7y ago
    No