4 ms·

"May." I haven't seen anyone actually do that, have you? All I see are researchers ignoring nuclear and proving that an all-renewables grid is possible, not tha

"May." I haven't seen anyone actually do that, have you? All I see are researchers ignoring nuclear and proving that an all-renewables grid is possible, not that it's cheaper than a grid including nuclear. At one point MIT had a US grid simulator online and I played around with it for a while. The cheapest fossil-free combination I found was solar and nuclear. Basically enough nuclear for nighttime demand, and enough solar for extra daytime demand. Wind+solar+storage was a good bit costlier. And that was with conventional nuclear cost. We should probably find out whether, in practice, it's cheaper to mass-produce passively-safe small modular reactors in factories.

pfdietz 5y ago
Look at this website https://model.energy/ https://model.energy/ It models minimum cost combinations of renewables, batteries, and hydrogen to supply synthetic baseload given historical weather data (insolation, wind) in various places. It can also include nuclear (enable option "Dispatchable 2", which is based on EPR.) Twiddle the cost assumptions as you like to see what dominates. Passively safe small reactors are the latest in nuclear magical thinking. Yes, this time, the it-will-be-cheaper promise will be real, unlike all the other times it was a lie. At some point Charlie Brown the Nuclear Stan needs to realize Lucy is going to pull away the football again.
- DennisP 5y ago
  I'll spend some time with that, thanks! Edit: From some initial attempts, using their EPR costs does leave nuclear out entirely, in both the US and China. However, cutting the nuclear capital cost in half results in a grid that is completely nuclear. And it's not all or nothing. Reducing nuclear capital cost to 2/3 of the EPR value, the US gets a mix of sources with 63% nuclear. Whether such cost reductions are feasible, we'll see. You may be right, but I'll note that we have never actually tried mass-producing lots of small passively-safe reactors, or done more than early experiments with MSRs. I'm glad there are companies and countries giving it a shot. Edit2: Actually, even current production nuclear technology can get us there, if we follow the lead of the most effective countries. See figure 12 in this study of global nuclear cost curves: https://www.sciencedirect.com/science/article/pii/S0301421516300106 https://www.sciencedirect.com/science/article/pii/S030142151...
  - DennisP 5y ago
    Also, their default nuclear lifetime is 25 years, and we have many reactors older than that running right now. In my tests above I changed the lifetime to 60 years. Justification for that here: https://www.energy.gov/ne/articles/whats-lifespan-nuclear-reactor-much-longer-you-might-think https://www.energy.gov/ne/articles/whats-lifespan-nuclear-re... For some countries, even the original capital cost of 6000 is viable with a 60-year lifetime. Two I tried are Thailand and, ironically, Germany, both of which went 100% nuclear that way.
    - pfdietz 5y ago
      Assuming a 40 year lifetime in an environment of rapidly declining costs (for the competition) is dubious. Note that we're already seeing some nuclear plants in the US that can't compete just based on their operating costs. TMI's remaining reactor was cash flow negative for six years before it was shut down. It still worked fine, it just didn't make sense to keep running it. Plenty of other plants are cash flow positive but aren't selling their output at a price that would justify their replacement with a new NPP. One can view the strong position of gas-fired generating capacity in the US not just as a consequence of the low cost of natural gas, but also the low capital cost, which limits the downside risk of future competition. A combined cycle power plant might cost 10% or less the capital cost of a NPP, per unit power output.
      - DennisP 5y ago
        Nuclear today is competing against cheap, dispatchable natural gas. That's not relevant to a model of a carbon-free grid, where nuclear could displace the higher costs required to get dispatchable power from wind/solar. Nuclear's main cost is capital, so using an artificially low lifetime biases heavily against nuclear. The model accounts for operating costs separately. Whether other tech will make nuclear uncompetitive is what we're trying to find out with this model; if we start by assuming that, and limit nuclear lifetime accordingly, then we're making a circular argument. I did notice that fixed O&M costs are expressed as a percentage of capital cost, so if I take them at face value and halve the capital cost, to be conservative perhaps I should double the O&M from 3% to 6%, which I hadn't done before. That doesn't change the German and Thai results, since for those I only changed lifetime. But in the US, it means capital cost of 3000 still results in a grid without nuclear. But is that number correct? Not quite. Across the nuclear fleet, the average US nuclear O&M cost is $132/kWh, or 125 euros: https://www.epa.gov/sites/default/files/2019-03/documents/attachment_4-1_nuclear_power_plant_life_extension_cost_development_methodology_1.pdf https://www.epa.gov/sites/default/files/2019-03/documents/at... That's only 2.1% of 6000. If we lower capital cost without lowering O&M, we get 4.2% of 3000. That puts a small amount of nuclear back in the US market. However, they default to a discount rate of 10 for nuclear, and only 5 for wind/solar/battery. I don't see any reason to use different numbers here. Setting nuclear to 5, with the above changes, gets us back to a 100% nuclear US grid. Even if we take O&M back up to 6%, a capital cost of 3000 and discount rate of 5% means a 100% nuclear US. Comparing overall grid cost of two examples: With no nuclear (due to 10% discount), the US average grid cost is 53.7 EUR/MWh. With 100% nuclear (due to 5% discount and 3000 capital cost), the US grid cost is 48.6 EUR/MWh. In any case, this has changed my view somewhat. I'd thought that nuclear was a clear winner over storage, but it looks like nuclear's place is at least marginal in the US. We have copious wind and solar, and nuclear only lowers overall grid cost if we can manage the sort of nuclear costs they've achieved in South Korea. But in countries less favorable to wind/solar, nuclear dominates.

pfdietz 5y ago

Look at this website https://model.energy/ https://model.energy/ It models minimum cost combinations of renewables, batteries, and hydrogen to supply synthetic baseload given historical weather data (insolation, wind) in various places. It can also include nuclear (enable option "Dispatchable 2", which is based on EPR.) Twiddle the cost assumptions as you like to see what dominates. Passively safe small reactors are the latest in nuclear magical thinking. Yes, this time, the it-will-be-cheaper promise will be real, unlike all the other times it was a lie. At some point Charlie Brown the Nuclear Stan needs to realize Lucy is going to pull away the football again.

DennisP 5y ago
I'll spend some time with that, thanks! Edit: From some initial attempts, using their EPR costs does leave nuclear out entirely, in both the US and China. However, cutting the nuclear capital cost in half results in a grid that is completely nuclear. And it's not all or nothing. Reducing nuclear capital cost to 2/3 of the EPR value, the US gets a mix of sources with 63% nuclear. Whether such cost reductions are feasible, we'll see. You may be right, but I'll note that we have never actually tried mass-producing lots of small passively-safe reactors, or done more than early experiments with MSRs. I'm glad there are companies and countries giving it a shot. Edit2: Actually, even current production nuclear technology can get us there, if we follow the lead of the most effective countries. See figure 12 in this study of global nuclear cost curves: https://www.sciencedirect.com/science/article/pii/S0301421516300106 https://www.sciencedirect.com/science/article/pii/S030142151...
- DennisP 5y ago
  Also, their default nuclear lifetime is 25 years, and we have many reactors older than that running right now. In my tests above I changed the lifetime to 60 years. Justification for that here: https://www.energy.gov/ne/articles/whats-lifespan-nuclear-reactor-much-longer-you-might-think https://www.energy.gov/ne/articles/whats-lifespan-nuclear-re... For some countries, even the original capital cost of 6000 is viable with a 60-year lifetime. Two I tried are Thailand and, ironically, Germany, both of which went 100% nuclear that way.
  - pfdietz 5y ago
    Assuming a 40 year lifetime in an environment of rapidly declining costs (for the competition) is dubious. Note that we're already seeing some nuclear plants in the US that can't compete just based on their operating costs. TMI's remaining reactor was cash flow negative for six years before it was shut down. It still worked fine, it just didn't make sense to keep running it. Plenty of other plants are cash flow positive but aren't selling their output at a price that would justify their replacement with a new NPP. One can view the strong position of gas-fired generating capacity in the US not just as a consequence of the low cost of natural gas, but also the low capital cost, which limits the downside risk of future competition. A combined cycle power plant might cost 10% or less the capital cost of a NPP, per unit power output.
    - DennisP 5y ago
      Nuclear today is competing against cheap, dispatchable natural gas. That's not relevant to a model of a carbon-free grid, where nuclear could displace the higher costs required to get dispatchable power from wind/solar. Nuclear's main cost is capital, so using an artificially low lifetime biases heavily against nuclear. The model accounts for operating costs separately. Whether other tech will make nuclear uncompetitive is what we're trying to find out with this model; if we start by assuming that, and limit nuclear lifetime accordingly, then we're making a circular argument. I did notice that fixed O&M costs are expressed as a percentage of capital cost, so if I take them at face value and halve the capital cost, to be conservative perhaps I should double the O&M from 3% to 6%, which I hadn't done before. That doesn't change the German and Thai results, since for those I only changed lifetime. But in the US, it means capital cost of 3000 still results in a grid without nuclear. But is that number correct? Not quite. Across the nuclear fleet, the average US nuclear O&M cost is $132/kWh, or 125 euros: https://www.epa.gov/sites/default/files/2019-03/documents/attachment_4-1_nuclear_power_plant_life_extension_cost_development_methodology_1.pdf https://www.epa.gov/sites/default/files/2019-03/documents/at... That's only 2.1% of 6000. If we lower capital cost without lowering O&M, we get 4.2% of 3000. That puts a small amount of nuclear back in the US market. However, they default to a discount rate of 10 for nuclear, and only 5 for wind/solar/battery. I don't see any reason to use different numbers here. Setting nuclear to 5, with the above changes, gets us back to a 100% nuclear US grid. Even if we take O&M back up to 6%, a capital cost of 3000 and discount rate of 5% means a 100% nuclear US. Comparing overall grid cost of two examples: With no nuclear (due to 10% discount), the US average grid cost is 53.7 EUR/MWh. With 100% nuclear (due to 5% discount and 3000 capital cost), the US grid cost is 48.6 EUR/MWh. In any case, this has changed my view somewhat. I'd thought that nuclear was a clear winner over storage, but it looks like nuclear's place is at least marginal in the US. We have copious wind and solar, and nuclear only lowers overall grid cost if we can manage the sort of nuclear costs they've achieved in South Korea. But in countries less favorable to wind/solar, nuclear dominates.