6 ms·

How many GW of wind, solar, and nuclear can we bring online in the next 28 years?

ben_w 4y ago
In 2021, we added this many new gigawatts: 183 PV[0], 100 wind[1], 7.88 nuclear (but 8.6 nuclear was also shut down)[2] 28 times that, ignoring the shutdowns (I don't actually know how long wind lasts, IIRC nuclear is "about 50-70 years" and PV is "about 30 years"), gives a total of: 5124 GW PV, 2800 GW wind, 218 GW nuclear. But that's a lower bound for PV, as that's growing with what looks like an approximately exponential long-term trend (since 1992) of 36.5% per year. While such a growth rate is physically possible to maintain for 28 years even without going into space, given that if we did make so much we wouldn't merely give everyone an American lifestyle but also be able to get the entire human population continuously flying[3], I'm assuming it will turn into a sigmoid before then. [0] https://en.wikipedia.org/wiki/Growth_of_photovoltaics https://en.wikipedia.org/wiki/Growth_of_photovoltaics [1] https://en.wikipedia.org/wiki/Wind_power https://en.wikipedia.org/wiki/Wind_power [2] https://en.wikipedia.org/wiki/List_of_commercial_nuclear_reactors https://en.wikipedia.org/wiki/List_of_commercial_nuclear_rea... [3] https://www.wolframalpha.com/input?i=%28105*1.365%5E%2828%2B2021-1992%29+MW%29+%2F+10+billion https://www.wolframalpha.com/input?i=%28105*1.365%5E%2828%2B...
- mlyle 4y ago
  The thing is, 183GW from PV is like 20-30GW of nuclear, because nuclear's capacity factor is near 100% and PV's is often near 10%. Storage seems hard and expensive. We're going to need a whole lot of approaches: - Wind taking a bigger share of renewables - Whatever storage we can reasonably build, including some exotic stuff like power-to-gas-to-power. - Nuclear filling in a little bit - PV comically overbuilt and routinely throwing away a lot of power midday on most days. - Still peaking off natural gas, a little bit.
  - ncmncm 4y ago
    Renewables' capacity factor is much greater than 10%, in practice. If you need falsehoods to make your case, you have no case.
    - mlyle 4y ago
      > > The thing is, 183GW from PV is like 20-30GW of nuclear, because nuclear's capacity factor is near 100% and PV's is often near 10%. > Renewables' capacity factor is much greater than 10%, in practice. If you need falsehoods to make your case, you have no case. Residential/commercial PV -- e.g. rooftop solar-- very often is 10% or less. If you want to only look at utility-scale fixed tilt, instead, recent deployments average near (not quite) 20%. https://emp.lbl.gov/pv-capacity-factors https://emp.lbl.gov/pv-capacity-factors Nuclear's capacity factor is 93%. In which case, 183GW from utility-scale, fixed-tilt PV is like 183/.93 * .20 = 39GW. Which, admittedly, is outside of my range of 20-30, but also relies on generous assumptions (utility scale projects only-- which are only ~25% of US solar wattage). If you consider only tracking, you can get all the way to 49GW, which still doesn't eliminate the point. Perhaps the bigger point is looking at the eastern seaboard. Shipping power 2000 miles is not super practical for various reasons, and the capacity factors for a whole region of the US are pretty poor.
      - r00fus 4y ago
        How much solar capacity is actually residential? I'd say quite small since solar is hard to deploy residential + lack of home value improvement. Nuclear should be part of the equation (it has it's own issues with wastewater) but if adding nuclear means not investing equally or more in solar/wind renewables, that's completely misguided.
        mlyle 4y ago
        > How much solar capacity is actually residential? I'm not sure how much is residential, but about 25% is utility-scale projects. The rest is stuff on commercial buildings and homes-- which have an average capacity factor around 12%. > Nuclear should be part of the equation (it has it's own issues with wastewater) but if adding nuclear means not investing equally or more in solar/wind renewables, that's completely misguided. I totally agree. I think our priorities should be, in order: - Wind - Pumped storage - Improved utility interties - Demand-side management - PV - Nuclear - Battery storage - Electrolyzers, etc But even the lowest priority item should be aggressively pursued.
  - ben_w 4y ago
    Even at 10% capacity factor, and with a sudden cessation of the long term exponential trend in PV, and assuming the 2021 numbers for new nuclear power while ignoring that more was shut down, that still leaves more than twice as much new PV as new nuclear.
    - mlyle 4y ago
      Sure, but I think we already know that we build a lot more PV than nuclear. The question is, should we build a bit more nuclear? Even a small change would be equivalent to a lot of PV production, and provide power at times when PV can't.
      - ben_w 4y ago
        Well on that point I agree completely, although mainly because I think it's a good idea to have a diversity of supply and not because it's the most cost effective. From what I've seen, the cheapest solution is a few square meters' cross section of HVDC encircling the planet, but that would almost certainly take a big increase in global metal mining even on these time scales and even when ignoring the political issues.
  - aidenn0 4y ago
    For the USA, utility scale PV runs at a capacity factor of over 25% in the sunbelt and mid teens elsewhere. I suppose that may qualify as "often near 10%" but I think you are overstating it a bit, as really household PV is the only one that really is around 10%.
    - mlyle 4y ago
      See https://news.ycombinator.com/item?id=31755603 https://news.ycombinator.com/item?id=31755603 Note non-utility scale solar is 75% of the installed watts, too-- so you have a huge share of it pulling towards that 10-12% number.
  - r00fus 4y ago
    PV throwing off excess during peak is fine - if we have storage. Storage is has only recently become feasible, it would likely be utility-grade storage, Powerwall/home storage or Vehicle2Grid integration by the 2050 timeframe. Storage cost being excessive means it's early adoption timeframe. As the need for it becomes clear options will open up.
    - mlyle 4y ago
      > PV throwing off excess during peak is fine PV throwing off excess during peak is fine even if we don't have storage, because it means PV is adequate for a bigger fraction of the morning and evening (and in turn, the needs for storage become a little less because of the over-provisioning of production).
    - ncmncm 4y ago
      Storage is cheap and getting cheaper even faster than solar. Batteries will only ever be a tiny fraction of storage.

In 2021, we added this many new gigawatts: 183 PV[0], 100 wind[1], 7.88 nuclear (but 8.6 nuclear was also shut down)[2] 28 times that, ignoring the shutdowns (I don't actually know how long wind lasts, IIRC nuclear is "about 50-70 years" and PV is "about 30 years"), gives a total of: 5124 GW PV, 2800 GW wind, 218 GW nuclear. But that's a lower bound for PV, as that's growing with what looks like an approximately exponential long-term trend (since 1992) of 36.5% per year. While such a growth rate is physically possible to maintain for 28 years even without going into space, given that if we did make so much we wouldn't merely give everyone an American lifestyle but also be able to get the entire human population continuously flying[3], I'm assuming it will turn into a sigmoid before then. [0] https://en.wikipedia.org/wiki/Growth_of_photovoltaics https://en.wikipedia.org/wiki/Growth_of_photovoltaics [1] https://en.wikipedia.org/wiki/Wind_power https://en.wikipedia.org/wiki/Wind_power [2] https://en.wikipedia.org/wiki/List_of_commercial_nuclear_reactors https://en.wikipedia.org/wiki/List_of_commercial_nuclear_rea... [3] https://www.wolframalpha.com/input?i=%28105*1.365%5E%2828%2B2021-1992%29+MW%29+%2F+10+billion https://www.wolframalpha.com/input?i=%28105*1.365%5E%2828%2B...

mlyle 4y ago
The thing is, 183GW from PV is like 20-30GW of nuclear, because nuclear's capacity factor is near 100% and PV's is often near 10%. Storage seems hard and expensive. We're going to need a whole lot of approaches: - Wind taking a bigger share of renewables - Whatever storage we can reasonably build, including some exotic stuff like power-to-gas-to-power. - Nuclear filling in a little bit - PV comically overbuilt and routinely throwing away a lot of power midday on most days. - Still peaking off natural gas, a little bit.
- ncmncm 4y ago
  Renewables' capacity factor is much greater than 10%, in practice. If you need falsehoods to make your case, you have no case.
  - mlyle 4y ago
    > > The thing is, 183GW from PV is like 20-30GW of nuclear, because nuclear's capacity factor is near 100% and PV's is often near 10%. > Renewables' capacity factor is much greater than 10%, in practice. If you need falsehoods to make your case, you have no case. Residential/commercial PV -- e.g. rooftop solar-- very often is 10% or less. If you want to only look at utility-scale fixed tilt, instead, recent deployments average near (not quite) 20%. https://emp.lbl.gov/pv-capacity-factors https://emp.lbl.gov/pv-capacity-factors Nuclear's capacity factor is 93%. In which case, 183GW from utility-scale, fixed-tilt PV is like 183/.93 * .20 = 39GW. Which, admittedly, is outside of my range of 20-30, but also relies on generous assumptions (utility scale projects only-- which are only ~25% of US solar wattage). If you consider only tracking, you can get all the way to 49GW, which still doesn't eliminate the point. Perhaps the bigger point is looking at the eastern seaboard. Shipping power 2000 miles is not super practical for various reasons, and the capacity factors for a whole region of the US are pretty poor.
    - r00fus 4y ago
      How much solar capacity is actually residential? I'd say quite small since solar is hard to deploy residential + lack of home value improvement. Nuclear should be part of the equation (it has it's own issues with wastewater) but if adding nuclear means not investing equally or more in solar/wind renewables, that's completely misguided.
      - mlyle 4y ago
        > How much solar capacity is actually residential? I'm not sure how much is residential, but about 25% is utility-scale projects. The rest is stuff on commercial buildings and homes-- which have an average capacity factor around 12%. > Nuclear should be part of the equation (it has it's own issues with wastewater) but if adding nuclear means not investing equally or more in solar/wind renewables, that's completely misguided. I totally agree. I think our priorities should be, in order: - Wind - Pumped storage - Improved utility interties - Demand-side management - PV - Nuclear - Battery storage - Electrolyzers, etc But even the lowest priority item should be aggressively pursued.
- ben_w 4y ago
  Even at 10% capacity factor, and with a sudden cessation of the long term exponential trend in PV, and assuming the 2021 numbers for new nuclear power while ignoring that more was shut down, that still leaves more than twice as much new PV as new nuclear.
  - mlyle 4y ago
    Sure, but I think we already know that we build a lot more PV than nuclear. The question is, should we build a bit more nuclear? Even a small change would be equivalent to a lot of PV production, and provide power at times when PV can't.
    - ben_w 4y ago
      Well on that point I agree completely, although mainly because I think it's a good idea to have a diversity of supply and not because it's the most cost effective. From what I've seen, the cheapest solution is a few square meters' cross section of HVDC encircling the planet, but that would almost certainly take a big increase in global metal mining even on these time scales and even when ignoring the political issues.
- aidenn0 4y ago
  For the USA, utility scale PV runs at a capacity factor of over 25% in the sunbelt and mid teens elsewhere. I suppose that may qualify as "often near 10%" but I think you are overstating it a bit, as really household PV is the only one that really is around 10%.
  - mlyle 4y ago
    See https://news.ycombinator.com/item?id=31755603 https://news.ycombinator.com/item?id=31755603 Note non-utility scale solar is 75% of the installed watts, too-- so you have a huge share of it pulling towards that 10-12% number.
- r00fus 4y ago
  PV throwing off excess during peak is fine - if we have storage. Storage is has only recently become feasible, it would likely be utility-grade storage, Powerwall/home storage or Vehicle2Grid integration by the 2050 timeframe. Storage cost being excessive means it's early adoption timeframe. As the need for it becomes clear options will open up.
  - mlyle 4y ago
    > PV throwing off excess during peak is fine PV throwing off excess during peak is fine even if we don't have storage, because it means PV is adequate for a bigger fraction of the morning and evening (and in turn, the needs for storage become a little less because of the over-provisioning of production).
  - ncmncm 4y ago
    Storage is cheap and getting cheaper even faster than solar. Batteries will only ever be a tiny fraction of storage.