24 ms·

This is so often under appreciated. For reference, non-FF capacity factors here: https://www.eia.gov/electricity/monthly/epm_table_grapher.php?t=epmt_6_07_b ht

This is so often under appreciated. For reference, non-FF capacity factors here: https://www.eia.gov/electricity/monthly/epm_table_grapher.php?t=epmt_6_07_b https://www.eia.gov/electricity/monthly/epm_table_grapher.ph... So you’re probably looking at a 2-3x difference between renewable nameplate capacity and the equivalent replaced fossil fuels.

jacquesm 4y ago
Fossil also has downtime, as does nuclear. It just isn't as frequent. But in some cases (reactor shutdown for instance) it can be much more sudden and long than the way wind and solar vary. And prediction of near future solar/wind availability is getting better all the time helping a lot in dealing with the variability.
- acidburnNSA 4y ago
  Average is what matters here when you're on the grid. Nuclear capacity factor averages 92% in the US. Solar averages 25%. Wind 35.
  - jacquesm 4y ago
    I've been 100% off grid for two consecutive years in Northern Canada. We did have a backup generator but it wasn't used after the windmill went up. 48 KWh of storage was enough to tide us over any period without sun/wind.
    - aeyes 4y ago
      What kind of windmill do you have? I did some research to see if it would make sense as a homeowner and found it to be mostly not worth it. You shouldn't attach it directly to the building because wind speed near surfaces slows down significantly. So you need a large pole which will make maintenance very expensive. You usually can't attach the pole directly to the building either because it isn't rated for such high forces. Wind mills are also quite noisy so you probably want to have a huge amount of land to put it far away from the house. The power produced rises to the power of two with the diameter of the rotor and to the power of three with wind speed. This means that you want an installation which is both large and high.
      - jacquesm 4y ago
        I built my own. 16' diameter, variable pitch, and silent as can be. The noise a windmill makes is closely related to the thickness of the trailing edge of the blades.
        coda_ 4y ago
        Have you done any write ups or posts on your build? Or do you have any suggestions of other posts about similar builds? Would love to learn more about what it takes to do this.
        jacquesm 4y ago
        Absolutely. Part II has the diagrams and pretty much everything else. If you build one let me know! https://jacquesmattheij.com/how-to-build-a-windmill/ https://jacquesmattheij.com/how-to-build-a-windmill/
  - ZeroGravitas 4y ago
    Why does it matter though? Are coal plants better because they have higher capacity factors? Are they cheaper to run? I mean obviously if you compare two coal plants that are otherwise identical, you'd assume the higher capacity leads to cheaper power and is therefore better. But once you are comparing coal to solar, its utterly meaningless out of context. Even in the near identical coal case, why not say "this one is cheaper" or some other measurement people actually care about?
    - dahfizz 4y ago
      Coal plants aren't "better", but they work when its dark and not windy. We need _something_ to fill that (rather large) niche.

jacquesm 4y ago

Fossil also has downtime, as does nuclear. It just isn't as frequent. But in some cases (reactor shutdown for instance) it can be much more sudden and long than the way wind and solar vary. And prediction of near future solar/wind availability is getting better all the time helping a lot in dealing with the variability.

acidburnNSA 4y ago
Average is what matters here when you're on the grid. Nuclear capacity factor averages 92% in the US. Solar averages 25%. Wind 35.
- jacquesm 4y ago
  I've been 100% off grid for two consecutive years in Northern Canada. We did have a backup generator but it wasn't used after the windmill went up. 48 KWh of storage was enough to tide us over any period without sun/wind.
  - aeyes 4y ago
    What kind of windmill do you have? I did some research to see if it would make sense as a homeowner and found it to be mostly not worth it. You shouldn't attach it directly to the building because wind speed near surfaces slows down significantly. So you need a large pole which will make maintenance very expensive. You usually can't attach the pole directly to the building either because it isn't rated for such high forces. Wind mills are also quite noisy so you probably want to have a huge amount of land to put it far away from the house. The power produced rises to the power of two with the diameter of the rotor and to the power of three with wind speed. This means that you want an installation which is both large and high.
    - jacquesm 4y ago
      I built my own. 16' diameter, variable pitch, and silent as can be. The noise a windmill makes is closely related to the thickness of the trailing edge of the blades.
      - coda_ 4y ago
        Have you done any write ups or posts on your build? Or do you have any suggestions of other posts about similar builds? Would love to learn more about what it takes to do this.
        jacquesm 4y ago
        Absolutely. Part II has the diagrams and pretty much everything else. If you build one let me know! https://jacquesmattheij.com/how-to-build-a-windmill/ https://jacquesmattheij.com/how-to-build-a-windmill/
- ZeroGravitas 4y ago
  Why does it matter though? Are coal plants better because they have higher capacity factors? Are they cheaper to run? I mean obviously if you compare two coal plants that are otherwise identical, you'd assume the higher capacity leads to cheaper power and is therefore better. But once you are comparing coal to solar, its utterly meaningless out of context. Even in the near identical coal case, why not say "this one is cheaper" or some other measurement people actually care about?
  - dahfizz 4y ago
    Coal plants aren't "better", but they work when its dark and not windy. We need _something_ to fill that (rather large) niche.