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Good comment and I do not disagree. I wasn't aware that the US had significant reactive power requirements (I'm guessing for utility scale solar). > And thoug

Good comment and I do not disagree. I wasn't aware that the US had significant reactive power requirements (I'm guessing for utility scale solar). > And though most wind turbines use induction generators, they are designed to be able to supply power at unity power factor and through a large power factor range. Correct me if I'm wrong, but I was under the impression that wind turbines did an AC->DC->AC dance to ultimately get the right power factors and frequencies.

xenadu02 1y ago
Rooftop Solar in the US has had such requirements for a long time. More recent systems in CA like mine (IIRC starting in 2018) require an active connection to the grid operator so the operator can override the default exceedance values to permit larger excursions for longer to avoid a cascade where grid instability causes lots of solar capacity to trip, causing further instability, leading to collapse. They can also command solar to stop providing power to the grid if there is an excess in the other direction though legally there is a limit to how often they can do that and for how much total time.
- AtlasBarfed 1y ago
  Would home storage buffers help? Alt energy really needs salt water batteries to scale production so that a multi day amount of storage is around a thousand USD.
  - xenadu02 1y ago
    > Would home storage buffers help? Yes. I actually have 20kWh battery storage on my home. It provides backup power and covers our needs during hours of peak pricing. In theory NEM3 in California was supposed to encourage installation of battery storage but was instead a give-away to utilities because they never actually implemented any reasonable benefits. Under NEM3 they force you to give away electricity to utilities essentially for free so now solar only makes sense if you have storage deployed with it.
scblock 1y ago
That is correct. There are no modern utility scale turbines that are directly coupled to the grid. This was at least initially to allow for variable rotor speed at a constant grid frequency. Some use doubly-fed induction generators which take about 1/3 of the power through an inverter at variable frequency back through the rotor to create stable 50 or 60 Hz output (Type 3 machines), while others do full scale conversion (Type 4 machines)[1]. FERC 827[2] details the power factor requirements in the US for non-spinning (mostly renewable) generators, most easily summarized as power factors from 0.95 lagging to 0.95 leading at the high side of the transformer in the project substation. [1]: https://www.esig.energy/wiki-main-page/wind-turbine-technologies/ https://www.esig.energy/wiki-main-page/wind-turbine-technolo... [2]: https://www.ferc.gov/sites/default/files/2020-06/RM16-1-000.pdf https://www.ferc.gov/sites/default/files/2020-06/RM16-1-000....
kragen 1y ago
> I wasn't aware that the US had significant reactive power requirements (I'm guessing for utility scale solar). Yes, you were. The article says: > Yet “other operators, such as in the U.S., require or reward grid participants for helping balance this reactive power,” Lara says. Spain could do that, too, given its commitment to expanding the role of renewable, and therefore distributed, power.

xenadu02 1y ago

Rooftop Solar in the US has had such requirements for a long time. More recent systems in CA like mine (IIRC starting in 2018) require an active connection to the grid operator so the operator can override the default exceedance values to permit larger excursions for longer to avoid a cascade where grid instability causes lots of solar capacity to trip, causing further instability, leading to collapse. They can also command solar to stop providing power to the grid if there is an excess in the other direction though legally there is a limit to how often they can do that and for how much total time.

AtlasBarfed 1y ago
Would home storage buffers help? Alt energy really needs salt water batteries to scale production so that a multi day amount of storage is around a thousand USD.
- xenadu02 1y ago
  > Would home storage buffers help? Yes. I actually have 20kWh battery storage on my home. It provides backup power and covers our needs during hours of peak pricing. In theory NEM3 in California was supposed to encourage installation of battery storage but was instead a give-away to utilities because they never actually implemented any reasonable benefits. Under NEM3 they force you to give away electricity to utilities essentially for free so now solar only makes sense if you have storage deployed with it.

scblock 1y ago

That is correct. There are no modern utility scale turbines that are directly coupled to the grid. This was at least initially to allow for variable rotor speed at a constant grid frequency. Some use doubly-fed induction generators which take about 1/3 of the power through an inverter at variable frequency back through the rotor to create stable 50 or 60 Hz output (Type 3 machines), while others do full scale conversion (Type 4 machines)[1]. FERC 827[2] details the power factor requirements in the US for non-spinning (mostly renewable) generators, most easily summarized as power factors from 0.95 lagging to 0.95 leading at the high side of the transformer in the project substation. [1]: https://www.esig.energy/wiki-main-page/wind-turbine-technologies/ https://www.esig.energy/wiki-main-page/wind-turbine-technolo... [2]: https://www.ferc.gov/sites/default/files/2020-06/RM16-1-000.pdf https://www.ferc.gov/sites/default/files/2020-06/RM16-1-000....

kragen 1y ago

> I wasn't aware that the US had significant reactive power requirements (I'm guessing for utility scale solar). Yes, you were. The article says: > Yet “other operators, such as in the U.S., require or reward grid participants for helping balance this reactive power,” Lara says. Spain could do that, too, given its commitment to expanding the role of renewable, and therefore distributed, power.