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Renewables can absolutely provide and consume reactive power through the use of power electronics equipment incorporated into the inverters. All modern utility-

Renewables can absolutely provide and consume reactive power through the use of power electronics equipment incorporated into the inverters. All modern utility-scale wind and solar power plants use this type of equipment, and most interconnection requirements in the US require significant reactive power capability as part of the interconnection process. This may require additional reactive power capabilities such as capacitor banks, DVAR units, or reactors at the project substation. This means if grid voltage drops they will provide VARs to increase voltage, and vice versa. They can similarly react to shifts in grid frequency. Only after they reach certain power factor, voltage, or frequency limits will they disconnect from the grid, similar to other generators. If in spain renewable energy projects were somehow exempted from needing to provide a wide range of power factor capability then yes this would be a rules problem. They charge more for inductive loads because of low power factors and significant VAR consumption yes, though you can also do power factor correction on induction motors. 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. Also, islanding means operating as a standalone grid, which does not happen when the generators shut down, and systems are designed to shut down after a certain number of cycles without grid. This does not sound like islanding at all.

cogman10 1y ago
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.

cogman10 1y ago

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.