From a grid stability point, you can’t produce more than is used, else you get higher frequencies and/or voltages until the automatics shut down. It’s already a somewhat frequent occurence in germany for the grid operator to shut down big solar plants during peak hours because they produce way more power than they can dump (because of low demand or the infrastructure limiting transfer to somewhere else)
Negative prices are the grid operator encouraging more demand so it can balance out the increased production.
As someone with a technical background this is the stupidest problem with solar that I don’t get… just turn off the panels in groups until generation is closer to demand… how have engineers not figured that out. And if they have why does this still get written about.
I’m in solar/BESS, and I mean more and more DER sites are making use of string inverters which break out arrays into greater chunks than with central inverters. With those, you have more granularity of control where you can drop entire blocks/strings at a time to fall to your curtailed export rate.
You might ask yourself though why DERs can’t just ramp inverter outputs up or down to match curtailment automatically across a whole site. You can absolutely do that, but what happens is your solar or wind resource stays high on the DC or low frequency (LF) AC side, respectively, while power frequency AC is low on the other side of the inverters. This is referred to as DC:AC ratio in the biz, and the higher that ratio, the more losses your inverters experience and less efficient they are. This also puts a huge strain on your inverters and can lessen their operational lifetime.
But really, DERs tie into the grid at distribution level and so they don’t fall under the regulations of FERC & NERC (at least in North America). This means that smaller producers don’t have the same requirements for control as do utility-scale players, so the incentive to control these string inverters at that granular level isn’t there. It’s much easier to just trip the main breaker and wait until the utility gives you the go ahead to turn back on.
I suspect that at lot of producers may want to look into greater control capabilities in the future, but this also depends on inverter OEMs too allowing that control.
From a grid stability point, you can’t produce more than is used, else you get higher frequencies and/or voltages until the automatics shut down. It’s already a somewhat frequent occurence in germany for the grid operator to shut down big solar plants during peak hours because they produce way more power than they can dump (because of low demand or the infrastructure limiting transfer to somewhere else)
Negative prices are the grid operator encouraging more demand so it can balance out the increased production.
As someone with a technical background this is the stupidest problem with solar that I don’t get… just turn off the panels in groups until generation is closer to demand… how have engineers not figured that out. And if they have why does this still get written about.
Someone is an idiot. Maybe it’s me?
I’m in solar/BESS, and I mean more and more DER sites are making use of string inverters which break out arrays into greater chunks than with central inverters. With those, you have more granularity of control where you can drop entire blocks/strings at a time to fall to your curtailed export rate.
You might ask yourself though why DERs can’t just ramp inverter outputs up or down to match curtailment automatically across a whole site. You can absolutely do that, but what happens is your solar or wind resource stays high on the DC or low frequency (LF) AC side, respectively, while power frequency AC is low on the other side of the inverters. This is referred to as DC:AC ratio in the biz, and the higher that ratio, the more losses your inverters experience and less efficient they are. This also puts a huge strain on your inverters and can lessen their operational lifetime.
But really, DERs tie into the grid at distribution level and so they don’t fall under the regulations of FERC & NERC (at least in North America). This means that smaller producers don’t have the same requirements for control as do utility-scale players, so the incentive to control these string inverters at that granular level isn’t there. It’s much easier to just trip the main breaker and wait until the utility gives you the go ahead to turn back on.
I suspect that at lot of producers may want to look into greater control capabilities in the future, but this also depends on inverter OEMs too allowing that control.