Very true. If you're pushing power out onto the grid, you're no longer a consumer but rather a producer and there are other issues that come into play.
Twenty, thirty years ago the amount of power from rooftop installations being pushed out onto the grid was minimal compared to the size of the grid and it wasn't an issue.
If you had an energy producer that was producing 10% of the power and doing significant swings in its production without participating on the wholesale energy market (and not signaling those swings)... the regulators would have shut them down.
But when you've got 10,000 people each contributing 0.001% of the grid power (and all having the same swings)... and not participating on the wholesale market and not signaling their swings, that can be disruptive (and damaging).
Twenty, thirty years ago the amount of power from rooftop installations being pushed out onto the grid was minimal compared to the size of the grid and it wasn't an issue.
If you had an energy producer that was producing 10% of the power and doing significant swings in its production without participating on the wholesale energy market (and not signaling those swings)... the regulators would have shut them down.
But when you've got 10,000 people each contributing 0.001% of the grid power (and all having the same swings)... and not participating on the wholesale market and not signaling their swings, that can be disruptive (and damaging).
https://learn.pjm.com/electricity-basics/market-for-electric... is also a good read and https://www.pjm.com/markets-and-operations.aspx is the live market for that part of the grid.