Comment by epistasis

What do you mean by long stretches? Are you talking about sundown to sunset?

In many (most?) areas, wind picks up at night, wind can't really be "local", and demand is lower at night time so that's a great use for the grid.

Also, batteries are getting so cheap that people are putting multiple days' worth of storage on wheels, driving them around, and parking them at home during the evening peak and overnight.

When they are that cheap, adding 10-20 kWh of local storage is going to pay for itself in no time.

When my neighbor is overproducing solar during the day, that means that he's sending his power over to my house, which doesn't have solar. Which means that my neighborhood is pulling down less peak power. And the grid is sized for peak power, not for minimal power, so whenever that peak is lowered, it saves me money but costs the utility profits.

Because the utility gets to recoup a fixed profit rate off of any amount of grid they are allowed by the PUC to install, whether it was needed or not. My neighbor, with the solar, also pays lots of fees for the privilege of sending me power and requiring less grid.

This effect of shaving the peak is so extreme that solar causes the California duck curve. Though the storage that's been added in just the past two years has pretty much solved any problems needed for the evening ramp as the sun goes down, now.