I just simply can't imagine. Can not compute this behavior.
If APS (the state power company) were to announce this sort of thing the peasants would oil up their pitchforks and AK 47s and head for the castle walls. Literally.
Not that APS is without fault. The Public Corporation Commission which is the regulatory body in AZ is a wholly owned subsidiary of APS. 3 person board elected by the general public. APS contributes to the campaign of at least two in every election.
Right now they are diddling with home solar, which is very popular and efficient here. If you generate more power than you can use they pay you just under half of what they pay wholesale for excess power. And you have no choice. It is against the law to vent excess power, you have to buy their switch gear AND sell any excess to them. They make 100% on every KWH they are 'forced to buy'. All most all of the solar power generated in AZ (and that total is considerable. 3 of the top 10 solar projects on earth are in AZ) is sold to California. Because they passed a referendum that the entire state needed to be powered 33% by renewable in 2018. It goes up from there :)
Power companies. If I could afford it, I'd put up the panels and go off the grid. I could use the excess power that I'd generate to grow pot so I wouldn't have to vent any.