1) They go down but not to zero. Consider a hypothetical person with excess solar and a large power bank, they still cost money to serve and build reserve capacity for when events require them to pull from the grid.
2) They don't and there was a LOT of complaining about not getting paid full rates by early solar adopters.
3) I'm fine with it. The power grid is one of the natural monopolies where state operation makes more sense than the weird quasi private marketless mess we have now and progressive tax structures are normal there so I don't see as much problem with income related grid fees. Also higher income people will generally have larger grid demands meaning they need more excess capacity built in so they probably do cost more to serve.
2) They don't and there was a LOT of complaining about not getting paid full rates by early solar adopters.
3) I'm fine with it. The power grid is one of the natural monopolies where state operation makes more sense than the weird quasi private marketless mess we have now and progressive tax structures are normal there so I don't see as much problem with income related grid fees. Also higher income people will generally have larger grid demands meaning they need more excess capacity built in so they probably do cost more to serve.