Find out what a battery could cost, what incentives are available to you and how it could affect your electricity bills. SDG&E cut what it pays you for midday solar again. From about 10 to 2, when your panels are producing the most, that's now when the utility pays you the least for it. And from 4 to 9, when you're home and using power, they still charge their highest rates of the day. So the deal is: sell them your power cheap at noon, buy it back at the highest price at dinner.