Sure, I can sell that electricity to the grid and earn 7¢, but if I buy it back later I have to pay 28¢ per kWh. So instead, when the sun is shining and I see too much production on my Sense display I turn things on, the dishwasher, the washing machine... When there is still more solar I start the cars charging. Not until all the work is done and all the cars are charged do I let the power go out to the grid, some days that's more than 30 kWhs that I am generating and using. As the sun starts to set, and production is below demand I start winding down usage. Even when it's just a large cloud, I can pause the washer, I can even pause a car charging by using my phone when I am across town. Someday I hope Sense will do that job for me.