I have solar panels and a Tesla battery and belong to a VPP (Virtual Power Plant). Now that the feed-in tariffs have dropped so low, is it quite feasible to add a second battery in order to reduce the need to send power to the grid? Is it possible that a second battery can be that inside an electric car where there is bi-directional current flow - so that your house can be powered by the car battery in times of need, all in conjunction with the VPP?
