Note that EV as grid batteries is possible with Tesla, VW and as mentioned F 150. However regulations of utilities do not generally allow sharing the savings. The home owner must purchase additional hardware for the home to make use of EV grid storage. It would be a short payback but needs to be in place. Tesla does not promote this feature as it is incomplete without regulations permitting it’s use. Tesla’s auto bidder software could be used today, the same way it’s mega packs are used to save money for utilities.