A powerwall has what, 12ish KW usable (less in reality) which a single one can power a house for for up to a day if you're careful about what you're using. If you scale that up to the 75KW+ batteries being put into EVs today buying an inverter could be a good investment if you live in an area with frequent power outages (or a cabin or whatnot).
There was also some talk about Teslas being able to send power back to the house with the new HPWC - not sure if that ever happened.
There was also some talk about Teslas being able to send power back to the house with the new HPWC - not sure if that ever happened.