Please consider installing a 110v manual generator transfer switch so you can turn your EV car into a small backup generator during PG&E's PSPS. Once you have the switch setup, you can simply connect your car to the switch via an extension cord + inverter and you will be able to power 4 circuits to the house. While the power you can put out is limited, but you can make the house last a long time with the big batteries that are in the vehicle. Obviously the cheapest way is to install an inverter off the 12v directly, but you could also go through something like a Goal Zero portable battery to limit the risk of any damage. You would end up creating a setup where you are charging the Goal Zero with your EV while the Goal Zero is powering the house. Depending on what you are pulling, a parked Model S charged with 80% can probably make an energy star rated full size fridge for a week!