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by shagie 1250 days ago
At an hour or two, that's ballpark 3kWh of power you'd need. There are battery backup solutions in this range that are $3k to $6k (that are frankly quite interesting.

Those have the instant on design so that if the power is lost to the house you have a few seconds and its back up and running.
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dahfizz 1250 days ago
But why would I waste an extra $5k and floor space in my garage if _I already have an EV that should be able to do this_.
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shagie 1250 days ago
You may not be at home during the power outage. This could impact things such as aquarium support, home security, or cold food storage.

You may need additional equipment or an upgrade to existing equipment to do the power outage cut over. To do this (and not just support an outlet from the vehicle), it is necessary to remove the house from the grid for the duration - suddenly changing phases can damage equipment (e.g. when the power comes back on). Additionally, if you were still connected to the grid, it would mean that your batteries are trying to support the portion of the entire grid (which it will fail badly at).

This also depends on the equipment that you currently have. Not everyone has a battery backup Tesla power wall. If you are plugging the car into 120v or 240v outlets, that doesn't have the circuitry to support isolation of the house from the grid after a power outage and the wiring for the 120v or 240v outlet isn't heavy enough to support the current draw for the rest of the house even if it was isolated.

You may also decide that trying to do it from the car, while possible, is a bad idea. https://electrek.co/2021/02/23/tesla-voids-your-warranty-pow... and https://www.tesla.com/sites/default/files/downloads/tesla-ne...

> This New Vehicle Limited Warranty does not cover any vehicle damage or malfunction directly or indirectly caused by, due to or resulting from normal wear or deterioration, abuse, misuse, negligence, accident, improper maintenance, operation, storage or transport, including, but not limited to, any of the following:

> ...

> Using the vehicle as a stationary power source

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