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beachy | on: Bidirectional charging during grid outages
We have frequent power cuts and follow this same philosophy.

Our first line of defence is the solar system's battery. When power goes out, that will keep things running for some time with the big optional loads switched off - e.g. hot tub, hot water cylinder and pool.

If the sun's shining we can run like this for a long time.

In a solar drought, when the solar battery runs low, the next step is to plug the EV in via V2L and use it as a generator to charge the solar battery. EVs have comparatively huge batteries, so at the cost of losing mobility, which may be important in an emergency, this will keep things going for even longer.

One great feature of using an EV is you can drive to a fast charger, charge up in an hour, and transport all that energy back home.

The final fallback is to plug the 2KW petrol generator in to charge the solar battery. This is enough to keep things going forever assuming a petrol supply. A petrol generator is nicely portable and can be loaned to less prepared neighbours who likely have their own petrol.

The key to it all is the solar battery. That gives you uninterrupted power while mucking around with the alternate sources. It doesn't even have to be all that large if you have an EV.

spockz | parent
In the scenario mentioned in the GP post where a giant tropical storm hit resetting the grid for 7+ days, how big is the chance that your solar panels installation has survived? Also, if the grid is gone, won’t the fast chargers also be out of service?

Don’t get me wrong, I think you’re right for most cases but I also think for some more end of the world type of scenarios there is little that beats a generator and stored fuel.

namibj | root | parent | next
If you can stay there (no evacuation for building doesn't seal enough to make it habitable), most of the solar should have survived. Moving a broken panel out of the way and swapping one from the end of the array in to make the cables fit, or even having a spare jumper cable to swap in place of a broken panel, is quite easy to do. Mostly just make sure there's no load current at all on the string when you disconnect the MC4 connector with the special tool that keeps uneducated people from unplugging them under load and getting greeted with a persistent low current (not "arc flash", we're in the region of "high powered welder used with just normal welding PPE") DC arc (that may supply several hundred volts for a long drawn out burn). As long as it's around substantially below 500 mA you're not gonna sustain an arc.
beachy | root | parent
Indeed, that's why I mentioned petrol generator as the last level of backup.

Though the most recent big tropical storm we had a few years ago, the power was out for 3 days, it was dark and cloudy obviously so no solar, the local petrol pumps had no power and the roads were blocked with fallen trees so we couldn't even drive anywhere. In that situation it really is candles and cooking on wood fires once the petrol runs dry.