[Snax]

Well, regardless of costs and what is 'free', I'm looking to get my setup to the point where my EV is net zero from the off-grid secondary system I am implementing. I think that is going to be pretty close to do-able with two Model S modules and 1.2kW of panels on the roof.

No, the panels won't deliver enough power to top off my car every day, but there's probably 5 days a month that I simply don't go anywhere more than a mile or two from the house.

Honestly, it's not the best use of the panel resource in the context of the grid as a battery, but like I said at the start, this is also a backup for if/when SHTF with an earthquake or other less likely disaster. If I thought that was never going to happen, I'd just be expanding the current grid-tie directly.

It is possible to take advantage of the battery in my i3 for emergency power, but without a backup system, I'd have no way to charge over an extended period of time. Seriously, it could be MONTHS without power here if the quake is as strong as it is predicted it could be at 9.0.

To put that in perspective: 100x the shaking of the Northridge quake for multiple times as long. There will NO infrastructure left if that is the case. Probably be lucky if any of our backup plan is usable at that point as well. :P