Charging batteries for those cars is not “free.” It’s rather expensive.
I’ve seen hybrids stalled next to two-lane highways at high elevations on the Rockies. Haven’t seen any of them driving far from any town in the winter. The batteries won’t take much of a charge in extreme cold, unless some expensive shelter, heating and ventilation are built for them (temps lower than -30, F).
An off-grid PV solar plant for charging an electric car at an off-grid home would be large and expensive indeed. Maybe a few coal-fired boilers, custom steam engines and large alternators could be built to do the job—similar to the answer of charging electric cars from grid power. ;-)
Interesting energy problems with extreme cold at high altitudes. Also found out that large generators won’t run long enough on propane in the winter without extraordinarily large propane tanks. Might fiddle with putting a heat collector on a tank for one of those someday (like a heat sink, only working in reverse), but it’s not a priority.
the cold problem with batteries is definitely a limiting factor with batteries for the next 5-10 years—or until they figure out a solution.
might be why the production plants are in palo alto and not michigan. (but I doubt it.)