What happens if your are taking a trip, and WHOOPS! The battery runs out of charge? I think the Solar only recharges and that is probably too slow to be of much value to limp to a charging station. What car was it that you opened up an emergency gallon or so Gas tank? My guess is we start getting major Warnings when you have a guesstimated 50 miles remaining. Possibly, the software and GPS could also consider, 50 miles left but no charging station closer than a hundred. Is the answer, "call a tow truck"?