That's actually a pretty interesting idea! The commercially available panels with the highest specific power are about 700 W/kg (with an estimated upper bound

That's actually a pretty interesting idea! The commercially available panels with the highest specific power are about 700 W/kg (with an estimated upper bound of 1.2 W/kg) [1], in comparison to gasoline which is 12.5kWh/kg. Solar exposure can be about 5-6 hours of full sun equivalent per day. So the breakeven point would be about two to three days of charging! [1] https://www.osti.gov/pages/servlets/purl/1485564 https://www.osti.gov/pages/servlets/purl/1485564)