It's a thermal efficiency problem. Yes, you can theoretically turn atmospheric gasses (CO2 and water) into gasoline, but it requires a LOT more energy to create

It's a thermal efficiency problem. Yes, you can theoretically turn atmospheric gasses (CO2 and water) into gasoline, but it requires a LOT more energy to create than you get out of it by burning on the back end. If there's sufficient surplus solar energy one of these days, it's great. Gasoline is just about the perfect energy source for vehicles, but petroleum is kind of a nasty source for gasoline. Unfortunately, it's the only net energy positive one.