For fuel-cell vehicles, hydrogen replaces gasoline as the substance that keeps the engine running. But where do you fill up such a tank?
Honda's solution is this home hydrogen station, a setup designed for your driveway that can turn eight hours of sunlight into 0.5 kilograms of hydrogen, or about enough for 30 to 35 miles of driving. It wouldn't be enough for a road trip, but could be enough to allow you to commute without paying for gas.
Of course, if and when hydrogen fuel-cell vehicles catch on, there will be hydrogen stations around like we have gas stations now. But I've never seen a solar panel pump out free gasoline, have you?