[Hydrogen] Thirsty? Imagine bending down to your car tailpipe and taking a big slurp. Hydrogen-powered vehicles could make that possible (though you’d probably prefer to get your drinking water elsewhere). Unlike gasoline-driven combustion engines, the hydrogen fuel cell generates power not by burning, but through a chemical reaction in which hydrogen and oxygen are converted into energy with water as the only byproduct. It’s not just clean, as a fuel source, hydrogen offers nearly three times the energy of gasoline since it burns hotter and faster.