The show tested the hypothesis that a car with a carburetor type gasoline engine can run on hydrogen gas alone, which was confirmed as viable, although the high cost of hydrogen gas as well as storage difficulties currently prohibit widespread adoption. They also tested a device that supposedly produces sufficient hydrogen to power a car by electrolysis (running an electric current through water to split its molecules into hydrogen and oxygen). Although some hydrogen was produced, the amount was minuscule compared to the quantity necessary to run a car for even a few seconds.