The list of possible alternative fuel sources is long and growing. It's so far included biomass (corn, wood, various food crops), algae, micro-organisms, and other flora and fauna. The latest possibility: cow urine. According to MSNBC, pee-powered cars, homes, and personal electronics could be available within six months!
The challenge with hydrogen-based fuels has been threefold: production, storage, and transportation. Pee solves the production issue: one of the major component of urine is urea, which contains four atoms of hydrogen bonded to two atoms of nitrogen per molecule. Stick a special nickel electrode into a container of the stuff, apply an electrical current, and hydrogen gas is released. And it turns out that animals, from cows to people, can also handle storage and transportation within reason.
According to the article, a car that runs on a pee-powered battery could get about 90 miles to the gallon. (We assume that's gallon of urine, though they didn't specify.) Urine from one cow, the developing scientists postulate, could heat 19 homes!
The possibilities (as well as the jokes) are endless. The first available systems will likely be large-scale, designed for farms that capture animal waste. But in the not too distant future, you could be taking a controlled leak into a refillable battery to power your GPS, headlamp, and camera. Let's hope that scientists perfect the seals on those things before they hit mass market!