Fossil fuels are produced by the decomposition of dead organisms, buried for millions of years. They produce greenhouse gasses and other pollutants, and their continued use could leave mankind as extinct as those decayed fossils. The earth does not hold an infinite amount of these fuels. Barring our extinction, the supply of fossil fuels will eventually run out, though demand for energy never will. An energy source is needed that is both eco-friendly and renewable. In other words, one that doesn’t pollute, and will never run out.