There’s a limitless supply of natural gas on this planet, and we’re not talking about the gas stored beneath the Earth’s surface. We’re talking about cow manure, which can be refined into natural gas. Although burning natural gas does cause emissions, getting it from gas provides a big advantage as it reduces the need for fracking, the environmentally-destructive practice that extracts gas from the earth. Plus, extracting large quantities of natural gas from cow manure could help replace dirtier fuels like coal and oil.