Unlike other renewable energy sources, biomass can be converted directly into liquid fuels for our transportation needs. The two most common bio-fuels are ethanol and bio-diesel.
Ethanol is made by fermenting any biomass high in carbohydrates, like corn, through a process similar to brewing beer. It is mostly used as a fuel additive to cut down on a vehicle's carbon monoxide, and other smog causing, emissions.
Biodiesel refers to a vegetable oil- or animal fat-based diesel fuel consisting of long-chain alkyl (methyl, propyl or ethyl) esters. Biodiesel is typically made by chemically reacting lipids (e.g., vegetable oil, animal fat (tallow)) with an alcohol.


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