Alternative fuels include biomass, natural gas, and electricity. Biomass includes plants, trees, and animals that can be converted into fuels like ethanol, methanol, and biodiesel. Ethanol is produced from biomass in a four step process: photosynthesis, biomass harvesting, fermentation, and processing. Methanol is typically made from natural gas or coal but can also be made from biomass. Biodiesel is made from vegetable oils, animal fats, algae, or used cooking grease.