Biofuel is a term for any liquid fuel not produced from fossil fuels like oil, coal and gas. The most common biofuels are bioethanol and biodiesel, generally used to substitute for, or add, to petrol and diesel.
There are three generations of Biofuels. The first generation biofuels are made from sugars and starches from food crops, vegetable oil or animal fats that could enter the human or animal food chain. These include vegetable oil, biodiesel (a vegetable oil by-product), Ethanol fuel, bioalcohols and biogas.
Second generation biofuels are from non-food crops and include synthetic gas or syngas, fishcer-tropsh diesel, bio-dme, dmf, biomethane, wood diesel, mixed alcohol and biohydrogen diesel.
Third generation biofuels are algae fuel and they do not compete with the food supply, consume CO2 and produce no toxic waste during harvesting. Other third generation biofuels include jathropa, sorghum and bladeswitch grass.