Petroleum has been used as transportation fuel for more than last 100 years. But it is not fulfilling the need of increasing population. LPG, CNG, Diesel are also used as Fuel. Most promising replacement come from organic biomass crops such as Corn, Rapeseed, Sugarcane, Palm oil, Jatropha, Soybean, Cottonseed, Sunflower , Wheat and Switch grass (Panicum virgatum). Biofuels are better than fossil fuels because :

1. Biofuels are renewable. 2. They lower toxic emission. 3. They burn cleaner. 4. No need to import them . 5. They can be grown locally and produced locally. Ethanol is produced from plants and mingled with petroleum diesel and gasoline. Green fuel, biofuel is distilled from plants and animals. It is env. Friendly and Sugarcane, corn put through fermentation to create ethanol. Oil producing plants Vegetable oil can be used as fossil oil to create diesel that can be burn by vehicle. One more fungus Botryococcus braunii which store more fat (tree fungus ) can also provide green fuel. The organism found in Patagonia rain forest produce a mixture of chemicals that Is similar to diesel . The fungus Gliocladium roseum grow inside ulmo tree (Eucryphia cordifolia) North Patagonia produce large amount of long chain hydrocarbon similar to fossil fuel. Green algaes can also produce biofuels.1 acreof algae can produce 200 times as much oil as 1 acre corn.Thus biofuel can be produced by green plants which is renewable and clean. Comparative account of biofuel plants and fossil fuels are studied in the present paper with special reference to Rajasthan INDIA.

Keywords: Biofuels, Green plants, Fossil fuels, Algae, Fungus.