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Biodiesel and ethanol can replace or supplement diesel and gas

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Biofuels are renewable energy sources made from biomass (plant matter such as trees, grasses, agricultural crops or other biological material) that can be used for our transportation and other fuel needs. The two most common types of biofuels are ethanol and biodiesel.

• Ethanol is an alcohol made by fermenting any biomass high in carbohydrates such as corn, sugar cane, wheat or barley. It is the same type of alcohol found in beer and wine. Ethanol is commonly used as a fuel additive to reduce carbon monoxide emissions from vehicles.
   

• Biodiesel is made by combining alcohol (usually methanol) with vegetable oil, animal fat or recycled cooking greases. It can be used as an additive to reduce vehicle emissions (typically 20%) or in its pure form as a renewable alternative fuel for diesel engines. Diesel Engines can typically run on biodiesel with little or no modification to the engine or the fuel system. 

Source: National Renewable Energy Laboratory http://www.nrel.gov/vehiclesandfuels/npbf/

What types of vehicles can run on biofuels?

Diesel Engines can typically run on biodiesel with little or no modification to the engine or the fuel system. It can be used in its pure form (called B100) or as a blend with diesel fuel at any ratio. Biodiesel provides similar horsepower and fuel economy as petroleum diesel. Some problems may occur during cold weather because biodiesel thickens more than diesel fuel.

• Examples of 2006 Diesel Vehicles: Volkswagen Beetle, Golf, Jetta, Mercedes-Benz E320 Cdi, Jeep Liberty/Cherokee 4WD

Flexible Fuel Vehicles (FFV) can run on conventional gasoline, ethanol or a combination of the two. Most FFVs use E85, a mixture of 85 percent ethanol and 15 percent gasoline. Many federal, state, and local government vehicles, as well as light-duty vehicles, buses, and trucks currently run on ethanol. Examples of FFVs include some models of the Ford Taurus, Chevy Tahoe and Dodge Stratus.

• Examples of 2006 Flexible Fueled Vehicles: Chevrolet Impala, Chrysler Sebring, Dodge Stratus, Ford Taurus, GMC K1500 Sierra, Dodge Ram 1500 Pickup

Source: http://www.fueleconomy.gov/feg/byfueltype.htm

What are the environmental benefits of biofuels?

Biodiesel

• Pure biodiesel reduces carbon dioxide emissions by more than 75% over petroleum diesel.

• A 20% blend of biodiesel reduces carbon dioxide emissions by 15%.

• Produces fewer particulate matter, carbon monoxide and sulfur dioxide emissions.

• Biodiesel is much less combustible than petroleum diesel (flash point greater than 150°C, compared to 77°C).

Ethanol

• Most ethanol-fueled vehicles produce lower carbon monoxide and carbon dioxide emissions and the same or lower levels of hydrocarbon and non-methane hydrocarbon emissions.

• Oxides of nitrogen (NOx) emissions are about the same for ethanol and gasoline vehicles. E85 has fewer highly volatile components than gasoline and so has fewer evaporative emissions.

Source: U.S. Department of Energy: http://www.eere.energy.gov/afdc/altfuel/altfuels.html

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