Alternative Fuels
There are several types of alternative fuels available today, and many more are still in the research and development stages. Right now the main alternative fuels that you may find at gas stations are E85 and biodiesel. They are the two most promising types of alternative fuels since both can reduce our dependence on oil, lower greenhouse-gas emissions, and be produced domestically from a number of different natural sources. Ethanol, the base of E85, is also biodegradable and does not contaminate water.
E85 is 85 percent ethanol and 15 percent petroleum fuel. Ethanol is produced from corn and other natural crops and it burns cleaner than gasoline, producing fewer greenhouse-gas emissions. Right now there are not any commercially created vehicles that run entirely on ethanol. FlexFuel vehicles are designed to operate on ethanol blends such as E85 or on regular gasoline. One drawback to E85 is that it reduces fuel economy by about 20 to 30 percent, which means that a car will travel fewer miles on a tank of E85 than on a regular tank of gas.
In the 1800s Henry Ford designed a car that ran only on ethanol. In 1908 he designed a Model T that operated on either ethanol or gasoline. During World War II, the United States used ethanol when gas was in short supply. However, gasoline was both inexpensive and readily available in the postwar era, so ethanol faded from thought.
Biodiesel is a natural fuel derived from vegetable oils and animal fats. It can be made from soybean oil, canola oil, sunflower oil, and recycled cooking oils. Biodiesel produces fewer air pollutants than regular petroleum-based fuel. Biodiesel is the most thoroughly tested of all alternative fuels and shows a lot of promise. It performs as well as regular diesel while emitting little to no greenhouse gases, and it can be used in vehicles that run on regular diesel without the need for any special equipment or conversions. Homemade biodiesels are not registered by the EPA and may violate vehicle warranties. Vehicles do need modification to operate on homemade biodiesel.
Dr. Rudolph Diesel intended the diesel engine to be able to run on a variety of fuels. When he demonstrated it at the 1900 World Exhibition in Paris, it was fueled by peanut oil. Diesel engines were used in ships and railway locomotives in the early twentieth century, but it was not until 1936 that Mercedes-Benz introduced them in passenger cars.
Natural gas and propane are current alternative fuels, but they are fossil fuels, though they both generate less air pollution and greenhouse gases than regular gasoline. Other biofuels are currently being developed; woody crops are being converted into butanol and oily crops such as jatropha show promise for diesel.
