Environmentally Friendly and Made in the U.S.A.Imagine this: You pull up behind a city bus at a traffic light in your town. As you wait for the light to change, you recognize the familiar sound of a diesel engine and worry that your vehicle is about to be enveloped in a cloud as black smoke is belched from the tailpipe. You can do nothing but hold your breath and wait for the inevitable. When the bus begins to pull away, you are pleasantly surprised that there is no black cloud of exhaust. Then you breathe. You smell the distinct odor of something cooking, yet there are no restaurants in sight. You realize the odor is coming from the bus ahead of you.

No, you're not in the middle of a science-fiction movie. You could be in a number of cities and towns virtually anywhere in the U.S. where biodiesel is being used as an environmentally friendly alternative to petroleum-based diesel fuel in city buses, fire and rescue vehicles, delivery trucks and even passenger vehicles — in short, any vehicle powered by a diesel engine.

Biodiesel is being used in both public and private fleet vehicles because it allows those fleets to be more environmentally friendly and offers a reduction in some emissions without requiring any modifications to the vehicle. And now that it is more readily available in retail locations, an increasing number of individuals who own diesel-powered vehicles are using it, too.

Ted Grozier of Ann Arbor, Mich., has been using biodiesel in his 2002 Volkswagen Golf TDI for over two years. "I read about it on the TDI Club Web site and then did some of my own research," he said. "My car doesn't run any different [on biodiesel] and it feels good to know that it's better for the environment."

What Is Biodiesel?

Biodiesel is an alternative fuel that is biodegradable, burns cleanly and is made from a renewable resource. In the United States, biodiesel is made primarily from soybean oil and secondarily from a product called yellow grease, which is essentially used restaurant cooking oil. It can also be made from tallow, a hard fat that comes from cattle or sheep, which is frequently used to make soap and other products.

In Europe, where there has been a thriving biodiesel industry for about 20 years, the fuel is made from rapeseed oil, a plant that is in the mustard and turnip families. The European variety of rapeseed is not grown in the U.S. because of the climate it needs to thrive, but the canola variety of the plant is grown in some parts of the country. All the same, when it comes to producing biodiesel fuel, soybean crops called feedstock are the best source of biodiesel in the United States.