Our Green Streets Blog

There’s nothing like the holidays for putting the issue of  post consumer waste front and center.  And this raises a question:  wouldn’t it be great if we could take some of that waste and turn it into a valuable resource instead?  That’s the idea behind biodiesel–to take old, worn out frier grease and transform it into an environmentally friendly fuel for our cars and trucks.

The NICEST biodiesel home brew facility I've seen.

Biodiesel is produced through a process called “Transesterfication,” in which fats such as restaurant greases, animal fats, vegetable oils, and even oil from algae are reacted with an alcohol, such as ethanol or methanol.  This reaction causes the liquid to separate into glycerin (about 10 percent of the starting volume) and biodiesel (about 90 percent of the starting volume).  The glycerin can be used to make soap, and the biodiesel can be blended with petroleum diesel and used in any compression-ignition (diesel) engine. The most common of these blends in the United States is “B20″ which is an 80-20 biodiesel-petroleum diesel blend.

With modification, engines can burn 100 percent biodiesel, known as “B100.”  These modifications are sometimes, but not always necessary to avoid maintenance and performance problems.

A shower head for "drying" (de-watering) the biodiesel

What’s more, this is not a “new” or “emerging” technology, but actually has its roots in the 1930s, when Henry Ford and George Washington Carver worked together to develop alternative energies.  They wanted to apply agricultural products to the growing industrial markets such as plastic and rubber.  Carver and Ford saw that petroleum depletion was inevitable, and they saw great potential for crops like soy to provide an alternative to petroleum.  In fact, Dr. Rudolph Diesel, the German scientist who invented the compression-ignition (aka diesel) engine, ran his very first engine on peanut oil.

In January 2001, the U.S. Department of Agriculture launched a program providing cost incentives for the production of 36 million gallons of biodiesel.  Since then, more than a dozen states have passed favorable biodiesel legislation, and a bill that would set a renewable standard for fuel in the United States, and another that would give biodiesel a partial fuel excise tax exemption were introduces to the U.S. Congress in 2003.

Today, biodiesel been tested well in excess of 50 million miles in every type of diesel engine. There are over 500 commercial fleets in the United States that currently operate on various blends of biodiesel, including all four major branches of the military, the federal government, and multiple municipal fleets.

Some Biodiesel Facts: