This Car Runs on Veggie Power

By Karen Sauer
As published in The West Roxbury Transcript
Thursday, February 17, 2011

“The use of vegetable oils for engine fuels may seem insignificant today. But such oils may become in course of time as important as petroleum.”

To what forward-thinking person may we attribute this timely statement? Why, to none other than Rudolph Diesel, inventor of the diesel engine. Yes, when Herr Diesel demonstrated his engine at the Paris Exhibition Fair in 1898, it was fueled by peanut oil! Mr. Diesel had a vision of fuel that was grown by farmers rather than pumped out of the ground. Unlike fossil fuels, so-called biofuels are sustainable and renewable.

Unfortunately, after Rudolph Diesel’s death (or rather, his mysterious disappearance) in 1913, the diesel engine was reengineered to run only on petroleum products. But, as they say, “what goes around, comes around,” and today there is a burgeoning movement to convert modern diesel engines to run on biofuels.

An Internet search (type in “greasecars”) turns up various kits to convert a diesel vehicle to burn vegetable oil. But West Roxbury has its own resident expert on the subject, named Mike (last name withheld on request).
Mike, a self-described “inventor and experimenter,” attended one of our WRSE events last year and saw us serving water from gallon jugs. He asked if he could have the empties to store fuel for his car. “It runs on vegetable oil!” When he bought his used 1991 VW Jetta, the body was in good shape but nothing else was, so he converted it to run on vegetable oil about three years ago. The design is Mike’s own, and he installed it with the help of a mechanic friend.

Asked why he undertook this project, Mike responds, “Air quality.” While we often think of diesel engines as polluters (recalling the old busses and trucks spewing black sooty smoke), they run considerably cleaner now, and further, according to the Union of Concerned Scientists: “The use of biodiesel blends in an existing diesel vehicle can reduce the emissions of the tailpipe pollutants associated with conventional diesel including particulate matter (soot) and hydrocarbons.” When asked how his car does at inspection time, Mike replies, “Better!” Nitrous oxide and carbon emissions both went down after he converted to vegetable oil.

Mike adds that his car is very economical to run. How economical? Production costs of most biofuels are very high, but Mike collects his vegetable oil from a restaurant. The restaurant owner, who would otherwise have to pay to dispose of the used oil, thanks Mike for taking it off his hands. Mike reckons that it costs him about three cents per gallon to filter the oil, as opposed to buying fossil fuel oil at the pump for three dollars a gallon.

Mike lets the oil sit, and the particles sink to the bottom (on our planet, gravity is free—why not use it?). He then pours off “the good stuff” and stores it in gallon milk or water jugs. His tank holds 3 ½ gallons, and he carries an additional 4 gallons in the trunk. His Jetta gets 44 MPG, just like a regular diesel engine. But, don’t forget: this is oil that has already been used for cooking; it’s recycled!

One feature that sets Mike’s design apart from the kits that are sold online is that his veggie-oil tank is in the engine compartment rather than in the trunk. That is a big advantage as the fuel must be kept warm (insulation is key), and it’s warmer up front. If the tank is in the trunk, heat from the engine coolant has to be piped back to heat the fuel, which then has to be kept warm on its trip forward to the engine. The car actually has duplicate systems: it starts with fossil fuel and runs on biofuel. So, Mike starts the car, says, “Now it costs three DOLLARS a gallon,” flips a switch, and presto—“Now it costs three CENTS a gallon.”

Mike has refinements in mind for his design and is keeping his eye out for just the right old Mercedes to convert next. Meanwhile, if you encounter a blue Jetta that smells like French fries, please be sure to say hi to Mike!