Chicago Tribune

EASTHAMPTON, Mass. – From the rear of an abandoned rubber factory, under the shadow of Mount Tom, Justin Carven says he has figured out a way for Americans to save money on gas, curb air pollution and reduce their dependence on foreign oil.

A tousled 28-year-old in a mechanic’s shirt and wire-rimmed glasses, Carven is the inventor of the Greasecar Vegetable Fuel Systems, a $795 kit that is fitted under the hoods of diesel cars and trucks and allows them to run on used vegetable oil.

Once a vehicle is transformed into a Greasecar, every McDonald’s, Dunkin’ Donuts and neighborhood Chinese restaurant becomes a potential fuel stop.

The idea of running a vehicle on fryer fat is so simple, so amusing really, that it is often dismissed as little more than a novelty for the Birkenstock crowd, an idea that is perhaps reinforced by the company logo: “Drive Vegetarian.” The much larger biodiesel industry dismisses Greasecars as experimental and unreliable.

But in the last year, as gasoline and diesel fuel prices roared past $2 a gallon, orders at Carven’s Greasecar shop have soared, and now he and his staff are hoping to position the Greasecar as a more mainstream product.

Already, a number of trucking firms have expressed interest in outfitting their fleets with the conversion kits, though so far they’ve only committed to pilot programs.

“We went from sales of 100 a year to more than 100 a month,” Carven said. To date, he has sold about 1,200 kits.

Greasecar’s success has come at a time of growing interest in such alternative fuels as biodiesel, which is made with vegetable oil that has been chemically processed and is typically blended with regular diesel fuel. Ethanol, by contrast, is a grain-based additive made for gasoline engines.

Recently, President Bush stopped in Virginia to tout the virtues of biodiesel as an alternative fuel source, and starting this summer Minnesota will become the first state to require that diesel fuel include some biodiesel.

Joe Jobe, executive director of the National Biodiesel Board, sniffed at the Greasecar concept, saying that straight vegetable oil can ruin a car over time because glycerin – which is removed in the chemical process that makes biodiesel – gums up the engine.

“It’s the National Biodiesel Board’s position that we don’t advocate the use of straight vegetable oil as a fuel other than for experimental purposes,” he said. “Glycerin is a bad actor in a diesel engine and over time will cause problems.”

Carven doesn’t dispute that there’s a track record of vegetable oil damaging diesel engines, but he said early biodiesel experiments had problems too. He pointed out that the early problems with vegetable oil were important to developing more reliable Greasecar technology.

“We have never experienced clogging of injection systems or the like,” said Lee Briante, part of the Greasecar team in Easthampton. “We have over a million road miles, on over 1,000 vehicles, to disprove their brush-offs.”

The idea of using vegetable oil to power engines didn’t originate with Carven. In fact, he is quick to note that Rudolph Diesel – who invented the diesel engine in the 1890s – ran his famous engine on peanut oil.

Carven invented his first Greasecar kit while he was a student at nearby Hampshire College, after a friend told him about using vegetable oils to run generators in Africa; he launched his company in 2001.

Greasecar kits only work on existing diesel cars and trucks, and they don’t replace the diesel gasoline tank or engine. Rather, the Greasecar kit becomes a secondary fuel source, with a 15-gallon grease tank tucked into the trunk.

While many owners install their own kits, there are a half dozen Greasecar-certified mechanics.

Carven said any type of vegetable oil can be used to power a Greasecar, as long as its filtered, and most restaurants are glad to give it away, since they normally have to pay to dispose of it.

Grease from Asian restaurants tends to be best, he said, because they often use pure canola or soy oil – without hydrogenated oils – so it is easier to collect and filter.

One quirk of driving a Greasecar is that the exhaust tends to smell like whatever was cooked in the grease, whether French fries, tempura or fish fillets. The smell is less noticeable in newer cars with catalytic converters, Carven said.

“It’s kind of like smelling a barbecue two houses away,” he said.