Straight Vegetable Oil

"Do you want to push it?" 33-year-old Kathy NiKeefe asks from the driver's seat of her 2001 VW Golf TDi. I lift my hand toward a button on the dash labeled "veggie switch" in cut-out letters. Once the button is pressed, the car's engine switches from diesel to used vegetable oil stored in an extra tank in the trunk. NiKeefe, a Santa Fe, New Mexico-based political activist, spent the weekend enrolled in a class, converting her car's engine for this purpose. It's a process that involves rerouting fuel lines and wiring a dashboard switch, but can be done at home by anyone with some mechanical savvy, diesel engine knowledge, and tech support.

The veggie switch allows the converted diesel engine to run on straight vegetable oil.

We are cruising down New Mexico's Old Las Vegas Highway, a frontage road that runs along I-25. I add pressure to the switch, expecting a Chitty Chitty Bang Bang moment where the car lurches, coughs, and then transforms. "Nothing happened," I say, somewhat disappointed. "Exactly!" she says, laughing. We are still traveling at 50mph, whizzing past piñon and juniper shrubs. The only difference is that now the engine's power source comes from a six-gallon tank filled with used fryer oil from a dumpster behind a Japanese restaurant—obtained for the bargain price of free.

Straight vegetable oil, known as SVO, can power any diesel engine. Unlike fossil fuels, SVO is renewable— made by recycling waste oil destined for stock-feed, lipstick, or a landfill. With a few modifications to diesel vehicles (namely adding a separate fuel tank and extra fuel lines), you can run a car on vegetable oil with only a five percent loss of fuel economy. Start the engine on petro-diesel or biodiesel and let it warm up for three minutes, then flip the veggie switch, and off you go.

Charles Anderson, 30, the proprietor of a small Missouri business called Greasel, educates the public on the fuel potential of vegetable oil and sells diesel engine conversion kits. Anderson describes himself by declaring what he is not: "I'm not a stark-raving tree hugger or a farming Republican with a beer belly. I'm just inherently cheap and love things that are out of the ordinary."

Throughout 2003, Anderson conducted SVO tests in Japan, which showed that the fuel released almost no nitrous oxide or carbon dioxide emissions. This preliminary research is positive news in terms of stalling the greenhouse effect and reversing ozone-depletion. Also noteworthy: According to the EPA, running a car on vegetable oil cuts sulfur dioxide emissions, a primary cause of acid rain, by at least 50 percent.

A major incentive for making the switch to SVO is cost—the fuel is available free-of-charge from almost any local restaurant, most of which pay waste management companies to dispose of old fryer oil and are happy to have veggie-mobile owners haul it away. Anderson says Japanese restaurants are bar-none the best sources of SVO because they dispose of cooking oil regularly and their fryers are some of the cleanest in the restaurant business.

According to Anderson, there are currently over 1,000 cars fueled by veggie oil on the highways of the U.S., mostly in Central California. While this number is negligible compared with the 213 million passenger vehicles in the counrtry, it’s a good start.

Want to find out more? Check out our green fuel guide:

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