MIKE BLAZEWICZ PHOTO:MATTHEW THORSEN

VERMONT -- Eco-minded motorists running their rigs on vegetable oil are on the move in Vermont. Companies specializing in converting diesel engines to burn waste oil are proliferating. But keeping a fuel supply on hand may require greasing a few palms down the road as competition for free, clean oil heats up. Already, there have been some not-so-eco-friendly exchanges.

Farmer Richard Wiswall of East Montpelier has been tapping area restaurants for their oil to power two 1980s-era Mercedes Benzes, two tractors and seven greenhouses on the 148-acre Cate Farm. He tries to keep the lines of communication open with other grease gatherers, but the fact that most supply relationships are informal agreements leaves the door open for others to step in. "In central Vermont, the supply is tight," Wiswall says. "The people who come on board are looking for oil and tend to go to the sources on the common trail. They unknowingly swipe oil from people who've been getting it for a couple of years... We put a sign saying, 'Oil saved for Cate Farm.' Most people respect that, but some people swipe it anyway."

Karen Pearson, co-owner of the Easy Street Café & Restaurant in Waitsfield, a hotbed of veggie-oil vehicles, likes supporting the alternative energy effort. But she also knows how competitive the quest for free fuel has become. So, from the day Easy Street started serving customers, she has exclusively saved the oil from two 5-gallon Fryolators that run in the kitchen through breakfast, lunch and dinner for one collector. She included the anonymous recipient in discussions early on. "We said to him, 'What exactly do you need?'" she says, "and he gave us a little education on that" -- primarily in terms of oil quality. The result, she adds, is a win-win-win for her, the collector and customers.

It's hard to believe restaurateurs like Pearson once paid to have their waste oil taken away. Now, when it piles up out back, tempting other oil-car drivers in the Mad River, "We get phone calls asking about it, and we say that we do have someone to take it," she says. If the oil goes uncollected for a few weeks, she gives her collector a call. "It's like stealth," she says. "He just drives in and puts it in his truck, and then I see him in here for lunch."

That level of cooperation between suppliers and consumers may hold the key to the near-term success of the veggie-powered auto revolution, says Mike Blazewicz. The Burlington-based river restoration and ecological design consultant runs a '91 Volkswagen Jetta on vegetable oil he collects from two sources -- one is Maynard's Snack Bar in Moretown, the other he prefers not to disclose. Blazewicz, who also teaches courses on fuel-tank conversion at Yestermorrow Design/Build School in Warren, hasn't had problems with people clipping his "cubies" -- the cube-shaped cartons that restaurant-quantity vegetable oil comes in. But he sees another potential conflict intensifying on the supply front. "The higher quality the oil, the less problems you're going to have in your engine," he says. "It's becoming less common to find restaurants that are purchasing high-quality oil. There's plenty of oil out there, but a lot of it is either partially hydrogenated or fully hydrogenated. Or the restaurant owners and cooks don't care for it in a way that's going to be useful to us."

Blazewicz isn't complaining, though, and knows the relationship between suppliers and consumers is a two-way street requiring that oil collectors not take their suppliers for granted. "I think it's important for people who are taking vegetable oil from restaurant owners to be mindful, to be responsible in that pickup," he says, "so as to keep that relationship a positive one."

Liz Fukushima, an acupuncturist and Chinese herbal medicine practitioner in Burlington, avoids the supply problem by running her '02 Volkswagen Golf on retail vegetable oil. After converting her fuel tank to burn vegetable oil last spring, she pays about $2.83 per gallon for over-the-counter soybean oil. With diesel fuel at the pump going for roughly $3.10 at press time, Fukushima doesn't save much money by going greasy, but she enjoys making a smaller environmental footprint through reduced toxic emissions. Still, she's on the hunt for a street-level source to help her recycle while commuting. "I have a couple of leads that I won't disclose," she says. "The ideal thing in the waste-veggie-oil world is to find a place that produces at the rate that you want it . . . If you can find the local guy who's dumping 5 gallons in the dumpster, and keep that out of the loop, that's really cool."

In a capitalist marketplace, these supply-and-demand dynamics point to inevitable conclusions for vegetable oil vehicles. "It's a matter of time before people are going to be paying for vegetable oil," Wiswall says. "As diesel fuel keeps going up, vegetable oil becomes more valuable." His advice for would-be greasecar jockeys: Find a steady fuel supply before making the move to vegetable-powered locomotion.