They can accurately claim that their vehicles smell as sweet because they run their diesel engines on recycled vegetable oil, taken from doughnut shops, greasy spoons, Chinese restaurants and the like.
"It smells a lot better," he said.
But the smell is only secondary. Biodiesel, as it's called, is much better for the environment than fossil fuels, according the the U.S. Department of Energy. Its emissions are less harmful, and it's made from recycled oil that would otherwise be thrown away.
Unfortunately, the biodiesel can be expensive, costing over $2 a gallon from one of the few distributors that sell it. So Mr. Powell helped organize a class on Sunday to teach people how to make their own, for about 42 cents a gallon. And visitors showed up at the Community Environmental Council building from as far as Los Angeles.
Get Oil Out! Inc. was also a sponsor, and Common Vision of Santa Cruz, a group that travels in a bus to teach communities how to make their own biodiesel, led the class.
The oil is heated to 110 degrees, mixed with a type of alcohol called methanol and a small amount of lye. Then it is filtered to remove any food particles. The fuel works on a regular diesel engine, without any overhauls, though engines older than 1993 might require new seals in their fuel pumps.
Mr. Powell is creating a cooperative called BioBrothers, with four members so far, to buy and make the "biodiesel" fuel together. The group plans to collect the used french fry grease and other vegetable oil from local restaurants for free. The remaining ingredients will push the cost of the fuel up to about 45 cents a gallon.
"It's just the easiest thing in the world," said Paul Wright, a BioBrother who drives a 1983 Mercedes diesel.
"There's no reason to go halfway around the world or the next town for that matter to get fuel."
In addition, the U.S. Department of Energy published a paper in 2000 saying that it was working with manufacturers of biodiesel to lower the commercial cost to under a dollar by 2005.
People can substitute regular diesel or use a blend of biodiesel and regular diesel if they run out of the treated vegetable oil. Biodiesel can be used in boats or buses, wherever regular diesel is used -- except in extremely cold temperatures. Biodiesel thickens more than regular diesel in the cold and requires special systems in places like Montana or Massachusetts in the winter. Biodiesel reduces fuel economy by 10 percent.
]"We have finite resources. Oil will run out. Will we be ready?" said Paul Wright. "My family will be."