BERKELEY, Calif.  It is a classic road rally, 600 miles from the liberal embrace of Berkeley to the anything-goes lights of Las Vegas. No speeding is allowed, or in some cases even possible. And if you stop to refuel, it had better be in someone’s trash.

On Saturday, five teams began the Escape From Berkeley, maybe the world’s most eco-friendly motor race, driving all manner of alternative-fuel-burning jalopies, roadsters, and even a frying oil-fueled Mercedes-Benz, with a single goal: to complete the race using no petroleum.

“Gentlemen, start your whatever they are,” the M.C. shouted to begin the race, which offers the winner $5,000.

The final catch of the race is that participants  artists, environmentalists and even a cattle farmer from Alabama  have to find or scavenge their go-go juice, whether it is used vegetable oil from restaurants or twigs and sticks from the side of the road. All the vehicles, which had to be street legal, were allowed to start with a single gallon of whatever fuel they used.