An Australian explorer and TV host has gone where no American has gone before: Driving 16,000 miles around the United States on two dozen vehicles powered not by fossil fuel but by alternative energy -- from solar power to cow pies.
Shaun Murphy crossed San Francisco's Golden Gate Bridge last Friday after having driven, ridden, flown and canoed his way without stopping at a gas or diesel station.
"The cool thing is most of the fuel we've used is being produced today on American farms," Murphy said in marking his journey's end. "I never paid a cent for fuel but I've had to barter for it. Along the way I've milked a few cows, caught a few fish and washed a few dishes in return for fuel."
Murphy's "eco-trek" took him from San Francisco to the Canadian border, across the Rockies to the Great Lakes, on to New York, south to Florida, then across the South and back to San Francisco.
Trip ends in Hummer limo
The fuel included wind and solar power, but also cow pies, garbage, crawfish, corn whiskey and cooking oil.
Video: Among the 28 vehicles he used were an electric motorcycle, a pickup truck powered by soybean oil and a jet turbine, a solar-powered canoe, and a plane powered by corn whiskey, or ethanol as farmers like to call it.
Murphy even capped off the trip, which took nine months and covered 30 states, in style: by driving a 32-foot H1 Hummer limo powered by a potpourri of energy sources.
Team engineer and limo owner Russel Gehrke says Murphy wanted to "incorporate every fuel he used when he started."
Ethanol and soybean oil, also known as biodiesel, were burned in the engine, while solid organic matter was mixed with ethanol in a blender and then poured into a "gasifier" where hydrocarbon gases were captured to help fuel the vehicle.
The solid matter included dog food, beans, stale cookies and left over sandwiches.
Fuel smoothie used
The gasifier, Gehrke says, "allows the biodiesel to last longer," increasing the mileage to 12-15 miles per gallon while maintaining a top speed of 75 mph.
"Think of it as a supplement," he says of the fuel smoothie. "Five or six pounds of it go into a tank, and it only comes into play on the highway when temperatures go up."
In addition, heat from the exhaust is used to power the gasifier, creating what Gehrke calls a "closed loop" system.
Ten solar panels atop the limo's roof make electricity, which charges the battery pack and helps power a system that produces hydrogen. The hydrogen is added to the engine to reduce emissions and improve performance.
Beignets and crawfish
Earlier in the trip, Murphy drove an H2 Hummer with a similar system. "We fed the Hummer beignets in New Orleans, then crawfish, Pop Tarts, and leftover Cajun food. We added soybean oil to power us all the way across Louisiana to Texas," said Murphy.
In an online log, Murphy wrote that the goal with the Hummer was "to turn the biggest gas guzzler on the road into a cool-fuel vehicle purring along without gas or diesel."
The H2 also had its own gasifier. "We mixed dog food with old cookies and baked beans, along with some corn whiskey and pumped it through to the engine," Murphy wrote. "We now have a 3 mile to the gallon gas guzzler steamin' along at around 12-15 mpg."
Having worked in Australian television, Murphy took along a crew to film his trip and hopes to sell his adventure to a cable network.
Murphy has logged stories, photos and video of his journey online at www.ecotrekker.com.
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