To be sure, waste vegetable oil is not the solution for our energy crisis. It is a small part of the solution, and I hope the government invests in waste vegetable oil recycling along with all of the other promising alternative energy technologies--blue-green algae biodiesel, mycodiesel, lithium-ion batteries, wind power, solar cell technology--rather than throwing huge amounts of money at the corn lobby (ethanol) or continuing to do business as usual without carefully considering our dependence on non-renewable sources of energy.
The only mechanical problem we encountered on our cross-country trek was our fault: used veggie oil that wasn’t filtered well enough. Because of this, we had to replace fuel filters that clogged more quickly than normal (about five unplanned stops in all). Apart from these setbacks, the Benz started right up, using its diesel purge tank, at temperatures well below freezing on the bitterest of mornings. It climbed above 6,000 feet in a beautiful snowfall in the Guadalupe Mountains outside of Carlsbad, New Mexico (we left it idling while descending 75 stories below the earth into Carlsbad Caverns, for fear the veggie oil would congeal and leave us stranded if we shut the car down). It cruised comfortably at 75 mph without breaking a sweat, hauling luggage and occupants and 90 gallons of extra fuel.
Rudolf Diesel won the the grand prize at the World's Fair, Paris, in 1900 for his engine that ran on peanut oil. He intended his invention for vegetable oil--not petroleum--and envisioned that it would be a boon to local agrarian economies and energy independence. It was pretty cool to be able to rekindle Diesel's intent, albeit with a few modern twists in our cross-country trip.--Colin Mathews
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