Steve Hochstetler was fed up with buying gasoline.  It wasn’t so much the price of gasoline that was bothering him, but the realization that the vast amounts of money and effort going into the petroleum business benefitted the few at the expense of many.  “Nigeria is a perfect example.  The money doesn’t flow down to the people of Nigeria.”  In his work for IBM, Steve had travelled to 32 countries, seeing firsthand how people could be desperately poor in countries rich in resources.  While living in North Carolina, Steve had been heavily involved in the fair trade organization Ten Thousand Villages, which provides artisans in developing countries an international market for their products.  So when he and his wife Pat moved to Austin in 2000, they spearheaded the drive to open a successful Ten Thousand Villages outlet on South Congress.  They no longer manage the store, but making a difference in the world remained very important to both the Hochstetlers, so they turned their attention to a new project.

When Steve realized that buying gasoline was not helping anybody, at least not helping anybody who needed help, he decided to stop using it.  He traded his Toyota Prius for a 1983 diesel Mercedes 300TD wagon with 186,000 miles on it.  He enrolled in a workshop to learn how to convert waste vegetable oil into biodiesel.  He bought a biodiesel processor from a guy on craigslist who had built one out of an old electric water heater.  But as he learned to make biodiesel, Steve discovered that the conversion process required both methanol and lye, toxic chemicals that he just didn’t want in his garage.  So he ditched the idea of making his own biodiesel and decided to run his car on straight, unconverted, waste vegetable oil.

Now you can’t just pour canola oil into your Mercedes and expect to motor on down the road.  First, you need the right kind of waste oil:  liquid, fairly clean, and with almost no chicken fat in it.

During the sacrificial season of Lent, Catholic churches have a lot of fried fish suppers.  To me a fish fry doesn’t really seem like much of a sacrifice, but anyway, after the parishioners go back to eating meat, the churches end up with a lot of excess vegetable oil.  Steve takes it off their hands, collecting 700 or 800 gallons of lightly used oil at the end of every Lent season, enough to fuel his Mercedes for the rest of the year.

The oil has to be filtered really well or food particles will clog up the engine.  Steve is compulsive about this step because he wants to keep driving.  He pours the oil through a series of filters from 600 to 200 microns.  The openings in the mesh are barely wider than a human hair.  Then he lets the oil sit undisturbed in a barrel for several weeks, so any remaining tiny particles settle to the bottom.  For the final step he pours the oil through a one micron filter, fine enough to remove bacteria.

The filtered oil is very, very clean, but it still can’t be put directly into the diesel engine.  Vegetable oil is a big, complex molecule, and more viscous than biodiesel.  Chemically, vegetable oil is composed of three hydrocarbon chains (fatty acids) connected to a glycerol molecule.    Biodiesel is made from vegetable oil too, but biodiesel has the glycerol stripped off during processing, leaving hydrocarbon chains which are almost identical to diesel made from petroleum.

In order to use the thicker vegetable oil in an automobile, it has to be made less viscous so it won’t gunk up the engine.  Just like butter turns liquid in the frying pan, vegetable oil gets less viscous when it is heated.  Cars that have been converted to run on vegetable oil have two tanks.  They start on biodiesel, and then after a few minutes when the engine and the fuel are good and hot, they switch over to the oil.  Before turning the car off, it is switched back to biodiesel to flush the system, so that the vegetable oil won’t cool off and turn to Crisco in the fuel injectors.  Some people say that the exhaust smells like French fries when it’s running on oil, but Steve claims he doesn’t notice it.

Steve and Pat have put about 50,000 vegetable oil miles on the Mercedes wagon without any problems with the engine, and they have also acquired and converted two more Mercedes sedans to run on waste oil.  When they need more biodiesel for start-up and cool-down, Steve gets it at DieselGreen Fuels, Austin’s only source of biodiesel.  They will give him 30 gallons of biodiesel in exchange for 120 gallons of his fish fry oil.

Though he is keeping his day job at IBM, Steve plans to start a side business called “GreaseMyMercedes” to help other people convert their own diesel cars to waste oil.  He admits that a few cars running on vegetable oil won’t replace the gasoline industry, but it’s a small step that he can make toward alternative fuels.  “At least I’m doing something,” he says hopefully.  “If everybody just did a little something, the world would be a lot better place.”