Mowers fueled by fry grease

By Emily Senger

Chowing down on a vat of used french-fry grease could be an adventure in cardiac failure, but makes a healthy choice for diesel-powered equipment and the environment on the University of Calgary grounds.

The U of C launched a one-year biodiesel pilot project last summer, and now runs all of its diesel equipment on a mixture of refined canola oil and standard diesel fuel. Results have been positive, with smoother-running machinery and 68 tonnes of carbon dioxide prevented from reaching the atmosphere.

“The machinery probably runs better,” said U of C grounds mechanic Harry Friesen. “In one case where the engine needed a tune up, after we started using biodiesel it cleaned it up. [Biodiesel] actually cleans carbon off the equipment.”

The biodiesel project started in spring 2005 with a trial fleet of four ride-on lawnmowers. Two ran only on biodiesel fuel and two on a mixture of 50 per cent biodiesel and 50 per cent regular diesel.

The only problem with the 100 per cent biodiesel mowers was the odour permeating campus air–much like that found downwind of Peter’s Drive-In.

“It smells like cooking oil, some say like french fries,” said Friesen. “It’s strong–like you were next to a deep fryer.”

After the initial run, all diesel equipment on campus was switched over to the current mix of 20 per cent biodiesel and 80 per cent diesel. All mowers, larger tractors and dump trucks now run on the 20:80 mix, which is better for Canadian winters, since pure biodiesel freezes.

The biodiesel is created by mixing a natural fat–either canola oil or tallow–with alcohol and a catalyst, usually methanol and potassium hydroxide, respectively.

The original oil is a triglyceride molecule, but when the mixture is heated the denser glycerol molecules break off of the triglyceride and sink. The biodiesel then rises to the top and can be skimmed off, washed and used for fuel.

Biodiesel is slightly more expensive than standard diesel. The 20:80 mix used by the university costs about 99 cents per litre, according to Patrick Luft, president of Veggie Velocity, the supplier for the U of C.

Luft added the price should drop to be comparable with straight diesel if the Alberta government follows the lead of both Manitoba and Saskatchewan and lifts provincial taxes on bio-fuel.

The slightly higher price-tag also comes with an environmental guarantee, according to Luft.

“Emission-wise it’s a carbon-neutral product,” he said. “We use canola oil or tallow and either of those products are from cows or plants, rather than other fuels which release new carbon into the atmosphere.”

Though the environmentally-friendly fuel is just catching on in Canada, other countries are way ahead.

“Europe is extremely advanced in the use of biodiesel,” said Luft. “You can actually buy it at the pump.”

Luft said environmentally-conscious consumers shouldn’t expect biodiesel to hit the pumps in oil-rich Calgary any time soon. At present, the only commercial plants in the province are still in the planning phase, including Luft’s Veggie Velocity plant near Airdrie, which should be completed by July 2007.

Service station pumps would also need to be adjusted, said Luft.

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