January 22, 2007
French Fry Your Potatoes, Then Fill Up Your Car?
By Michael D. Shaw
The latest salvo from the petrophobes would have us believe that vegetable oil is the answer for energy independence, at least with respect to the transportation sector. After all, it’s no secret that diesel engines can run on vegetable oil, and no less an authority than Rudolf Diesel himself would have agreed. When Diesel presented his engine at the 1900 Paris Exposition, it was running on peanut oil, and his engines would continue to run on vegetable oil, until Big Oil introduced a commercial fuel in the 1920s.
You might have already seen a few cars—all of them formerly conventional diesel-powered sedans— that advertise their use of vegetable oil. If so, you have no doubt also experienced their distinctive odor. If you talk to the owners of these cars, you’ll hear rave reviews: They are pioneers and innovators! But, let’s take a closer look.
This column has long promoted diesel engines, and in late 2005, touted a regional pilot project that involved a community-based collection service for restaurant waste cooking oil, that employed inner city youths to collect and distribute the fuel to institutional accounts. The real success here was a business model based on recycling waste, and cutting into high unemployment, with the Green benefits a nice, but certainly secondary consideration.
At this point, veggie-powered cars cannot be expected to meet the collective needs of America’s drivers, nor will they ever justify the wholesale expense necessary to reconfigure our infrastructure of gas stations and highways.
By the way, don’t confuse straight vegetable oil (SVO) fuel with biodiesel. Biodiesel is oil that has been refined in a chemical process called transesterification that removes the glycerin from the oil. As such, biodiesel is less viscous than vegetable oil and can power any diesel engine with no modifications. It can also be blended with petroleum diesel in any proportions, right in your tank.
But, this article is about vegetable oil cars….
Let’s start with the simple cost of converting a diesel-powered car to one that runs on vegetable oil. This can run upwards of $3,000. Of course, standard gasoline-powered engines need not apply. Then there’s the problem of getting the fuel in the first place. Assuming that you have a nearby source, you would likely have to store your own in 55 gallon drums.
Unfortunately, vegetable oil’s high viscosity and boiling point can cause carbon buildup in your car’s engine, contaminate the lubrication in the crankcase, and wear out fuel pumps and injectors. In short, it can destroy engines.
Because of these troubling facts, the California Air Resources Board and the California Energy Commission either passively ignore or actively argue against vegetable oil as a fuel. Listen to Gary Yowell, an automotive engineer at the California Energy Commission who has explored more than a dozen alternative-fuel options:
“Vegetable oil is not a practical alternative for California. “It would be hellacious on a grand scale. There are about 350,000 diesel vehicles in the state, and assuming a 1 to 3 percent failure rate—and that’s being conservative—the results would be catastrophic.”
Complicating matters further, the generic properties of vegetable oil are not consistent. The source will affect the performance of the car. For example, soy and canola oil seem to be better sources than more hydrogenated oils. Not surprisingly, canola oil is being highly recommended as a source for biodiesel.
In conclusion, vegetable oil is no panacea. It is neither practical nor cheap, and those inclined in this direction would do better to look into biodiesel for their cars. Entrepreneurs, including country legend Willie Nelson and some motivated women from Berkeley, CA have established limited outlets for biodiesel.