Vegetable oil is an ideal fuel but one needs to understand the pros and cons of this approach to compare it to other options, especially biodiesel. Let's start on the upside.
Pro: Widely Available
One of the biggest advantages of vegetable oil is that the fuel is widely available. You can stop and fill up anywhere in North America so long as there's a restaurant that deep-fries its food in vegetable oil. (You'll have to filter the gunk out of the deep-fryer oil first, however.) Not only is the fuel abundant and widely available, so are diesel engine conversion kits. You can purchase them on the Internet.
Like other options, this fuel is renewable and can be picked up for free, for example, from fast-food restaurants whose owners are typically pleased to give it away, rather than pay for disposal!
Pro: Reduces Air Pollution
Vegetable oil burns cleanly and thus helps solve another thorny issue - air pollution from conventional fossil fuels. Like biodiesel, vegetable oil use reduces carbon dioxide emissions. The fuel itself is often called carbon neutral but that's not entirely true. Sure, the amount produced during combustion equals the amount the plants take up during photosynthesis, but remember, it takes energy to make this fuel (gasoline to power a tractor, for instance). The consumption of energy, in turn, produces carbon dioxide. Even so, the fuel is light years ahead of conventional fossil fuels in the greenhouse gas production department.
Pro: Increased Range
Another advantage of vegetable oil is that it dramatically improves the range of a car. Gary Liess of Santa Rosa, California, for instance, can drive his Mercedes more than-get this-800 miles on a tank of diesel (or biodiesel) and a tank of vegetable oil. His partner, with a slightly more fuel-efficient vehicle, can travel 1,000 miles between fill ups, if she wanted, using diesel or biodiesel and vegetable oil.
Con: Cost of Conversion
Like virtually anything we do in life, vegetable oil fuels have some disadvantages. The conversion kits and installation of the kits cost money. Expect to pay $800 to $1,600 for a good kit and installation. In addition, the additional fuel tank takes up a considerable amount of trunk space. And you'll need to still use diesel or find biodiesel to fill the car's main fuel tank.
Con: High Maintenance
You'll also need to find a source of vegetable oil and be willing to collect and store it. Another problem is that the vegetable oil may clog the fuel injectors of a diesel engine over time, according to Sam Anderson of BioFuels Technology, a Denver-based company. For more on this topic, read about how to use vegetable oil as fuel
In addition, you also need to switch the fuel on and off, although back-flush pumps that come with the more expensive kits avoid this task. They automatically purge the fuel lines after the ignition switch is shut off. However, Elsbett, a German manufacturer, now provides a bare-bones conversion kit that allows vehicles to be cold-started on veggie oil (to learn about it go to www.elsbett.com).This system uses only the fuel tank that comes with the car. ....read more