It's no secret to the majority of our readers that it is possible to run many older diesel engines on nothing more than straight vegetable oil. In fact, the first diesel engine, invented by Rudolph Diesel, ran on peanut oil. This fact is also well known by the students at the Michigan Technical Academy
who have converted their own school buses to run on waste vegetable oil. Garden Fresh Foods in Ferndale, Michigan is providing used veggie oil that was first used to fry tortilla chips for no charge. The total cost of the fuel for the two buses that are running on 100-percent veggie oil is estimated at about 80-cents a gallon. Other buses are running on a 10-percent blend of oil and diesel fuel. As the temps in Michigan go down, the blend will be adjusted, though the students are currently hard at work solving that problem with heaters. Great work.
[Source: The Detroit News