Biodiesel is a direct diesel replacement. Made from refined vegetable oil, biodiesel is a renewable, domestic, healthy, environmentally safe alternative to fossil fuels. It is biodegradable, non-toxic and non-hazardous. Rudolph Diesel introduced the first diesel engine at the Exhibition Fair in Paris, France in 1898, fueled by peanut oil – the “original biofuel.” The gel temperature of biodiesel is about 30 F, so if you run it in colder weather you can “winterize” by mixing in regular diesel. For example, in Santa Cruz, running a 10% petro diesel (90% bio) blend will winterize the biodiesel. If you live in Tahoe, I would suggest a 50/50 blend. (50% biodiesel, 50% petro diesel)


Over 20 million American vehicles, known as “flex-fuel” vehicles can run on E85 or regular, or any blend of the two. They have a green leaf on the back and use the word “flex”. Also, the gas cap on flex-fuel vehicles is yellow. Technically, all gas cars built since 1985 can run on E50 (50% ethanol, 50% gasoline) but this fuel has not yet been approved. However, there are signs things are slowly changing. We will lobby Sacramento to make E50 “legal” for all consumers. And all gas cars built since 1985 can be fully flex-fuel with an inexpensive kit. Ethanol, aka alcohol was the first fuel of the internal combustion engine in 1830. Gasoline wasn’t invented until 1891. Gasoline was the waste product from refining crude oil into kerosene for lamps.

Renewable Diesel

Renewable diesel (RD) is exactly the same as petroleum diesel but the feedstock is plant based instead of petroleum based. Any diesel can run on renewable diesel with no modification. It is known as a “drop-in” fuel. Like diesel, the gel point is around 0 degrees (F).