In 1912, Rudolf Diesel said, "The use of plant oil as fuel may seem insignificant today. But such products can in time become just as important as kerosene and those coal-tar products of today." In 2007, are we just now on the verge of realizing Diesel's vision? It is all over the news; Italy and Brazil are ready to scale up production, tax breaks for biodiesel are being discussed in nearly every U.S. state legislature, and President Bush has been looking into biofuels as a potential alternative to foreign oil. Cummins recently announced its support for using up to 20% mixes of biodiesel. The fringe fuel is finally getting some mainstream attention.

Biodiesel is a fuel grade product made from crops, designed specifically to be used in diesel engines. Many people confuse it with used fryer grease, or waste vegetable oil (WVO.) WVO is another story altogether, requiring filtering, separate fuel tanks, and other modifications to be used without clogging or damaging the automobile's fuel system. Fuel grade biodiesel can be used in most modern diesels without any modifications, and actually has a higher cetane rating than its petroleum-based counterpart. And it isn't coincidence that vegetable oils can be used effectively as a fuel for diesel engines. Many people are surprised to hear that the original Diesel engine was never designed to run on a petroleum product, but peanut oil. Modern biodiesel is made from a number of crops grown by domestic farmers including soybeans, corn and even algae. The fuel is a truly renewable resource, it biodegrades similarly to sugar if spilled. It produces fewer harmful emissions than petroleum-based fuels, is less harmful to the ozone layer, and its overall lifecycle has a favorable effect on CO2 levels and global warming. Is that green enough for you? Eat that you gasoline burning, nickel-batteried hybrids!

Here's the best news; I can say from firsthand experience that Hummer H1's love the stuff. Those with a keen eye may have spotted the stickers on my truck before... yes, I have really been running a mix of biodiesel and petroleum diesel for years in my own Hummer. The truck has really run great on it - I would go so far as to say it runs smoother, and it definitely produces a cleaner smelling exhaust, which is a real plus in a convertible diesel truck. That's right, my truck is proof that you can run your gargantuan 4x4 on this clean natural stuff, and it will still scale rocks and haul loads with torque to spare.

So what are the downsides? First, the cost and availability vary depending on where you live. I have to pay almost a dollar more per gallon for the soy stuff in my area, and it is still fully taxed by the state as a transportation fuel. Until recently I also had to drive 40 minutes away to find it. Another downside is that in very cold weather, biodiesel does not respond as well to the additives that prevent the fuel from gelling. For that reason, I run a regular winter-mix diesel with performance additives in the cold season, and then go back to running the biodiesel/petroleum mix for the rest of the year. Lastly, you will want to check with the manufacturer to make sure you do not void any current warranties by running a high mix of biodiesel. Most manufacturers allow for a mix of 2-5% biodiesel, though some are raising that number. When in doubt, check with the manufacturer.

If (or more accurately, when) biodiesel becomes more affordable and more readily available in my area, I will happily run 100% biofuel for 3/4 of the year. Demand seems to be creeping up, so it is natural to assume that the prices will drop somewhat and the availability will rise. Manufacturers will likely be announcing more and more warranty acceptance for use of higher level mixes of biodiesel. The future is now, Rudolf - it just took us nearly 100 years to get here. So go save the planet by filling up your H1 with biodiesel before your next wheeling trip!

For more information on biodiesel, visit http://www.biodiesel.org.