vanI remember when real environmentalists drove smoking VW vans with bumper stickers that said stuff like, “You can’t call yourself an environmentalist if you eat meat.” They didn’t get the best gas mileage, but hey, you could do worse. They were replaced by the forest-green Subaru Outback (Eddy Bower edition if you were really cool), seen by the dozens in any REI parking lot. These are presently being eclipsed by the ubiquitous Prius. But, there is stiff competition from the diesel Jetta replete with biodiesel stickers all over the butt end.

As we all know by now, biodiesel can be made out of a lot of things:

Soybeans: 50 gallons per acre
Rapeseed: 150 gallons per acre
Jatropha: 175 gallons per acre
Palm oil: 650 gallons per acre

To limit the impact on the planet, maybe we should start pressuring our biodiesel distributors to sell fuel made only from palm oil? According to the World Wildlife Fund, we would also need to demand that it be made out of palm oil grown only on degraded, non-forested land:

Jakarta, Indonesia – Plans to create the world’s largest palm oil plantation in Kalimantan along Indonesia’s mountainous border with Malaysia could have a devastating impact on the forests, wildlife, and indigenous people of Borneo, warns WWF. The proposed scheme, funded by China, is expected to cover an area of 1.8 million hectares (equivalent to about half the size of The Netherlands). Most of this mountainous region, part of the “Heart of Borneo,” still holds huge tracts of forests, where threatened species such as orangutans and the Borneo bay cat live, and 14 out of the island’s 20 major rivers originate from. According to WWF, new species have been discovered there at a rate of three per month over the last ten years making the area one of the richest on the globe in terms of biodiversity.

Go here for a really good soybean vs. palm oil debate. Unfortunately for President Bush and any soybean farmers who voted for him, you can’t grow palm oil in the Midwest.

Forgive me my sins, but once again, I have been having impure thoughts. I jumped on the net and took an ecological footprint test, obtaining a score of 12. I took it a second time, putting zeros in for transportation issues. My score dropped to 11, indicating that I use an acre or two a year for my transportation needs.

Now, for the sake of discussion let’s say I just bought a new diesel Jetta for the express purpose of burning biodiesel. Since it takes about 10 acres of soybeans to produce a year’s worth of biodiesel for the average American, I would have to add 10 acres to my score, making it 21 (a 90% increase). I have never been particularly enamored of footprint tests, but it is undeniable that if you run on pure biodiesel made from soybeans you will be directly commandeering 10 fertile acres of the planet for your own personal use. These numbers imply that driving a car that runs on biodiesel made from soybeans is worse (from an ecological-footprint-test point of view) than driving a Hummer. Like I said, I don’t care for these tests, but there is food for thought here.

As an aside, I pointed all this out to my next door neighbor a few weeks ago — who, by the way, had just ordered a new diesel Jetta. It now has two biodiesel stickers on it. Man, talk about putting your foot in your mouth (sorry about that, neighbor).

I would fully expect most Jetta owners out there reading this work of blasphemy to rationalize (third definition) away my arguments, not that they would need to. I am not picking on Jettas per se. They are good quality, well-engineered, well-built, high-mileage cars with or without biodiesel. They are also one of the most popular cars in Europe.

The average American consumes about 28 pounds of food per week. We also consume about 69 pounds of (11 gallons at 6.25 pounds per gallon) of automobile fuel per week. One reason for being a vegetarian is to lower one’s ecological footprint. There is something self-defeating about being a vegetarian and driving a car that uses soybean-derived biodiesel. My car would consume more soybeans than your average cow.

About 26% of our CO2 emissions come from transportation. If a quarter of the cars in America converted to biodiesel in the next decade, we could cut our CO2 emissions by 6%. Which sounds OK until you realize that if a quarter of U.S. drivers today used biodiesel made from soybeans, there would be absolutely no farmland left in North America, unless of course we bought our soybean oil from someplace else, like South America.

500 gal per year / 50 gal per acre = 10 acres

470,000,000 arable acres in US / 10 acres per car =47,000,000 cars.

47,000,000 cars can use biodiesel made from soybeans / 200,000,000 cars in US = 0.25 or 25% (a quarter of all cars in the US).

You can find support for any crazy idea on the internet. Fortunately for me, there is at least one other skeptic out there — George Monbiot. His biggest concern is that biodiesel will raise food prices. There is plenty of food in the world today. The 800 million who go to bed hungry every night do so because they cannot afford it. Taking an optimistic view, one answer to that might be to get them out of poverty by employing them inside the huge vegetable oil industries (undoubtedly owned by the likes of BP, Shell, and Exxon) that will spring up to make biodiesel.

Three-quarters of our CO2 comes from sources other than our cars. Biodiesel, regardless of what you make it out of, can’t fix that. So what is the answer then?

Uh, I have misplaced my crystal ball, but clearly it isn’t making biodiesel out of soybeans.

Engineering compromises; you cannot escape them. Biodiesel is renewable and carbon neutral but consumes the surface of the planet. Cuba, short of fossil fuels, spends most of its resources staying fed using extensive organic farming. Picture Cuba also trying to grow enough biomass to give every Cuban two tons of biodiesel annually (69 pounds per week x 56 weeks per year).

Running diesel engines on vegetable oil is old technology, first demonstrated over a century ago. Most of our energy needs used to come from burning biomass in our fireplaces and steam engines. When we started running out of biomass, we began burning coal and finally oil. Biodiesel is basically a return to square one, burning biomass.

There is a perfect storm brewing here: Rising oil prices, Bush, the red-state soybean farmers, a movement for oil independence to protect us from terrorists, and worst of all, the profit motive have created a movement aligned with environmentalists in praising biodiesel. In our collective euphoria, we are ignoring the negative ramifications of making it out of the wrong stuff. I did not see any money in the energy bill to fund research on salt-water algae farms. Unfortunately, salt water algae farming is about as far along as sub-critical fission and clean coal.

Replacing the fossil fuels in the cars and trucks of the world with biodiesel has the potential to convert much of what remains of the Congo and Amazon into vegetable-oil plantations (be it palm oil or soybean or whatever). We need to do better than that. Preserving our biodiversity is more important than driving our cars. If we are going to do it, we have to do it right, sparing our biodiversity and keeping hunger at bay while we are at it.

I am counting on you biodiesel enthusiasts out there to come up with some thoughts as to what we should be making biodiesel out of and why — hopefully something a little more productive than the “Poorly researched, poorly written. So bad, in fact, it could go directly to the “troll” file. Shame on you Grist!” kind of stuff.