File this one under: Bursting Our Bubble. A wonder biofuel, Canola oil made from rapeseed, which had been promoted as a great alternative to corn because of its oily energy content, is wonderful at least one thing: creating greenhouse gases that cause global warming. It's being grown all over Europe, and American agronomists had been scaling up test plots in hopes of jump starting a U.S. biofuel industry based on the little yellow weed.
The idea has always been that deriving fuel from vegetable oils -- which is what the diesel engine was originally designed to burn -- would result in at least a zero-sum game when it comes to global warming. Sure, burning anything releases carbon, but growing the next crop will absorb carbon back from the atmosphere. Industrial farming techniques used to grow rapeseed and other common biofuels, and the process to make it into fuel, create a whopping four times as much global warming pollution as old, dirty petroleum diesel.
That's according to Nobel prize winning chemist Paul J. Crutzen, whose study was written about by Reuters. The main culprit here is fertilizer which -- surprise! -- is often derived from petroleum. Over-use of fertilizer has already been implicated in a number of other problems, including the ever-expanding dead zones in coastal zones, where fertilizer breeds oxygen-depleting blooms of algae. In this case, its the off-gassing of nitrous oxide, a potent greenhouse gas, that makes fertilizer problematic. Corn had already been blackballed as an ethanol source because it has relatively little energy output for the energy needed to grow it.
The corn planting blitz this year -- resulting in the most acreage planted in decades -- has been blamed for a variety of problems, from increased prices in a range of foods, to a record big Gulf of Mexico dead zone. Questions have also been raised about the ability of existing -- or even maximum potential -- farmland to yield enough crop to both fuel our vehicles and feed our population. Corn, too, and sugar cane, had unfavorable ratios according to the Nobel winner's analysis.
All hope is not lost, though. Woody plants like poplars, willow and switchgrass require relatively little nitrogen to grow, so they should be the crops scientists focus their energy on when developing new fuels. The difficulty with those plants has been, largely, that the cellulose they form is harder to break down than in rapeseed, corn or sugar cane -- the most common crops used today to make biofuel.
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