Tuesday, February 12, 2008

Not so Green Biofuels

Before you get too excited about ethanol or biodiesel (or even those corn pellets for your furnace) consider two new research reports published recently by Science Magazine.  The papers demonstrate that, when when all factors are considered, biofuels may actually contribute more greenhouse gases than conventional fuels.  The crux of the new research (apparently missing from earlier analyses) is the global land-use patterns behind the production of biofuels.

While fuels such a palm oil may be carbon-neutral (or better) on their face, the picture changes considerably if rain forests have been destroyed to make room for those palm trees.  The destruction of this habitat is a double whammy -- not only are large amounts of greenhouse gases released when the rainforest is burned, but the tremendous ability of these areas to soak-up carbon is lost, too.  Even when existing cropland is used to produce biofuels, the studies show that invariably new habitat is cleared to make-up for the lost food production.  

The take-home message from the reports seems to be that while biofuels hold lots of promise, we're better off growing the source crops in marginal habitat or, better yet, focusing on production from crop by-product and waste sources.

There's been a lot of press about the new research.  Here are links to recent stories in the New York Times and NPR.

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