Wednesday, February 13, 2008

Peak soil as well as peak oil?

That's just a little snippet from a well reasoned article by George Monbiot, on biofuels. Monbiot argues that many of the crops (and even crop wastes) grown for biofuels actually create a net carbon debt of decades (and even centuries in some cases), and lead to soil exhaustion, not to mention competing with land for food production.

"Removing crop wastes means replacing the nutrients they contain with fertiliser, which causes further greenhouse gas emissions. A recent paper by the Nobel laureate Paul Crutzen suggests that emissions of nitrous oxide (a greenhouse gas 296 times more powerful than CO2) from nitrogen fertilisers wipe out all the carbon savings biofuels produce, even before you take the changes in land use into account. Growing special second generation crops, such as trees or switchgrass, doesn’t solve the problem either: like other energy crops, they displace both food production and carbon emissions."

So just when we were beginning to think that some selected biofuels were the way forward, the counter arguments appear to become more convincing.

"All these convoluted solutions are designed to avoid a simpler one: reducing the consumption of transport fuel. But that requires the use of a different commodity. Global supplies of political courage appear, unfortunately, to have peaked some time ago."

Political courage? Come on George, we haven't see any of that for decades!

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