Burning Buried Sunshine

I’ve been meaning to share this great study from Jeffrey Dukes at the University of Utah which we discuss in the sustainability masters programme at BTH. The info’s a couple of years old now but after chatting with the sceptical flatmate recently and many others in the past, it seems to be something that really hits home to people about the significance of our fossil fuel use. Here’s the media report from The Guardian summing up the findings:

The Heavy cost of a litre of oil petrol

Thursday November 6, 2003

If you burned a litre of petrol on the way to work, consider this: it took 23.5 tonnes of ancient, buried plants to produce. That's the equivalent of 16,200 square metres of wheat, roots and stalks included. So says new research that aims to raise awareness about the need to change our energy-consumption habits.

The long, slow process that converts plant matter into oil is very inefficient, says ecologist Jeff Dukes of the Carnegie Institution of Washington, Stanford, who did the calculations. Less than one part in 10,000 of the organic matter becomes oil.

"So much carbon is lost back to the atmosphere through decomposition, it's only the residues that are turned into fossil fuels," says Dukes. Writing in the journal Climatic Change, he warns that less than a tenth of the carbon in plants buried in peat bogs was turned into coal. In 1997, he points out, we burned fossil fuels equivalent to more than 400 times the amount of plant matter produced on Earth in the same year.

I think this is really quite profound! Imagine! What we burned as fossil fuels in 1997 took the equivalent of 400 years of the world’s total plant growth to produce! And, to repeat it, 1 litre of petrol = 23.5 tonnes of plant matter, compressed over millions of years! No wonder we’ve achieved so much in the industrial age with such a powerful and seductive energy source. Of course, we know it aint gonna last forever. We know the side effects of uncontrolled fossil fuel use are catastrophic in terms of greenhouse gases and other pollutants. And, we know there are alternatives.

Dukes, J.S. 2003. Burning buried sunshine: human consumption of ancient solar energy. Climatic Change, 61(1-2): 31-44. Article in pdf.