Center for Advanced BioEnergy Research, University of Illinois at Urbana-Champaign

Wednesday, September 8, 2010

Ethanol's mid-life crisis

The Economist
Sep 2nd 2010 Piracicaba, SÃO PAULO STATE

The sugar industry produces food, fuel and environmental benefits. How fast it grows may depend on an argument about how it should be regulated

IT IS what passes for a winter’s day in upstate São Paulo. The sun is blazing from a blue sky feathered lightly with cirrus cloud. In a large, sloping field overlooking the city of Piracicaba, a mechanical harvester chomps through a stand of three-metre-high sugar cane, fat and juicy from months of sunshine. The harvester slices the cane into 20cm chunks and regurgitates them into a 30-tonne trailer moving alongside that will lug them a few kilometres to the Costa Pinto mill (pictured). There the cane is weighed, washed, tipped onto a conveyor belt, crushed and then, depending on market conditions, crystallised into sugar or distilled into ethanol. The woody residue—the bagaço—is burned in two high-pressure boilers that, according to the flickering needle in the control room, are supplying around 50 megawatts (MW) of electricity to the local grid—enough to power half of Piracicaba.

Sugar has been grown in Brazil for 500 years, and the country is by far the world’s biggest exporter of it. But sugar now also forms the nucleus of a new agro-industrial and renewable-energy complex. Biofuels, mainly derived from sugar, are Brazil’s most important source of energy after oil. For a unit of energy, the production and use of sugar-based ethanol generates only two-fifths of the carbon emissions of petrol, and half those of corn-based ethanol, according to the United States Environmental Protection Agency. And bioplastics made from sugar cane are poised to move from the laboratory to the corner store, with the launch of soft-drink bottles.

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