Gold and crafted from aerospace-grade aluminum, the 800-millimeter (31-inch) Olympic torch for the 2012 London Games weighs a mere 800 grams (1.8 pounds), making it the lightest ever. The hope was that the British-designed and engineered torch also would break precedent as the first to be lit with carbon-neutral fuel, but that was not to be.
Olympics sponsor EDF Energy vowed back in 2007 that it would develop a green torch fuel made from miscanthus, or elephant grass. But EDF was never able to deliver on the biofuel.
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So for the relay across the United Kingdom by 8,000 torchbearers that started 70 days ahead of the games, the Olympic flame was lit by the same fuel that has been in use since the 2000 games, a mix of propane and butane.
Shaun McCarthy, chairman of the Commission for a Sustainable London 2012, was not pleased. "The excuse of 'We ran out of time' is not acceptable," he said.
The amount of carbon dioxide (CO2) released by the relatively clean-burning fuels is minute, he admitted, but if a carbon-neutral fuel had been used, "the power of the message across the globe would have been highly significant."
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Still, there have been worse torch fuels in Olympics past. For the 1996 Atlanta games, the organizers used propylene, which burned brightly, but released copious carbon and smoke. Perhaps the biggest torch debacle was in the 1956 games in Melbourne, Australia, where a fuel mix of magnesium and aluminum emitted large clumps of burning debris as the torch entered the stadium. Now, that's entertainment!
As for EDF Energy, which boasts it is the largest low-carbon electricity provider in the United Kingdom (thanks to a technology that would be an unsuitable torch fuel-nuclear power), it is metering energy use at the games. Viewers can watch the kilowatt-hours in real time online at http://www.edfpowerthegameslive.com/
(Measure your own carbon footprint with the Personal Energy Meter)