sierraclub.org - sierra magazine - march/april 2012 - the next big thing
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THE NEXT BIG THING
In the future, burning plastic will solve all our problems.
iStockphoto/simonox
You may see plastic as an endocrine-disrupting, dioxin-emitting, waterway-clogging, landfill-stuffing, petrochemical problem, but the American Chemistry Council (ACC) has news for you. Plastic, it says, is a green solution to our nation's energy problems. Which would be cool because there's an awful lot of it.
In 2008, Americans sent nearly 29 million tons of plastic to the dump. An ACC-sponsored study conducted by Columbia University's Earth Engineering Center calculates that if we converted all that plastic into energy, we could fuel 6 million cars for one year or power 5.2 million households, even factoring in the energy cost of the conversion. "Plastics have a significantly higher energy value than coal," enthuses the center's associate director, Marco J. Castaldi. "Capturing the energy value of nonrecycled plastics . . . makes good sense because it provides a good domestic form of energy while minimizing impacts on the environment."
It takes about 8 pounds of plastic to produce a gallon of fuel through pyrolysis, a method of cooking plastic into vapor and then condensing the vapor into fuel. A few companies already operate pilot pyrolysis facilities that, they say, could readily be expanded to a commercial scale. Advocates argue that this is a more practical way to deal with plastic waste; unlike recycling, it doesn't necessitate cleaning and separating the different varieties of plastic. And at any rate, only 7 percent of plastic is recycled.
Still, many questions remain about what might be drifting from the smokestack of a pyrolysis plant. While the ACC maintains that plastic-to-fuel technologies produce few emissions, other garbage-to-energy schemes produce plenty. Maryland classifies waste-to-energy as a green technology on par with wind and solar, but a report cited by the Environmental Integrity Project recently found that the state's two trash-burning power plants generate more pollution than its four largest coal-fired plants.
Zero-waste advocates point out the inherent inefficiency in converting oil to plastic and back to oil again, as well as that oil emits carbon dioxide when burned whether it comes directly out of the ground or spends part of its life as a shampoo bottle.
"It sounds like a story that we can spin our garbage into gold," says Roger Diedrich, chair of the Sierra Club's Zero Waste Team. "But it's just that—a story."
—Dashka Slater
Shrinking Arctic Ice