Is Sustainable Trash-Burning a Load of Rubbish?

Some experts say it lets us get away with producing more and more garbage.

Municipal solid waste (aka garbage) being burned in an incinerator; this incinerator can handle 17 tons of trash an hour. Ole Poulsen, public domain

Paul Gilman wants your trash.

Gilman isn't a hoarder, and he maintains an admirable standard of personal cleanliness. But when he passes the dumpsters linked up at the end of driveways on trash day, filled with unwanted garbage to be taken to a landfill, all he sees is waste. To Gilman, chief sustainability officer at Covanta Energy, garbage represents an untapped and surprisingly clean source of energy.

The world is drowning in garbage. Between squalid dumps outside of slums, landfills tucked away into economically disadvantaged neighborhoods, and the tons of plastic endlessly circulating in the ocean, our trash is polluting every last nook and cranny of the planet. At the same time, humanity is using up the world’s fossil fuels at an ever faster clip, throwing tons of carbon dioxide into the atmosphere and depleting reserves of oil and coal. Gilman and advocates of waste-to-energy approaches believe that they can solve both problems simultaneously.

Covanta is one of the world’s biggest companies specializing in waste-to-energy, essentially burning garbage at high temperatures to produce steam and create electricity. Rid your mind of the incinerators of old, Gilman emphasizes. These are no pollution-heavy behemoths belching toxins into the air. Scrubbers remove chemicals like dioxins and furans, and less garbage in landfills means less methane in the atmosphere. It also means fewer carbon dioxide emissions from burning fossil fuels.

“This gives us the ability to produce electricity from garbage with fewer emissions than from making electricity from coal,” Gilman says.

Many agree with Gilman and Covanta. Dubai is currently building a waste-to-energy plant valued at $2 billion, and cities around the world are joining in. The U.S. is currently home to 84 waste-to-energy plants, and more are being built, promising a dual solution to both our energy and our trash problem.

Not everyone is buying it. Monica Wilson, program manager at the Global Alliance for Incinerator Alternatives, says these claims are, well, rubbish. “I think they’re wrong,” she says. “They’re turning one problem into a host of others,” such as air pollution and a continual reliance on disposable products.

Humans aren’t actually addressing the source of the problem, Wilson says. Only by reducing waste and increasing recycling and composting will we ever be able to manage our garbage issues.

Burning trash is one of humanity’s oldest approaches to garbage, along with flinging unwanted materials aside. When humans were relatively scarce and didn’t produce much trash, these options did the trick. New York City’s solution was to dump its waste into the ocean, which worked well until everything washed back up on shore. Although the city stopped dumping its solid waste in the 1870s, it would continue dumping sewage sludge into the ocean for more than 100 years.

Enter the incinerator. The simple act of lighting a match seemed to give cities around the world the answer to their garbage problem.

Covanta believed that it could use the power of the incinerator to not only address the growing piles of trash being generated each year, but also help create electricity, too. By altering the amount of garbage in the fire and how much oxygen it received, waste-to-energy companies like Covanta were able to increase the efficiency of the burn, generating more energy with less waste. To comply with EPA standards, they worked to clean up emissions, with a special eye towards dioxins, a class of potently toxic chemicals such as those found in Agent Orange that build up in fat cells over a person’s life.

Nicholas Themelis, an emeritus professor of environmental sciences at Columbia University, has spent his career studying waste management, and he believes that the process offers humans some of the best options to date for dealing with trash that can’t be recycled. Each year, humans around the world send enough garbage to dumps to fill a 38-square-mile landfill, roughly the size of metropolitan Paris.

“Landfilling is an unconscionable use of land. And why waste energy?” Themelis says.

GAIA's Wilson has a more straightforward approach to dealing with trash: Stop making it in the first place. Burning toxic garbage doesn’t magically eliminate it. “All you’re doing is converting waste from solid garbage to air pollution. You’re just creating a landfill in the sky, and allowing companies to burn the evidence of how much toxic stuff they’re creating,” Wilson says.

Whereas Gilman ticked off statistics demonstrating the safety of waste-to-energy, Wilson had just as many facts claiming the opposite. If these plants produced so few dioxins, why did the new facility being built outside Toronto have to be closed down 13 times during the testing phase for emitting over the accepted amount? She also cited the 2013 closure of the waste-to-energy plant in Dumfries, Scotland, also for dioxin emissions.

Peter Orris, a physician at the University of Illinois at Chicago, has spent his life studying preventive medicine, especially related to environmental exposures. Some of his first days as a physician were spent caring for Vietnam veterans who had been exposed to Agent Orange, and he finds any possibility of increasing a person’s dioxin exposure concerning.

“It’s not just dioxins. It’s also trace metals and particulate matter. All of it is harmful,” Orris says.

Incinerators are also hungry machines. The high temperatures at which they burn require a lot of trash to keep the fire going, creating an ever-expanding market for trash. The more people throw away, the more money companies like Covanta make, Wilson says, because municipalities typically pay them per ton of trash. Therein lies the problem: Even if incineration was a clean way to produce energy, it’s not the best way to deal with trash because it doesn’t discourage the production of garbage in the first place.  

Researchers and advocates on both sides of the debate have cited Europe as the future of waste management. To Gilman and Themelis, Europe is a model because it has greatly reduced landfill usage both by increasing recycling and composting, as well as turning to waste-to-energy plants. Wilson and Orris say that it’s the increasing movement towards creating a zero waste culture that is Europe’s true leadership. Orris believes that economic pressures can help push our society closer to this ideal by requiring companies to pay for the entire lifecycle of their products, including later disposal and incentivizing reusable options.

“We need to prevent problems, not cope with them,” Orris says. “Waste-to-energy sounds great, but it’s still combustion. It probably wasn’t a good idea 20 years ago, and it’s not a good idea now.”

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