Technovations:
From Waste to Watts
The world creates mountains of trash. Here’s how those heaps are being converted into clean, renewable energy.
Dan Saelinger
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E-mailPaul Pabor says he recalls precisely when the University of New Hampshire decided to become the first institution of higher education in the country to get the bulk of its energy from a landfill. Pabor, who is vice president of renewable energy for Waste Management Inc. (WM), says that officials from the school”s Durham campus approached Waste Management in 2005. “The university people were really looking for ways to be more sustainable and use renewable energy,” he explains.
The result: In 2008, UNH agreed to a partnership with Waste Management that has the company supplying the school with enough landfill gas to meet up to 85 percent of its energy needs — a project, the company says, that required the construction of a nearly 13-mile pipeline between a Waste Management-owned landfill in Rochester, N.H., and the campus. According to the university, the benefits of the partnership are both environmental and economic. In fact, the school expects that the program will reduce its greenhouse gas emissions to approximately 67 percent below 2005 levels and 57 percent below 1990 levels. It is also expected to stabilize its annual energy costs, which, the school says, have grown at an annual rate of almost 19 percent during the past five years.
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According to Pabor, Waste Management is building between eight and 10 landfill gas facilities a year across North America, adding to the 100-plus the company already owns and operates. Whether converting landfill gas or garbage to energy, Pabor says, Waste Management has a simple purpose: “Our goal as a company is to pull as much energy out of the waste as we can, regardless of how we do it.”
One of the biggest environmental benefits of converting waste to energy is in the reduction of greenhouse gas emissions, according to companies in that sector. Paul Gilman, chief sustainability officer of Covanta Holding Corp. (CVA), a global developer, owner and operator of infrastructure for the generation of energy from waste, points out that landfills are among the worst offenders when it comes to the production of greenhouse gases. “We can say that for every ton of municipal waste we process, a community is avoiding a ton of carbon dioxide equivalent,” he notes. By his estimate, the 44 energy-from-waste facilities Covanta operates displace around 5 million tons of coal that otherwise would have been burned to create electricity last year, equaling a total carbon offset of more than 20 million tons of carbon dioxide. The company says that its total carbon offset has exceeded 250 million tons of greenhouse gas emissions from 1986 through 2008.
America’s 87 waste-to-energy facilities process about 12 percent of the total waste stream in the country.
In the U.S. and around the world, a host of factors — environmental, economic and government policy — have coalesced to make waste-to-energy generation an increasingly appealing option for power supply and waste management, say waste-management companies. Of the 87 waste-to-energy facilities in the U.S., says Jack Ristau, director of business development of Wheelabrator Technologies Inc., a wholly owned subsidiary of Waste Management, Wheelabrator operates 16. Veolia Environmental Services, a division of Paris-based Veolia Environnement (VE), says it operates two. In total, Ristau says, the 87 facilities in the U.S. process around 90,000 tons of garbage every day, an amount that he says is equal to about 12 percent of the total waste stream in the country. By contrast, Ristau adds, Europe takes about 24 percent of its entire waste stream for use in waste-to-energy facilities.
