A Pennsylvania landfill is generating enough methane gas to power the entire community, and company officials said that's a win-win example of turning garbage into renewable energy. But some environmental groups believe such assumptions are mistaken.
Waste Management operates a landfill for Tullytown Borough in Pennsylvania, and it now sends enough gas to a power plant to supply electricity for the entire town, which counted 1,872 residents last year.
The methane is generated by the decomposition of waste, and contained in the landfill by a liner and the tons of trash, said Bob Iuliucci, Waste Management's senior district manager. But instead of letting the gas just leak out of the landfill, the company installed a system to collect the gas and route it to a pipeline.
The gas is sold to a generating plant, where it's burned to create steam, which produces electricity.
Iuliucci said it's a good thing for the community and the company.
The U.S. Environmental Protection Agency agrees. It has operated a cooperative program since 1994 to help companies collect the landfill methane, citing reduced local air pollution, the generation of renewable energy, and the fact that the projects destroy methane, which is considered to be a contributor to global warming since it is 20 times more effective at trapping heat in the atmosphere than carbon dioxide.
According to the EPA, municipal solid waste landfills are the third-largest source of human-related methane emissions in the United States, accounting for about 17 percent of these emissions in 2009.
The methane project does help the town, though indirectly, Tullytown Borough manager Carmen Raddi said in an email.
"The methane gas program is a simple process and an obvious use of the situation and a sign of the thought and planning that went into the landfill. While Tullytown receives no direct benefit financially from the methane production the more profitable the landfill the more both the County and the Borough can negotiate in the way of host fees and benefits for the Borough and ultimately the residents," he said.
Iuliucci said residents can't believe the trash they put out comes back as electricity.
"When they learn about the energy, they're just in awe," he said.
But some environmental groups said the "conventional wisdom" that led the EPA to push for collection of landfill methane is mistaken.
The Sierra Club opposes landfill gas programs. A report by the group said it appears the relatively small CO2 reduction that might be achieved by replacing fossil fuel with landfill gas is outweighed by landfill practices that seek to boost methane production.
The Sierra Club believes the better solution is to sort organic materials such as lawn cuttings and household garbage, and compost them instead to mixing them into the landfill.
Bruce Hamilton, deputy executive director for the Sierra Club, said that in the beginning that group thought the landfill gas process was a good idea, too. But after studying the issue, the supposed benefits just didn't add up.
"For people to think that just, gee, it's there, it's safe -- it's not working out that way," he said. "We just want to discourage people from thinking this is a great solution to our energy problems."
But the EPA said in a statement that landfill gas energy helps to reduce odors and prevent local methane emissions.
The landfill gas "is a small but important component of an integrated approach to solid waste management, given that the use of landfills continues to remain the predominant method of waste disposal in the United States," the EPA said.
EPA said the landfill gas doesn't compete with other solid waste disposal alternatives, nor does it encourage the growth of landfills.
Waste Management said it now operates 129 landfill gas programs across the country, which provide fuel to power half-a-million homes.