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US Landfills Convert Trash into Clean Energy Source

Millions of people throw their trash away and forget about it. But this is just the beginning of a process that could haunt our planet. Garbage in a landfill decomposes and emits methane gas for 30 years or more. The accumulation of waste is increasing the amount of methane gas.

"Methane is the second-most important greenhouse gas after carbon dioxide and is responsible for about 15 to 17 percent of the warming of the atmosphere that has occurred over the last 150 years," says Dina Kruger, director of Climate Change at the U.S. Environmental Protection Agency, also known as the EPA.

Now the EPA is embarked on a five-year, $53 million project to promote the use of methane gas. Brown Station Landfill, in Prince George's County is an active participant. It's located near Washington D.C. The open section of the landfill is taking up to 2,500 tons of trash per day.

"This is our drill: we place the waste, we push it up, we compacted it and we cover it with soil," says Darryl Flick, head of the Prince George's Waste Management Division. "All these black lines show you all the horizontal piping associated with gathering this gas. Each one of the dots is a well or a trap."

There are now 160 gas wells. For more than a decade, a closed off section of the landfill has been producing about 100,000 cubic meters of gas per day. After methane gas is drawn out of the landfill it is placed in a pipeline and sent to the generator facility. "This is a classic landfill gas well” he says, “All this power is being produced by landfill gas."

This facility exports methane gas to be processed in other places, and sells 3.8 megawatts of power to the utility company. NASA's Goddard Space Flight Center in Greenbelt, Maryland is the main recipient of methane gas from another Maryland landfill.

Energy manager Berry Green describes the process, "The gas comes from the Sandy Hill landfill about 5 miles away. It comes under ground in a 10-inch pipe and then it pipes it to the power plant here. It comes above ground and goes to two of our five boilers inside the power plant and from there we use that gas to heat water to make steam and we send that steam through an underground network that heats about 31 buildings."

According to the EPA another 350 landfills across the U.S. are participating in the program. And within the next few weeks, 15 countries will join the efforts to recover and use methane gas. Experts estimate that within a few years the environmental and economic benefits could be more than tripled.