Waste Management Milwaukee

Garbage power

Three turbines generate electricity from gas produced from surrounding landfills. Waste Management is adding a fourth turbine that will begin producing electricity in June.

Germantown — The gas given off by rotting garbage is suddenly chic.

As interest in renewable fuels grows in the United States, old banana peels, rotten meat and moldy fruit are decomposing in landfills in a process that creates combustible gas used to generate electricity, heat buildings and power vehicles.

To be sure, there isn't enough landfill gas to satisfy the nation's or even the state's energy demands, but its use is increasing as the fuel solidifies its place in the growing kaleidoscope of alternative energy sources.

In metro Milwaukee, Waste Management Inc. is expanding electricity-generating capacity, adding a fourth landfill gas-powered turbine to its power plant in Germantown. The newest turbine is scheduled to begin producing electricity in early June.

The gas is collected from the company's landfill sites in Germantown and Menomonee Falls. Once all four turbines are operating, they will provide enough electricity to power about 10, 000 households, Waste Management says.

"People don't realize that you can power 10, 000 homes with what we're doing here, " said Dale Stark, Waste Management's power plant manager at the Germantown site.

Nationwide, the number of landfill gas projects has grown to 510, up from 136 in 1995, the first year for which the Environmental Protection Agency began compiling such data. The projects generate more than 12 billion kilowatt-hours of electricity per year and deliver about 100 billion cubic feet of landfill gas to end users or pipelines per year.

"There's been an increased amount of interest over the last number of years to recover landfill gas, not only because of its energy value but (because of) concerns over climate change and the impact of methane, which is a fairly strong greenhouse gas, " said Jeremy O'Brien, director of applied research for the Solid Waste Association of North America.

"There's a landfill in Ohio that's actually recovering it for use as an automotive fuel, " O'Brien added.

Power for 50, 000

In Wisconsin, landfill gas generated 388, 958 megawatt hours of electricity in 2008, the most recent year for which the state Public Service Commission has data. This would have powered 50, 000 homes, the PSC says. The electricity generated represents about 1% of the state's total.

"You're recovering energy. It's that simple, " O'Leary said. "It saves generating it somewhere else."