More than $250,000 a year – for years – had been going up in flames at the Ada County landfill.
But for the past two years, the county has been turning trash into cash and into enough electricity to power a small town.
“It is a win-win-win situation,” said Fred Tilman, Ada County Commission chairman.
Federal requirements and safety concerns require the county to get rid of its landfill-produced gas – a mostly methane and carbon dioxide byproduct of decomposing solid waste.
But instead of burning it off, as it used to do, the county has tapped it as a renewable energy source. And because a private company is converting the gas into electricity, it costs the county nothing to run the system, Tilman said, and the county’s share of the profits keeps increasing.
FROM NUISANCE TO RESOURCE
Landfills and livestock are the two largest human-related sources of methane in the U.S., according to the Environmental Protection Agency. Each accounts for about 23 percent of all human-related methane emissions.
If it is not captured, landfill methane becomes a greenhouse gas at least 20 times more potent than carbon dioxide, the principal greenhouse gas.
Uncaptured landfill gas also poses a threat because it can contaminate groundwater or even explode.
Because of the danger to safety and health, municipal landfills are required to capture and destroy the harmful gas. In Ada County, the gas was collected and burned off in a flare.
When Tilman first became a commissioner, one of his first official duties was to go to the landfill and cut the ribbon on the two big flares that burn off landfill gas.
“I was so amazed standing there when they fired those things up. As I watched millions of BTUs going up in the air I thought, what a waste. That is what prompted me to say ‘We’ve got to be able to figure out how to do something with that,’ ” Tilman said.
$600,000 IN REVENUE AND COUNTING
In late 2006, the county partnered with Georgia company G2 Energy LLC, which purchased and installed two engines at the landfill to convert the gas into electricity.
Earlier this year, G2 was purchased by Fortistar, which owns more than 50 landfill power plants across the U.S. and represents about 12 percent of the landfill gas-to-energy market.
The company sells the energy to Idaho Power, according to Dave Neal, director of Ada County’s solid waste management department. Each engine generates about 1.6 megawatts of electricity – enough to power 2,400 average homes.