by Ryan Stanton

06-02-08 Get a whiff of this: Methane gas from landfills actually can be harnessed as a source of renewable energy. It's not a new technology, but it's an idea that's been gaining popularity since the 1980s. Now it's catching on in a big way as waste companies search for so-called "greener" ways to do business and utilities look to boost their alternative energy portfolios.
"It's going to change things within our lifetime for sure," said Tom Horton, a spokesman for Waste Management, operator of 275 landfills nationwide. "I think it's really going to be remarkable when you dial ahead to the year 2020 and see where we're getting our power from."

Landfill gas is the natural by-product of the decomposition of solid waste and is comprised primarily of methane and carbon dioxide. Since 1994, the US Environmental Protection Agency has had a federal program to promote the reuse of landfill gas as renewable energy. Preventing emissions of powerful greenhouse gasses into the atmosphere helpsprotect the environment, according to the EPA.
"Whether you agree with the theories about global warming, the idea that we're going to move to more sustainable energy sources is a great thing," Horton asserted.

Horton's firm oversees the People's Landfill in Saginaw County, where a four-engine plant produces about 3,200 kW of power each hour by converting landfill gas into electricity. Horton points out that that's enough to meet the energy needs of 2,500 homes, and it's an alternative to burning coal and consuming fossil fuels.
Waste Management has 13 landfills in Michigan, eight of which are using gas in an energy-related way. At about half of those, pipelines carry the gas to some kind of industrial facility, such as an automotive plant, to meet that company's thermal needs. One landfill in Ottawa County has a pipeline that runs six miles to Zeeland Farm Services, which uses the gas by-product in its soybean processing operations to make biodiesel.

In 2006, landfill gas energy projects in theUS prevented the release of more than 20 mm tons of carbon equivalent, according to the EPA. Experts claim that has the same environmental impact as eliminating the emissions of 14 mm cars, planting 20 mm acres of forest, or preventing the use of more than 169 mm barrels of oil.
The Whitefeather Landfill in Bay County's Pinconning Township hasn't gotten into the business of harnessing landfill gas yet, but its operator, Republic Services, claims it has hopes for the future. Landfill officials currently are focusing on controlling gas odours by collecting the gas and burning it onsite, said Brian Ezyk, area engineer for Republic.

Two other Republic landfills in Michigan are recycling landfill gas for electricity in Montrose and New Boston. The hope is to add Pinconning to the list, Ezyk said, but there are no concrete plans in the works just yet.
"There's not enough landfill gas being produced that would make it economically efficient," he explained, pointing out the high costs of constructing an electrical generating plant and the power lines to connect it to the Consumers Energy power grid. "Hopefully, someday, it will be economically viable to construct a power plant, but I don't know if it will happen or not," he said, though he says he can't deny the environmental benefits.
"It's true recycling: You're taking waste and converting it into electricity."

Horton said Waste Management got in the business of harnessing landfill gas nearly 20 years ago and now uses that gas to provide energy to 1 mm homes nationwide. He said the company's goal is to double that by 2020.
"It's a big part of what we do, and it's a big part of what we want to do more of in the future," Horton said.
Waste Management has 104 landfills nationwide that produce commercial quantities of gas, about 76 of which are parlaying that asset into electricity. Another 23 capture gas and send it into a direct pipeline to heat homes or to be used by businesses. As the value of renewable energy rises, and more incentives are provided, Horton said, landfills where harnessing gas might not be commercially viable now could be the hub of such activity in the future.

Consumers Energy, which is planning to double the amount of renewable energy it generates from 5 % to 10 % by 2015, currently generates renewable energy from multiple sources, including landfill gas from the People's Landfill in Saginaw County.
Detroit-based DTE also has vowed to invest millions of dollars in renewable energy in the coming years. Company officials said earlier this year that only 1 % of DTE's power currently comes from renewable sources, mostly biomass energy from landfill gas.