After Gutenberg

Writing for USA Today, Wendy Koch gives us a LMOP update. After Gutenberg readers may recall that LMOP stands for the federal Landfill Methane Outreach Program. So, this is a story about biogas (garbage to methane) and not about pyrolysis (trash to power).

Image credit: Environment Ministry Of Canada, Quebec

In June 2008 Waste Management, Inc. operated 281 landfills in North America; 100 already had some form of methane-to-energy capabilities; and, Waste Management announced plans for landfill gas-to-energy facilities at 60 more sites. Wes Muir noted a rise in the use of landfill gas; he attributed the rise to a variety of factors. “Higher energy prices make landfill gas cost-competitive, especially compared to other sources of renewable energy. Second, utilities are looking for new sources of renewable energy to meet renewable portfolio standards, and landfill gas is especially valuable to them because it provides base load power. There’s also a real demand from consumers for greener energy and many of them are taking part in voluntary programs and are willing to pay more for power derived from renewable sources.”

Nationwide, the number of landfill gas projects, which convert methane gas emitted from decomposing garbage into power, jumped from 399 in 2005 to 519 last year, according to the Environmental Protection Agency.

“There’s certainly an increasing interest in doing these projects,” says Rachel Goldstein, leader of EPA’s Landfill Methane Outreach Program, which provides technical help to develop them. She says they are popular because they control energy costs and reduce greenhouse gas emissions.

“As garbage decomposes, it creates gas that is half methane, which has 20 times the global warming potential of carbon dioxide, according to the EPA. Instead of letting the gas escape into the air, these projects collect the gas and treat it so it can be used for electricity or upgraded to pipeline-grade gas. The projects power homes, buildings and vehicles.”

According to the World Meteorological Association Atmospheric methane was about 700ppb before the industrial era. Since 1750 it has increased 157% and anthropogenic sources are largely responsible for the increase. Anthropogenic sources account for 60% of the total concentration of methane now in the atmosphere.

The globally averaged mixing ratio of methane (CH4) in 2008 was 1,797 ppb, an increase of 7ppb from the previous year. While CH4 level was stable for seven years (from 1999 to 2006), both 2007 and 2008 show a significant increase. Methane contributes 18.2% to the increase in overall global radiative forcing since 1750.

Anthropogenic sources of CH4 emissions include ruminants, rice agriculture, fossil fuel exploitation, landfills and biomass burning. Harvesting methane from decomposing manure from factory farms and decomposing garbage in landfills is an important way that we can mitigate this potent green house gas.