Harnessing the Power of Landfill Gas

Landfill sites generate over a quarter of the methane emissions caused by human activity in Canada, sending 1.2 million tonnes of this potent greenhouse gas into the atmosphere each year. Because the global warming effect of methane is 21 times greater than that of carbon dioxide, this is the equivalent of greenhouse gas emissions from more than six million cars—or 40 per cent of all the passenger vehicles in the country.

Methane is one of the main components of landfill gas—an odourless, colourless gas generated by the anaerobic decomposition of degradable organic waste. Although its composition can vary, landfill gas is typically half methane and half carbon dioxide, with trace levels of sulphur compounds and volatile organic compounds. Landfill sites begin producing landfill gas in their first year, and can continue producing for up to half a century.

Over the past decade, innovative technologies have been developed to capture this gas by drilling deep into landfill sites and pumping it out through a network of pipes. The captured gas is either flared off or piped to nearby facilities for use as fuel in heating buildings or generating electricity. Burning landfill gas not only converts methane to carbon dioxide, but also destroys most of its harmful components—which can cause nuisance odours, stress on vegetation, smog, and a risk of fire, explosion and asphyxiation. The methane produced by Canadian landfill sites contains enough energy to heat more than 600 000 homes a year.

Environment Canada has been working with Natural Resources Canada, provincial departments and the private sector to raise awareness of the energy potential of landfill gas by holding workshops and publishing guidebooks on the subject, as well as supporting research into new and innovative technologies. These include a new cryogenic purification process that can separate landfill gas into liquified natural gas and high-purity carbon dioxide, and the use of automobile engines to generate electricity on small landfill sites.

The increased availability of cost-effective and efficient technologies has resulted in a 40-per-cent increase in landfill gas capture in Canada since 1990. Today, nearly 300 000 tonnes of methane are recovered at 33 sites across the country annually, reducing greenhouse gas emissions equivalent to six megatonnes of carbon dioxide. However, this still represents just a quarter of the total landfill methane produced in Canada each year.

Bars represent total landfill gas generated from all landfill sites in Canada, with portion captured indicated in green.

About 70 per cent of the recovered gas is used as energy, most of it at large-volume landfills located near major urban centres. However, the potential also exists for many medium and small sites to generate revenue from landfill gas recovery projects. This spring, a report will be released exploring ways to make landfill gas a more viable and attractive source of energy, and identifying 40-50 sites in Canada that have the greatest potential for the expansion or installation of recovery systems.

Experts estimate that the volume of landfill methane captured in Canada could be doubled within the next five years--significantly decreasing Canada's greenhouse gas emissions, and reducing the impact of human activity on global climate change. For more information on landfill gas, visit the National Office of Pollution Prevention web site at www.ec.gc.ca/nopp/lfg/bulletin/indexe.htm.

Landfill Gas in Action

Jackman Landfill Site—Aldergrove, British Columbia

• since 1995, LFG used to heat commercial greenhouses and provide CO₂ to plants.
• GHG reduction equivalent to 18 000 tonnes of CO₂.
• closed site, 0.5 million tonnes of waste.

Port Mann Landfill Site—Surrey, British Columbia

• since 1993, LFG used to fuel dryers in wallboard manufacturing plant.
• GHG reduction equivalent to 40 000 tonnes of CO₂.
• closed site, 4 million tonnes of waste.

Clover Bar Landfill Site—Edmonton, Alberta

• since 1992, LFG piped to generating station, where it produces enough power annually for 4200 homes.
• GHG reduction equivalent to 182 000 tonnes of CO₂.
• active site, 12 million tonnes of waste.

Keele Valley Landfill Site—Vaughan, Ontario

• since 1995, LFG has operated turbines at electrical generating station; produces enough power for 22 000 households annually.
• power sale nets annual royalties of over $1.5 million for cities.
• active site, 21.5 million tonnes of waste.

Complexe environnemental de Saint-Michel—Montréal,Quebec

• since 1996, LFG has operated boilers and steam turbine at electrical generating station; produces enough power for 16 800 homes annually.
• GHG reduction equivalent to 1.1 million tonnes of CO₂.
• gas sale provides Montréal with royalties of over $1 million per year.
• active site, 33 million tonnes of waste.

Lachenaie Landfill Site—Lachenaie, Quebec

• since 1996, LFG used to fuel reciprocating engines at on-site electrical generating plant; produces enough electricity for 2450 homes annually.
• GHG reduction equivalent to 250 000 tonnes of CO₂.
• active site, 7 million tonnes of waste.

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