Tons of trash accumulates daily at the 800-acre Bannock County
Landfill producing gases that pollute the air. But Bannock County Commissioners are completing an impressive project that will convert the gases from the county’s trash to energy, satisfy the Environmental Protection Agency (EPA) mandates, and even generate revenue for the county.
Bannock County’s Landfill project will be one of three gas-to-energy facilities in Idaho – although more are being discussed. As of June 2012, there were 594 operational landfill gas-to-energy projects in the United States.
As garbage decomposes, it creates methane, which has 20 times the
global warming potential of carbon dioxide according to the Environmental
Protection Agency (EPA). And for that reason the EPA is requiring a reduction in greenhouse gases released from landfills. So instead of letting the gas escape into the air, gas-to-energy projects collect landfill gases and generate energy creating a beneficial use from a detrimental gas.
When the Bannock County Landfill reaches 50 metric tons of Non Methane Organic Compound (NMOC) emissions, EPA rules will require it to reduce landfill gas emissions escaping into the air. According to Project Engineer, Stephen Freiburger, the Bannock County Landfill is expected to reach that threshold by 2024.
For several years Bannock County Commissioners have been actively seeking an opportunity to manage landfill gases and generate county revenue. Recently, commissioners decided the gas-to-energy project looked promising so they allocated $4.0 million from landfill user fees and moved ahead with project engineering and construction.
Today Phase 1 (collection system and flare) of the project is nearing completion. Thirty-two gas wells ranging from 30 to 102 feet in-depth
and over 17,000 feet of collection piping are installed. By late 2012 an open
gas flare will be installed at the landfill and tested for 3-6 months to
analyze gas flow rates and quality.
In 2013, Phase 2 (generation system) will be underway. The electrical generation system will be installed and online for power production in 2014.
When the system is fully installed the landfill is expected to produce 1.0 to 3.2 megawatts of electricity. The wattage is produced from burning a mixture of 45-55% methane, carbon dioxide, and other gases.
By 2014 the landfill will generate clean power for up to 3,000 homes. Once the system is paid for in 6-10 years, annual gas-to-energy project revenue could exceed $0.5 million per year.
Idaho Power will buy the generated electricity. Unlike other energy sources, landfill gas provides constant power, making it more desirable than other renewable energy sources.