Landfill Gas - Creating Energy & Reducing Emissions
Landfill gas is an increasingly important energy source in the Alameda’s renewable power portfolio. Over the last few years we have made a concerted effort to increase the percentage of our power supply that comes from this dually beneficial energy source.
The most remarkable aspect of landfill gas is the fact that while landfill gas is providing energy for the power grid, it is also preventing the emission of naturally occurring methane gas into the atmosphere. No other energy source results in such a win-win situation. In addition, solid waste is a plentiful resource, and will always be generated.
Energy from an Unlimited Supply of Waste
Landfill gas is created as organic solid waste decomposes in a landfill. Landfill gas consists primarily of two gases -- methane (the primary component of natural gas) and carbon dioxide (CO2). Methane and CO2 are two of the three main greenhouse gases (GHGs), with methane being the more potent contributor to global warming.
As methane escapes from the landfill, it can be captured, converted, and used as an energy source. Landfill gas is the only renewable energy source that when used, directly reduces air pollution, by reducing the emission of greenhouse gases.
According to the EPA, landfills are the largest human-related sources of methane in the country. The amount of methane produced depends on the rate of decomposition, the quantity and moisture content of the waste, as well as the waste management practices at the landfill. If these gases are not captured, they are emitted into the atmosphere where they contribute to the rising concentration of greenhouse gases.
How Landfill Gas Creates Electricity
Landfill gas is extracted by drilling wells into landfills and collecting the gas through pipes placed inside them. Once the gas reaches a central collection point it is processed and combusted in a gas-fired engine to produce electricity.
Because methane sourced from landfills is produced naturally throughout the day, landfill gas projects typically operate as base load power plants and achieve capacity factors over 90%. This high capacity factor and competitive fuel price relative to natural gas, landfill gas projects have the double benefit of being economical and effective in reducing greenhouse gases.
Landfill Gas - Facts and Figures
- Qualifies as a CEC eligible resource under California’s Renewable Portfolio Standard
- Reduces greenhouse gases by re-purposing the emissions of naturally occurring methane gas that would otherwise be emitted into the atmosphere.
- Offsets the use of electricity from non-renewable sources, such as coal, natural gas, and oil, reducing the resulting air pollution
- Satisfies CAISO criteria for meeting local area capacity requirements