Biogas is produced from the biological breakdown of organic matter in the absence of oxygen and is produced by a process called anaerobic digestion. The biogas is obtained from plant, animal and human waste, crop residue, waste paper, and municipal solid waste. Methane gas that is contained in the biogas can be separated, purified, and used to run reciprocating engines or gas turbines to generate electricity.
Burning the methane in biogas also emits a large amount of heat. This can be used to heat surrounding buildings and help preheat the digesters, since biogas production increases with higher temperatures. Utilizing the waste heat in addition to generating electricity called cogeneration.
Benefits for participants include heat and electricity savings and the prospect of revenues from energy production. Biogas operations could potentially serve as training facilities for biogas technicians through partnerships with local colleges and universities. Other benefits include the reduction of shipping costs of sending raw manure off-farm because of regulations regarding the ratio of manure to field coverage in the Nutrient Management Act from OMAFRA.
Even though biogas utilization involves the burning of methane, the carbon dioxide released is not new to the atmosphere. The plants and animal waste that was used to create the biogas absorbs the carbon dioxide from the atmosphere; therefore, burning the methane from the biogas is only reintroducing the carbon dioxide back into the atmosphere, not increasing greenhouse gas emissions.
A number of biogas projects are in various stages of development throughout Midwestern Ontario. The success of these projects will depend on their ability to overcome the barriers and risks identified in the sector overview. Until then, slow growth is expected within the industry over the coming years.