Skyline Energy explains: What happens inside a digester?

Anaerobic digesters are the equipment used to create biogas. They hold and contain organic waste materials in an anaerobic (oxygen-free) environment to allow bacteria to decompose, or “digest,” the waste. This type of decomposition is a natural process that also occurs in climates like swamps and ponds.

Stages of digestion inside an anaerobic digester

1. The digester has an inflow of the organic waste material. The insider of the digester is surrounding by a heat element, while mixers work within the digester to further break down the waste.
2. The complex compounds in the waste (such as fibre and protein) are broken down by aerobic bacteria into smaller carbohydrates or peptides. They are then broken down further into organic acids.
3. Anaerobic bacteria use these acids for energy and produce biogas, which is a mixture of methane, carbon dioxide, and a small amount of other gases. Biogas can then be used as an energy source.

As biogas is produced inside the digester, so is digestate, a high-nutrient compound with a sludge-like consistency, which can be used as compost, fertilizer, soil amendments, or animal bedding.

Skyline Energy is a proud member of the Canadian Biogas Association. We believe that biogas can play a major role in accelerating Canada’s clean energy generation objectives, and we’re excited to see the biogas sector gaining momentum across the country.

¹ MW/DC: Megawatt of direct current energy; a unit measurement of the output of power.
² Expected Annual Generation is projected by an independent third-party and is calculated as an expectation of annual output based on analysis of a number of inputs, including historical production, system efficiency, and historical weather data.
³ MWh: A measurement of energy usage; the amount of energy one would use if keeping a 1,000 kilowatt machine running for an hour.
⁴ Estimated Gross Annual Revenue is calculated as: (size of system, measured as kilowatts) x (production factor of system, measured as kilowatt hours generated per kilowatt) x (tariff rate, measured as revenue per kilowatt hour generated)