By James Noble
December 12, 2013
The nation’s largest facility for turning manure and food processing waste into electricity just went online in Lethbridge, AB. The project is a unique partnership between private, provincial and municipal stakeholders and took more than 10 years to get the $30 million project from concept to completion.
The state-of-the-art biogas facility has the capacity to process more than 100,000 tonnes of farm waste per year and is capable of producing 2.8 MW of electrical power today, and up to 4.2 MW with additional generating units in the future.
The anaerobic digestion process takes roughly 21 days, during which organic waste breaks down into compost and methane gas. The gas can be converted into electricity, which can then be delivered to Alberta's energy grid. The technology uses bacteria to break down organic matter in an oxygen-free environment without using large quantities of water.
Generating electrical and thermal energy through anaerobic digestion of organic materials reduces greenhouse gas emissions significantly, as manure is typically stored in open manure lagoons, which allow methane to freely escape into the atmosphere. The Lethbridge manure-to-electricity facility is expected to reduce the equivalent of 224,000 tonnes of carbon dioxide by 2020.
In addition to delivering renewable energy, anaerobic digestion technology offers a number of other significantenvironmental and economic benefits. Odours are reduced by up to 75 per cent and pathogens such as E. Coli and Salmonella are destroyed in the anaerobic digestion process, thereby protecting human and animal health from water or food contamination. Further, the process can benefit local farming operations, as the liquid byproduct is rich in nitrogen and can be used as fertilizer while the solid sterile byproduct can be used as bedding for farm animals.
Other large- and small-scale biogas projects are already operating in Canada. The Bakerview EcoDairy in Abbottsford, BC operates a biogas generator that produces enough power for the dairy's electrical systems with surplus power feeding into BC Hydro's power grid.
