The Toronto Zoo, the largest zoo in Canada and third-largest in the world, put out a request for proposals yesterday to build a large anaerobic digestion facility that will convert manure from elephants, giraffes and hundreds of other animals under its care into biogas. The plan is to burn the biogas to generate electricity — up to 5 megawatts — and use the waste heat from both the digester and the generation plant to heat zoo exhibits (offsetting more than $1 million of natural gas used by the zoo). This is just the latest biogas project to emerge in Toronto, which also plans to take methane from a large landfill, a major wastewater treatment plant, and two organic waste processing facilities to generate electricity, or alternatively, to fuel city transportation fleets. In all, biogas projects recently approved by the Ontario Power Authority under the province’s feed-in-tariff program, as well as projects in the pipeline, total well over 100 megawatts.
The Toronto Zoo, I should point out, isn’t just taking care of its own business. Only 2 per cent of its waste — a combo of animal manure, beddings and organic waste from on-site restaurants — will feed the digester. The rest will be a combination of organic waste from commercial and retail establishments in the surrounding community. Read the full story in the Toronto Star.