Manure digesters that capture and burn methane for the production of electricity aren’t uncommon. They’re a great way to deal with the large volumes of animal waste that accumulates on farms, as we’ve seen. But why not a zoo, too? That’s the question they’re asking in Toronto, where an effort called ZooShare is under way to convert the poop to power.
Mind you, as it stands, the animal droppings from the Toronto Zoo are put to some good use. According to the Globe and Mail, where we first came across this story, 3,000 tons of the stuff every year goes into an open compost pit, partly to make fertilizer. That process, however, doesn’t address one of the biggest environmental problems posed by animal waste – the methane released into the atmosphere as it decomposes.
The goal with ZooShare, which has received funding from the Ontario Power Authority as well as the city of Toronto, is to build a biogas plant consisting of a primary digester, two storage tanks and a 500-kilowatt generator. The plant would receive all of the zoo’s manure, as well as 12,000 tons of local food waste, including fat, oil and grease.
Power produced at the plant would go to the grid, aided by Ontario‘s robust feed-in tariff program. In addition, liquid and solid digestate left behind by the anaerobic process, high in nitrates and phosphoates, would be sold as fertilizer, and heat from burning the methane would be used for both heating and hot water.
As a public-private co-op, ZooShare, with a $5.4 million budget, is looking for members and private investors, promising a seven percent annual return to participants’ retirement accounts. We aren’t endorsing that you should invest in, but it is an intriguing idea to say the least.