The scoop on how Waterloo's 'poop power' system will work
Waterloo, Ont.'s new dog poop power pilot project has been the talk of the country this week, with its promise of unleashing pet waste as a renewable energy resource.
Dubbed "poop power" by Mayor Dave Jaworsky, the pilot project starts with three pet waste containers placed in three Waterloo parks, including Bechtel Park, which has a leash-free dog zone. The project ends with biogas produced at the Bio-EN Power plant in Elmira.
CBC Kitchener-Waterloo spoke with Bill Higgins, director of business development at Sutera, a subsidiary of Canadian construction contractor Melloul Blamey. Sutera makes the containers that will store the pet waste. They're now working out the logistics for how the pet waste gets from parks to power plant.
So I put my doggie bag in the bin, then what happens?
Higgins: The Sutera pet waste container is a large concrete well, or vault if you will, that goes down about 6 feet underground. And it holds approximately three-quarters of a cubic yard, or 143 gallons of dog waste.
The reason we put it underground is so it stays cool. It's not out in the hot sun, where it is getting heated up and generating odours and attracting flies and maggots.
So by having such a large quantity, the park system or municipality, condominium board – whoever happens to own one – doesn't have to have it emptied every day, or every other day because of the unpleasant odours that come from dog feces.
How long before you need to empty it?
Higgins: Based on what the folks in Waterloo have told me, the one that's going into Bechtel dog park will probably be emptied once a week because of volume. The other two parks we don't know because we don't have any data as to how fast they'll fill up.
The product has been designed around emptying only when it's full – not when it smells. And that's the important thing, that's the important difference between this container and something that would be available above ground.
Who will pick it up?
Higgins: We have a company right now, contracted to do the pilot project. They have a vacuum truck and they will come in and vacuum the contents of the well out and take that to the bio-digester in Elmira.
How does this become energy?
Higgins: Dog waste contains methane, just like every other waste. So they have a very sophisticated bio-digester in Elmira and so far, its the first one we've found that will actually take dog waste.
Dog waste is extremely toxic. There are many pathogens in it, many more than in human waste or in livestock waste. And it needs to be treated differently. So you can't just compost it or send to just any bio-digester.
These folks in Elmira, have agreed to take the dog waste and they have a process where the dog bags are separated and taken out and then it's mixed in with other waste: some of it's livestock, some of it's organic waste that they buy, and it goes into a very sophisticated bio-digester.
For the next 30 to 90 days, the contents are processed by heat and stirred in an oxygen-free environment. The bacteria from the dog waste begins to digest the material and it releases bio-gases. The gases are collected, cooled and cleaned and they're used to run a generator -- two of them, actually.
What's left over is used to create fertilizer.
We don't have the exact statistics yet, but we think one of our containers will produce enough electricity to power 26 homes for a year.
The numbers we used: we assumed the container would be emptied every other week and, based on the weight of the dog waste that is in those containers, and the energy that's produced from that, we think we're going to get 26 homes powered per year out of each container.
Why is dog feces a problem for municipalities?
Higgins: Dog poop is one of the most challenging issues every park system and municipality faces. Frankly, dog poop is toxic. It has parasites, bacteria and viruses in it; pathogens that can live up to four years after that pile of dog waste has been washed away from the rain.
Those pathogens cause serious disease. Those pathogens can wash into our urban water systems. Studies show that between 20 to 30 per cent of all bacteria in urban watersheds is created by dog feces.