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Powered by recycling. Literally!

We’ve figured out how to turn trash into treasure. Not the wooden chest of gold coins-type treasure, but treasure for our modern world: clean energy. The evidence: my city, the city of Toronto, has a new garbage truck with an engine (a Cummins Westport ISL G) that’s capable of running on compressed natural gas, including biogas. And where are they planning to get that source of biogas? From composting operations that handle the green bin waste (kitchen waste) removed from Toronto curbsides by… Toronto garbage trucks.

“Our two green bin processing facilities have the potential to produce enough natural gas to take our entire fleet of 300 waste trucks off diesel,” says Geoff Rathbone, the City of Toronto’s General Manager of Solid Waste Management Services. “Creating natural gas from kitchen waste will be the first operation of its kind in North America.”

Replacing diesel trucks with lower-emission biogas trucks is all a pilot project at this point, but the city is motivated: its Green Fleet Plan calls for new medium and heavy-duty trucks in order to reduce fuel consumption, fuel costs, smog and greenhouse-gas pollutants. For more information on the plan, click here.

Next, let’s hope that Toronto and other municipalities tackle incineration to deal with all that garbage waste that cannot be composted or recycled. Burning this material generates energy as well, and the processes can be controlled in a way that doesn’t contaminate the environment (read about it here). That would save us a heck of a lot of money (and, of course, climate-impacting CO2) compared to trucking garbage to landfills. C’mon Canada, Japan is doing it, Denmark is doing it… we can do it!

What resource is endless? Well, none. But as long as we’re around, and the animals we like to eat are around, there will be endless, er, waste product. Number one and two. You get the idea.

Using tail-end waste is, of course, popular for fertilizing crops, and some have used it as a fuel source in the past. But cropping up across Canada are small-scale energy installations that harvest methane from animal waste and make it available as a potent energy source, reducing farmers’ energy costs and capable of supplying the local energy grid with electricity. Biodigesters can convert huge quantities of waste (including manure, but also restaurant and food processing waste) into biogas and liquid fertilizer.

Using biodigesters conserves grid energy, reduces odours and insect pests and reduces pressure on the environment (primarily through reducing methane emissions, one of the most harmful greenhouse gasses in terms of climate change). They also help protect water sources because pathogens have been largely digested, although depending on how the resulting manure is handled, agricultural runoff, with its excess nutrient, can still be an issue.

So how much power can a biogas plant generate? Some larger installations offer enough to power and heat the farm, then sell enough power into the grid to provide for over a hundred homes. According to this fact sheet, a small-scale (100 head) cattle farm could produce 1,227 kWh of electricity and 5.5 GJ of heating power per year and save the farmer over $10,000 per year.

A daydream of mine: I would love to see highway rest stops powered by on-site biodigesters. Think of it: all thousands of people a day are stopping for a bathroom break, and a cup of coffee and a muffin (preparing for the next bathroom break)!

For a rare opportunity to get a tour of how a biodigester works, check out Canada’s Outdoor Farm Show in Woodstock, Ontario. Tours are on now through September 16.

What do you think, can we accept being powered by what we prefer to leave behind?