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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?

Landfills are a thing of the past. Trouble is, they’re a thing of the present too. And future, whether we like it or not.

One of the seminars I attended at Saturday’s Toronto Stewardship Forum was about the new book HTO (Coach House Books, 2008, $24.95), a history of Toronto’s relationship with water. One of the book’s editors, Wayne Reeves, talked about how Toronto has used its waterways over the years, explaining that, today, the city is trying to resuscitate and reintegrate ecological features around waterways to better deal with rain water (and, of course, to create a healthier city).  But a key challenge for the city is its historical landfills.

Just like the landfills we’re creating today, dump sites of 50 and 100 years ago are in areas we consider acceptable (OK, maybe  tolerable is a better word) for that sort of use. It turns out that, even up to the 1950s, Toronto’s ravines were used for dumping garbage. And guess what? It’s still there, taking up space, interrupting local ecology, and it’s today’s problem and the city tries to mitigate chemical runoff from whatever people here threw out all those years ago.

So where should we dump our garbage? I’d say nowhere. I think, like Japan and many other places, we should see our garbage as fuel. Everything that’s left after recycling and claiming materials should be used to power modern, non-polluting incineration plants (even gasification), or processed in biodigesters, set up for small populations. That way we’ll reclaim power for use locally.

What do you think, can we eliminate garbage?