Biogas: Electric Power from Animal Waste

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biogas

Drive on a rural road in southern Ontario, and sooner or later you will come across a cattle farm. There’s a pretty good chance that you will smell it before you see it, the manure from hundreds of cows makes a striking odour.

Cows and cattle farms are not faring well in environmental literature these days. Cows themselves are potent generators of greenhouse gases, and they require feed that consumes land and resources that could be better spent on crops to feed people directly. They fare even less well from their neighbours, due largely to the smell.

However, on a few farms across Canada, farmers are working to change that impression. Rather than just leaving the manure to rot in the fields, they are collecting it in order to generate fuel. Which, incidentally, also controls the smell.

“The thought of all cattle farms being labelled factory farms disturbs me … we counter this myth by engaging in environmentally, and animal, friendly practices,” says Laurie Stanton, a third generation dairy farmer.

On the Stanton farm, all organic waste is collected up and fed into an Induced Blanket Reactor (IBR), also called a biodigester. The eight tanks hold about 117,000 litres of liquid waste, which is fermented to produce methane.

biodigester

The methane is then used to fuel generators that supply power to the farm, and eventually, the plan is to provide enough power for the nearby town of Ilderton, Ontario. Current power production is 300 kilowatts, but they expect to have production up to 1.3 megawatts by early this year. This methane would have otherwise been released into the environment, where it is a potent greenhouse gas.

In addition to providing enough power for the farm, and extra besides, the biodigester also creates a clear, odourless liquid that is an excellent fertilizer, along with a fibrous substance is used as bedding for the cattle. Both of these products help the farm reduce it’s environmental impact.

The Stanton farm is one of six large-scale cattle farms in Canada that generate power from their cow’s manure. In this, though, Canada lags behind many European countries. Germany, for example, has over 4000 biodigesters on farms, generating more than 1600 megawatts of power. That’s more power than would be generated by 3 typical nuclear power reactors.

There are regulatory barriers in Canada that act against biogas generation, including the demand by Hydro One in Ontario that producers, even small-scale producers, meet all the costs required to connect their power projects into the provincial grid. Some of the equipment can cost over $250,000. Add to that the low amounts Hydro One pays for small-scale power, the possibility of rezoning requirements, property tax increases, and the general difficulties in getting approval to connect to the grid, and the generation and sale of biogas power is problematic.

Biogas power production is green, is sustainable, and helps to reduce methane emissions from cattle farms. Canada needs to create a regulatory system that rewards and encourages this sort of small power generation. Small-scale, community-based power generation and environmental cleanup projects are a big piece of the puzzle on how to wean ourselves away from coal and oil to supply our power requirements, now and into the future.