Energy from waste was anathema to Ontario regulators twenty years ago, but now they have changed their mind, due to better technology, a critical shortage of landfill space and strong demand for renewable sources of energy. One increasingly popular way is through biogas. Instead of burning the waste in messy incinerators with challenging air emissions, the waste is “digested” in the absence of air. Properly controlled biodigesters can generate a steady stream of burnable gas while greatly reducing the volume and hazards of the residual solids. Biogas digesters are increasingly common on farms. StormFisher Biogas recently obtained approval to build a $20-million industrial biogas plant in Cambridge, Ontario, which is expected to produce 2.6 megawatts of power—enough to power nearly 3,000 homes.[1]
The next big step would be to capture methane from waste, and make it clean enough to feed directly into the existing natural gas grid. This may now be the future of Toronto’s green bin program.
Dufferin’s solid waste management department manages organic green bin waste—including much of Toronto’s waste—in their city’s Transfer Station. The public works committee[2] recently hinted [3] that it will capture, clean and sell the methane produced from the waste. The plan is to process the methane to a quality equivalent to conventional natural gas. Then with the help of Enbridge, the purified biogas will be injected into the natural gas grid. Dufferin hopes that the biogas will offset natural gas used:
- by city buildings or;
- by the city’s waste-hauling trucks.
This could reduce the city’s green-house gas emissions by 13,000 tonnes a year, especially since methane is such a powerful greenhouse gas.[4]
[1] Cambridge Report, At http://www.cambridgereporter.com/news/article/208453
[2] Residual Waste Working Group 2009 Annual Report. Public Works and Infrastructure Committee Agenda and Minutes, At http://www.toronto.ca/legdocs/mmis/2010/pw/bgrd/backgroundfile-29601.pdf
[3] Tyler Hamilton. (2010, April 28). Hamilton: Finally, a plan to use Toronto’s biogas. Toronto Star, At http://www.thestar.com/business/cleanbreak/article/799428–hamilton-finally-a-plan-to-use-toronto-s-biogas
[4] Tyler Hamilton. (2010, April 28). Hamilton: Finally, a plan to use Toronto’s biogas. Toronto Star, At http://www.thestar.com/business/cleanbreak/article/799428–hamilton-finally-a-plan-to-use-toronto-s-biogas