The Environmental Commissioner of Ontario has published her Annual Energy Conservation Progress Report, entitled Every Drop Counts (the “Report”). The Report focuses on the nexus between water and energy and finding ways to reduce municipal consumption of both in Ontario. The Report focuses on some creative solutions for reducing greenhouse gas (GHG) emissions and energy and water consumption at the municipal level.
One solution proposed in the Report (and one that generated particular media interest) is to make use of the latent energy source provided by sewage. Municipal water and wastewater systems account for an average 38 per cent of a municipality’s energy consumption and 32 per cent of its reported GHG emissions. These are by far the largest shares of overall municipal energy consumption and GHG emissions, respectively.
Human waste contains energy that can be captured, by way of anaerobic digestion, as biogas. This energy could be used to power and heat treatment facilities, as fuel for municipal vehicles (such as buses), or diverted to a natural gas facility.
Currently, few wastewater plants use this kind of technology, though several are considering implementing it. The Report argues that it is time for municipalities to upgrade water and wastewater infrastructure to achieve the efficiencies for water and energy consumption created by this and other forms of technology.
The Report also suggests encouraging greater water conservation through municipal asset management planning, measures designed to encourage better consumer conservation practices, and water reuse practices, among other suggestions.