Power from poop: Wastewater upgrades in Calgary to harness biogas

The City of Calgary says it's investing more than $1 billion to upgrade its largest water treatment plant to make the facility self-sufficient in terms of electricity.

The Bonnybrook Wastewater Treatment Plant is currently undergoing work to upgrade the facility to improve its capacity as well as installing a system that will help save on utility costs and greenhouse gas emissions.

The new system will add a 4.6-megawatt gas turbine and 0.6-megawatt steam turbine, both of which will use biogas, a byproduct of wastewater treatment, for power generation and heating.

The city says this upgrade will "substantially reduce the plant's utility costs" by cutting down on its reliance on external power sources.

Once installed, it's also possible the excess power produced at Bonnybrook could be diverted back into the grid.

Officials say the upgrades will also have a positive impact on the environment.

"The new system will reduce Bonnybrook's greenhouse gas emissions by about 17,500 tCO2e/year by reducing natural gas use and electricity import, minimizing biogas flaring, and improving plant energy efficiencies. This is roughly the equivalent of taking 5,600 cars off Calgary’s roads," said Orin MacIntyre, lead wastewater treatment engineer.

With this new system installed, the city says Bonnybrook is now also on the Alberta Electric System Operator website as one of 13 sites in Alberta that produce power from biomass.

More information on the Bonnybrook upgrade can be found online.