Timeline: 2018 onwards
The City of London’s Wastewater Treatment Operations Division incinerates the dewatered waste solids at Greenway. A by-product of the incineration process was the heat which was lost through the facility’s exhaust stack. Some of this heat had been captured and used to heat areas of the plant, but the remaining waste heat energy represented an opportunity for the City.
The earliest investigations into utilizing waste heat for power generation were undertaken in 2012, but the design and procurement of an ORC power generation system for Greenway began in earnest in 2018. Commissioning was completed in October 2021.
It is expected that the power generated by the ORC system will be capable of offsetting a quarter of the power consumption at Greenway, the City’s largest wastewater treatment plant, saving a projected $600,000 per year in electricity costs. The energy consumption reduction achieved through this project alone is expected to total 3,600 MWh per year and accounts for over 40% of the City’s 2019-2023 Corporate Energy Conservation and Demand Management Plan’s overall target.
In terms of greenhouse gas emissions, the reduced energy will cut the City’s greenhouse gas emissions by an estimated 800 tonnes of CO2 per year – the equivalent of taking 200 cars off the road. In addition, Operations staff are working to optimize the operation of the incinerator to both increase power production capability while also targeting a reduction of greenhouse gas emissions in the incinerator flue gas discharge. The results of these efforts will become clear in the coming months and years.
Action: Energy Generation from Waste