Waste emissions increased by 2% to 1.8 MtCO2eq in 2022 and account for 3% of the GTHA’s total emissions. The 2022 waste emissions are estimated based on population growth, assuming per capita emissions remained the same as in 2021.
The predominant component of waste emissions is methane, released as organic waste is broken down by bacteria in landfills.
As a greenhouse gas, methane is significantly more potent than carbon dioxide, particularly within its first 20 years in the atmosphere. While this inventory uses the conventional 100-year carbon equivalency for methane, a 20-year carbon timeframe would roughly show triple the emissions, better representing the actual amount of greenhouse gasses released in the short term.
Starting in 2021, the landfill methane recovery rate and waste compositions were updated for each region to better represent their specific waste characteristics. The City of Toronto and Peel Region report a higher methane capture rate of 82% and 85%, respectively; Halton and York Region report a recovery rate is 75%; and the City of Hamilton reports a capture rate of 51%.
Landfill gas management systems are an important tool for reducing waste emissions as they allow methane to be captured and subsequently flared or used to create low-carbon energy. However, the most effective way to reduce waste emissions is to prevent waste from entering landfills altogether.
To achieve this, we will need to transition away from single-use products and strive to develop a robust circular economy that prioritizes the reuse of resources. Many municipalities have taken steps in this area, prioritizing it in their long-term waste management plans. TAF will monitor the impacts of such initiatives in the coming years.