Despite the significant progress made over the past 20 years in reducing particulate matter, nitrogen oxides (Nox), and greenhouse gas (GHG) emissions, the trucking sector continues to be criticized as a major polluter.
However, a recent report from the Observatoire sur le transport routier des marchandises (OTRM) at Université Laval, in partnership with the Fondation pour la formation en transport routier, highlights data showing the industry has already made notable gains in energy efficiency.
Heavy-duty trucks account for 5.2% of GHG emissions
According to the report, based on the most recent data from Environment and Climate Change Canada in March 2025, the transportation sector — which includes air, road, rail, marine, and other modes — accounts for 28% of Canada’s total GHG emissions. That’s 196 megatonnes of CO₂ equivalent (Mt CO₂e) out of a national total of 708 Mt.
Road transportation alone is responsible for 61% of the transportation sector’s emissions, or 120 Mt CO₂e. Of that, diesel-powered heavy-duty vehicles account for 37 Mt –equivalent to 5.2% of Canada’s total GHG emissions. For comparison, gasoline-powered light-duty trucks emit 53 Mt, though those emissions are spread across a much larger fleet operating over shorter distances.
In Quebec, the situation shows some unique characteristics. The État de l’énergie au Québec 2025 report, produced by the Energy Sector Management Chair at HEC Montreal, reveals notable trends in the evolution of the freight transportation fleet between 1990 and 2022. Over this 32-year span:
- The number of light-duty trucks increased by 346%
- The number of medium-duty trucks rose by 148%
- Heavy-duty trucks experienced a more moderate increase of 41%
However, the standout figure is this: today, heavy-duty trucks in Quebec travel an average of 94,000 km per year — an increase of 77% since 1990. Despite this, they accounted for only 8.5% of Quebec’s GHG emissions in 2022 — a higher proportion than the national average, but also a sign of some control over their environmental impact.
Real gains in efficiency
The numbers also show that the industry’s efforts to reduce fuel consumption are paying off.
In 2022:
- Medium-duty trucks averaged 18.8 L/100 km, an improvement of 32% since 1990
- Heavy-duty trucks averaged 27.1 L/100 km, a 36% reduction over the same period
National data reflects this trend as well. According to Natural Resources Canada, between 2000 and 2021:
- The energy intensity of heavy-duty trucks (measured in megajoules per tonne-kilometre) fell by 16.2%, from 2.02 MJ/tkm to 1.69 MJ/tkm
- During the same period, GHG emissions per tonne-kilometre dropped by 16%
These figures mean that each tonne of freight transported today requires less energy and emits fewer greenhouse gases than it did two decades ago.
The report concludes: “These results confirm the success of the industry’s ongoing efforts to improve energy efficiency.”
