In “Fact #951” of its ongoing series on matters related to renewable energy, electric vehicles, emissions, and energy efficiency, the US Office of Energy Efficiency and Renewable Energy has highlighted the fact that a disproportionate portion of carbon dioxide emissions and fuel use are the result of medium and heavy truck use.
To explain that, while only around 4% of the total vehicle “population” is a medium or heavy truck, such vehicles are responsible for around 30% of total on-road carbon dioxide emissions and more than 25% of fuel use — mostly owing to the larger sizes and weights of the trucks themselves, the heavier payloads being transported, and the greater distances (at higher speeds) traveled.
Travel at high speeds, especially for vehicles with drag coefficients as low as medium and heavy trucks, is particularly fuel inefficient — travel at lower speeds is, as a result, less impactful with regard to fuel use and carbon dioxide emissions.
To provide figures that are more specific, with an estimated vehicle total of 240 million for cars and light trucks (96% of total), and an estimated vehicle total of 11 million for medium and heavy trucks (4% of total), cars and light trucks accounted for 127 billion gallons of fuel use in 2014 as compared to 44 billion gallons of fuel use that year by medium and heavy trucks.
These figures relate to 1,051 million metric tons of carbon dioxide emissions in 2014 by cars and light trucks (71% of total emissions that year) and 421 million metric tons of carbon dioxide emissions in 2014 by medium and heavy trucks (29% of total emissions that year).
These figures are only for the US, it should be remembered — the situation elsewhere will likely be somewhat different but follow the same general point.
Notably, these comparisons don’t take into account buses, motorcycles, or scooters.
Tip of the hat to Bob Wallace for this story.