Cars are the largest source of transportation emissionsRoad vehicles are the primary source of transportation-related greenhouse gases, with passenger cars accounting for more than 50 percent of the sector’s total emissions. UK passenger cars emissions totaled 57 MtCO₂e in 2021 – an increase of roughly 10 percent from the previous year. Road freight vehicles were the second-largest source of transportation emissions that year, with heavy goods vehicles (HGVs) and light-duty vehicles (LDVs) emitting a combined 40 MtCO₂e.
Road transportation is not only a major source of greenhouse gases but also a significant emitter of air pollutants such as PM2.5 and nitrogen dioxide. These pollutants are harmful to humans and have caused numerous health issues for people living in congested areas such as London. This has led to more than 15 low emissions zones (LEZs) being introduced in urban areas across the country in a bid to improve air quality.