If nothing is done, trucks used to ship goods by road will produce as much pollution as coal used in the power and industrial sectors combined, a report found.
A report published Monday by the International Energy Agency found that if no improvements are made to the global fleet of heavy trucks, oil demand from the sector will account for about 40 percent of the projected 2050 total demand growth.
The sector already accounts for about 30 percent of total transport-related carbon emissions and about 20 percent of total emissions of nitrogen oxides, the primary components of air pollution. Demand growth means that road freight will by 2050 produce the equivalent emissions of carbon dioxide as is expected for coal use in the power and industrial sectors combined.
"For far too long there has been a lack of policy focus on truck fuel efficiency," IEA Executive Director Fatih Birol said in a statement. "Given they are now the dominant driver of global oil demand, the issue can no longer be ignored if we are to meet our energy and environmental objectives."
By improving freight logistics, aerodynamics and finding alternative fuels, the IEA said energy use from road freight could decline by 50 percent and emissions could move lower by 75 percent by 2050.
Including passenger vehicles, the entire transportation sector accounts for the bulk of total energy used. Only four countries have energy-efficiency standards for heavy trucks, compared with 40 countries with standards for passenger vehicles.