Air quality and health impacts of heavy-duty vehicles in G20 economies

On-road diesel vehicles are the leading contributor to air pollution and associated disease burdens. Besides the impact on air quality and public health, black carbon from diesel engine exhaust produces significant near-term climate warming. This study analyzes the health and climate impacts associated with projected diesel HDV exhaust emissions in G20 economies under four scenarios: currently adopted policies, expanded adoption of Euro VI-equivalent standards, potential next-generation emission standards, and accelerated fleet renewal programs.

Expanded implementation of world-class standards in G20 economies in the 2023–2025 timeframe would reduce NOx by 45%–85% over the next two decades. Likewise, in G20 countries that have adopted these standards, black carbon emissions are projected to fall by 85%–99% over the next two decades compared with 2020 levels.

Next-generation standards are also key to sustaining NOX emission reductions from HDVs. These standards could bring NOx levels down by 60%–95% from 2020 levels in 2040, compared with the 40%–80% projected under Euro VI-equivalent standards. Moreover, implementation of next-generation standards in G20 economies could avoid more than $5 trillion of health damages over the next three decades. These potential benefits are significant not only for countries that have already implemented current world-class standards but also for countries that are planning to implement Euro VI-equivalent standards within the next several years.

Next-generation standards coupled with accelerated fleet renewal policies would achieve the greatest benefits by a wide margin. Cumulative avoided premature deaths attributable to diesel HDV emissions in G20 economies from 2020 to 2050 would total 4 million under a next-generation with 16-year fleet renewal scenario. This is four times the number under the expanded world-class plus 16-year renewal scenario. In countries like Germany, France, Italy, and other EU nations, accelerated fleet renewal policies coupled with next-generation standards are expected to achieve at least twice the monetary health benefits as either world-class, Euro VI-equivalent with fleet renewal or next-generation alone. Next-generation policies combined with accelerated fleet renewal policies are expected to yield $6.8 trillion of cumulative health benefits from 2020 to 2050.