Low emission zones (LEZs) are a regulatory measure in which access is restricted in a defined area for polluting vehicles (i.e. vehicles with higher emissions cannot enter the area or have to pay higher charges for access). The main driver of LEZs is to reduce air pollutant emissions; particularly those with the greatest health impacts, while co-benefits of this strategy include reduced CO2 emissions and stimulated growth of low emission vehicles.
- Action applies to both passenger and freight vehicles, but is likely to have greater implications for the latter due to generally lower emissions standards for high-duty vehicles (HDVs).
- Action applies generally to cars and trucks, but has potential for expansion to public transport vehicles as well.
- There would likely be no GHG emission benefits for most LEZ options; however, the introduction of Euro 4 vehicles could yield some carbon reductions.
- Research from London and Berlin indicates that the implementation of an LEZ could result in approximately 15% reduction in NOx and a 30% reduction in PM10. A proposed ultra-low emission zone (ULEZ) in London is expected to deliver a 51% reduction in NOx emissions, a 64% reduction in PM10 and a 15% reduction in CO2 emissions from road transport by 2020.
Status of deployment:
- The majority of global examples are concentrated in European cities, though the concept is being explored in China as well, and Hanoi is considering a general motorbike ban.