Authors:
In many regions of the world, older, high-emitting vehicles account for a small percentage of the overall vehicle fleet but a disproportionately large share of total emissions. It is estimated that these vehicles may be responsible for more than 50% of particulate matter (PM) and black carbon (BC) emissions by 2020.
This white paper examines how vehicle replacement, retrofit, and repower programs can have an immediate and positive environmental impact because they reduce emissions from older, gross emitting, and inefficient vehicles in the fleet within a short period of time. Positive environmental impacts can be achieved with the reduction of gaseous pollutants (CO, HC, NOX), as well as of particulate matter. Greenhouse gas (GHG) emissions are also reduced, especially of short-lived climate pollutants (SLCPs) such as black carbon, one of the main components of PM emissions.
The paper evaluates vehicle replacement programs worldwide and suggests five best practices that serve as guidelines for policymakers seeking to design and implement these programs in their jurisdictions.