Analysis of motorcycle fleet in Hanoi for estimation of air pollution emission and climate mitigation co-benefit of technology implementation

Abstract A fleet of over two million motorcycles (MC) in Hanoi is believed to contribute a substantial emission of air pollutants and climate forcers but has not been thoroughly characterized. This study conducted a survey of the MC technologies and activities in Hanoi using questionnaires, GPS monitoring, and video camera in 2008. The data were collected for three typical road types (highways, arterials, residential streets) in 3 zones of the city. Majority of MC in Hanoi were relatively new (3.6 years), had 4-stroke engine, but only 6% was equipped with catalyst exhaust control devices. About 35% of the fleet did not comply with any EURO standards. The MC daily driving was 20 km, mostly done on arterial streets. The main driving features in Hanoi arterials and residential streets were of low speeds with frequent starts/stops and idling. International Vehicle Emissions (IVE) model produced adjusted emission factors (EFs) that were compared with the limited available measurement data. The fleet emission was estimated for 2008 as a base case and for two “what-if” faster technology implementation scenarios: scenario 1 assumed that the entire fleet in 2008 conformed at least EURO2 and scenario 2 assumed 100% MC met the EURO3 standard. Total emissions from the fleet in 2008 of CO, VOC, NOx, SO2, PM10, and CH4 were 158, 51.5, 9.5, 0.17, 2.4 and 9.5 kt, respectively. Emissions of 1,3-butadiene, acetaldehydes, formaldehydes and benzene were 0.26, 1.2, 4.9 and 2.1 kt, respectively. Faster EURO3 technology intrusion in scenario 2 would significantly reduce the emission of pollutants (by 53–94%) and climate forcers in CO2-equivalent (53% for 20-year and 38% for 100-year horizon), which tripled the reductions obtained under scenario 1. Substantial co-benefits for air quality and climate forcer mitigation could be achieved by the faster technology implementation.