Estimating the greenhouse gas emission factor of motorcycles under real-world driving conditions in Hanoi: a case study

The lack of country-specific greenhouse gas (GHG) emission factors vehicles in Vietnam makes the emissions inventory in the transport sector more difficult. This study developed the country-specific GHG emission factor in terms of CO2 equivalent for motorcycles (MCs) in Hanoi to overcome the above impediment. The real-world driving data, instantaneous speed versus time, were collected on the 30 road routes in Hanoi using a GPS device. A filtering process of nine-step was designed to repair misleading speed values and denoise signals before entering the International Vehicle Emissions (IVE) model. The typical GHG emission factor for the MC fleet in Hanoi was approximately 90.83 g/km. This study also found a remarkable difference in the MC’s specific power-related bins distribution between the real-world driving characteristics of the MC in Hanoi and the ones of the World Motorcycle Test Cycle. This contributes to reconfirming the necessity of developing the GHG emission factor based on the very real-world driving data of Vietnam