Konara K.M.T.N.^1,, Samarasekara G.N.², Thushara Chaminda G.G³, Surendra Perera⁴

During last eight years’ total vehicle population in the country has been doubled according to the statistics of Department of motor traffic resulting in an increase of emissions. Road transportation have the highest vehicular emissions in terms of Greenhouse gases (GHG) in Sri Lanka. In a global perspective the emissions of multi modal vehicle fleet stand at 61%, 24%, 6%, 6% and 3% of GHG’s emits from buses, private vehicle, railways, para-transits and trucks respectively. According to the Sri Lankan department of motor traffic statistics, motor bicycles, motor tricycles and motor cars are the highly used vehicle types in Sri Lanka. In moving towards emission reduction through modal shifts to reduce, it is required to quantify the potential emission reduction gained through different modal shifts. Using the vehicle emission database, this research attempts to quantify emission reductions gained through different transportation strategies. All vehicle emissions were measured emissions per maximum seat occupancy in order to find per capita emissions in each vehicle category. It was found that motor bicycles (4.3% v/v per seat of CO₂ & 850 ppm per seat of HC) and motor tricycles (300% v/v per seat of CO) have the highest emission rates per passenger. Dual purpose vehicles (1.25% v/v per seat of CO₂) and buses were identified as the lowest emitters. Motor cars have slightly high emission levels comparative to buses. (350 ppm per seat of HC & 1.75% v/v per seat of CO₂). But still motor cars can be identified as a better mode than motor cycles and motor tricycles. Results of this study can be used to identify potential vehicle shifts which can be implemented to reduce emission growth in the country.

greenhouse gases, vehicle emissions, vehicle shifts