IDENTIFICATION OF A METHODOLOGY TO ESTIMATE VEHICLE EMISSIONS IN SRI LANKA

Abstract

Estimates available to date in Sri Lanka show that the transport sector is responsible formajority share of the gaseous emissions to the environment when compared to any othersector such ;IS industry. agriculture. and fisheries. This pattern is applicable to most of thecountries allover the world. Many countries have taken steps towards controlling vehicleemissions and Sri Lanka is seriously considering actions to control vehicle emissions.

In order to have an effective control system it is necessary to identify different emissionsand the significance of their effects to the environment and health. The main pollutantgases cmiucd from vehicles are Carbon dioxide. Nitrogen oxides. Carbon monoxide,volatile organic compounds and Sulfur oxides. As the effects and the significance couldchange from place to place and also depend on different concentration levels. it is veryimportant to estimate the emission to the environment to some accuracy

Numbers of different techniques have been used for the emission estimates. They includevery approxinuuc methods such as Iuc} sales to very sophisticated techniques such asremote scnsing measurements and simulation models. Whereas the simple techniquesrequire little base line dat;1 and cquipmcntx. more sophisticated techniques would requirecouxidcrahlc amount 01 base line information and equipment

The technique employed today in Sri Lanka is only a simple method h:iSC<1 on emissionLlclms. This quantification is done taking into account the emission factors roughlyestimated for each type of vehicle and on the total number or vehicles in the entire country.Only this can he used because of the difficulty faced in estimating the emission factors at aparticular time and because or the lack or use of basic data on vehicle transportation.From this technique the automobile emissions at a particular location at any given timecannot he estimated.

However automobile emissions will vary according to the age of the vehicle. its travelspeed and location. In order 10 incorporate these factors into the main csnmat ion basicdata on the 11I111Ihcorf vehicles at each place and their travel speeds have to he known.

The objective of this research is to identify a suitahle methodology incorporating theavailable data Oil traffic movement patterns to estimate vehicle emissions in Sri Lanka andto identity required development in the future to improve the estimating and monitoringprocedure. [11 this paper effects of different types of emissions. their significance andrelevance to the local conditions arc discussed. Methodologies available to measure andestimate selected types of emissions arc also discussed. Based on this knowledge anddepending on the technology and information available locally. a suitable procedure toestimate vehicle emissions that will he useful for any future control and monitoring isidem ificd.