This study presents emissions of different pollutants from transport sector in Delhi. Results show that emissions of pollutants have increased during 2001-2009 as follows: CO2, 4395-6423; CH4, 1.03-3.32; N2O, 0.04-0.05; CO, 238-329; NOx, 44-64; and NMVOC, 44-60 Gg. However, CO2 emissions per unit of vehicle types for gasoline driven vehicles show a decrease as follows: two wheelers, 2.7; and cars, 4.3%; while in case of diesel driven vehicles, this reduction is 1.6%, indicating impact of better vehicle technologies introduced. However, CO2 emissions from per unit of CNG vehicles have been found to increase by 2.4% during this period due to increased consumption of CNG per unit of CNG vehicles

Sharma, Chhemendra

Singh, Richa

English

IR@NPL

155SINGH & SHARMA: ASSESSMENT OF EMISSIONS FROM TRANSPORT SECTOR IN DELHIJournal of Scientific & Industrial ResearchVol. 71, February 2012, pp. 155-160*Author for correspondenceE-mail: csharma@nplindia.orgAssessment of emissions from transport sector in DelhiRicha Singh and Chhemendra Sharma*Radio & Atmospheric Sciences Division, CSIR-National Physical Laboratory (NPL), New Delhi 110 012, IndiaReceived 05 July 2011; revised 15 December 2011; accepted 20 December 2011This study presents emissions of different pollutants from transport sector in Delhi. Results show that emissions ofpollutants have increased during 2001-2009 as follows: CO2, 4395-6423; CH4, 1.03-3.32; N2O, 0.04-0.05; CO, 238-329; NOx,44-64; and NMVOC, 44-60 Gg. However, CO2 emissions per unit of vehicle types for gasoline driven vehicles show a decreaseas follows: two wheelers, 2.7; and cars, 4.3%; while in case of diesel driven vehicles, this reduction is 1.6%, indicating impact ofbetter vehicle technologies introduced. However, CO2 emissions from per unit of CNG vehicles have been found to increase by2.4% during this period due to increased consumption of CNG per unit of CNG vehicles.Keywords: Activity data, Emission factor, Emission inventory, Greenhouse gases (GHGs), Transport sectorIntroductionIncreasing industrialization, urbanization andtransportation are the main causes of emissions ofGreenhouse gases (GHGs) and other air pollutants thatare responsible for deteriorated air quality and climatechange. Major pollutants emitted from transport sectorare carbon dioxide (CO2), methane (CH4), nitrous oxide(N2O), carbon monoxide (CO),  oxides of nitrogen (NOx),sulphur dioxide (SO2),  particulate matter (PM) and nonmethane volatile organic compounds (NMVOC).Transport sector has become one of the majoranthropogenic contributors of these air pollutants intoatmosphere1. These pollutants have significant adversehuman health effects in Asia 2. However, most of thehuman health impact assessments are based on the levelsof PM10 in the atmosphere in urban areas3.In India, Delhi is one of the most affluent urbancenters4 (area, 1483 km2; population, 16.75 million) andranked second among the most densely populatedmetropolitan cities5 after Mumbai (population density,9340 persons/ km2). Rapid urbanization and economicgrowth have resulted in increased consumption of fossilfuels and other natural resources, which are responsiblefor increased emissions of GHGs and other pollutants.In Delhi6, vehicles have been estimated to contributemaximum (67%) to the total pollution load, followed bypower plants (13%), industries (12%) and domesticsector (8%). Delhi itself accounts for about 8% of thetotal registered vehicles in India and has more registeredvehicles than those registered in other three metros(Mumbai, Kolkata and Chennai) taken together7. In Delhi,registered motor vehicles8, which were 3551690 units in2001, have increased to 6451883 units in 2009, registeringa growth rate of 81% (Fig. 1). Because of increasednumber of vehicles and consequent increasedconsumption of fuels in road transport sector in Delhi,emission of GHGs and other pollutants have alsoincreased significantly9 from 1990-91 to 1999 as follows:CO2 from gasoline driven vehicles, 766-1187; and CO2from diesel driven vehicles, 577-9779 Gg. In anotherstudy10 , CO2 emissions from transport sector hasincreased from 27% to 39% during 1999-2000 and NOx,CO and NMVOC emission contributed over 80% in totalemissions from transport sector as compared to thermalpower plant. For per unit area emissions of CO2, CO,CH4, HC, NOx, PM and SO2, Delhi has been estimatedat fourth place among five major metropolitan cities ofIndia (Chennai, Bangalore, Kolkata, Delhi andHyderabad)11. From a number of policy measuresimplemented in transport sector for improving Delhi’sair quality, reduction in sulfur content of diesel and petrol(gasoline) have helped to reduce SO2 emissions inDelhi12, and implementation of Euro-1 in 2000 has showed156 J SCI IND RES   VOL 71  FEBRUARY  2012the reduction in total emissions of CO, HC, NOx andVOCs for all the classes of vehicle 9 . Similarly, afterimplementation of compressed natural gas (CNG),decreasing trend was found in polycyclic aromatichydrocarbons (PAHs), SO2 and CO in ambient air, whileNOx level increased in comparison to that of pre CNGimplementation period13,14.This study presents emission inventories of differentpollutants from transport sector in Delhi, besidesassessment of CO2 emission efficiencies of differentvehicle types in Delhi during 2001-2009.Experimental SectionInventories for emissions of pollutants from transportsector can be computed on the basis of types of vehiclesand quantities of fuel consumed. Diesel is primarily usedin public passenger and cargo vehicles, while twowheelers and cars mainly use gasoline. In Delhi, most ofthe buses, omnibuses and taxies use CNG since 2001.An emission inventory for different pollutants emittedfrom transport sector has been prepared using IPCC2006 guidelines15 as E i = ADi * EFi, where Ei is emissionsof pollutant i, ADi is activity data of pollutant i and EFi isemission factor of pollutant i. Activity data (fuelconsumption and number of vehicles) for Delhi’stransport sector during 2001-2009 have been taken fromDelhi Government website (www.delhigovt.nic.in) andDelhi Statistical Handbook8 (Table 1). Default emissionfactors provided by IPCC16 were used for estimation ofemissions (Table 2).Table 1—Diesel and gasoline consumption in different categories of vehicles during 2001-2009  Years                            Diesel consumption, kt Gasoline consumption, ktTotal HCV/MCV LCV Total 2 Wheelers            Carsconsumption consumption  2001 764.2 534.9 229.2 569.5 341.7 227.8  2002 726.2 508.3 217.8 595.5 357.3 238.2  2003 773.1 541.2 231.9 610 366 244  2004 834.7 584.3 250.9 632.2 379.3 252.9  2005 823.0 576.1 246.9 666.7 400.0 266.7  2006 899.6 629.7 269.9 696.2 417.7 278.5  2007 963.9 674.7 289.1 737.5 442.5 295  2008 884.9 619.4 265.5 758.7 455.2 303.5  2009 787.5 551 236.2 795.7 477.4 318.3Fig. 1—Number of registered vehicles in Delhi during 2001-2009Years157SINGH & SHARMA: ASSESSMENT OF EMISSIONS FROM TRANSPORT SECTOR IN DELHIFor estimation of emissions from transport sector,there are two basic approaches (top-down & bottom-up)provided by IPCC guidelines. In top-down approach, totalconsumption of gasoline and diesel in transport sector isused, while in bottom-up approach, emissions areestimated using the fuel consumed in different kinds ofvehicles. In this study, top-down approach of IPCCmethodology has been used to estimate emissions fromtransport sector in Delhi. Using a reported17 approach toapportion fuel consumption, it is assumed that 70% ofthe total diesel sold has been consumed in road transportsector, out of which, 70% are consumed by medium andheavy-duty commercial vehicles (MCV/HCV) and therest 30% by light duty commercial vehicles (LCV).Similarly, for gasoline, it is assumed that out of the totalgasoline consumption, 60% is consumed by two wheelers(2W) and 40% by car/taxies17.ResultsVehicular Emissions in Delhi during 2001-2009GHGsFrom different vehicles, CO 2 (Fig. 2a), CH4(Fig. 2b) and N2O (Fig. 2c) emissions, respectively, haveincreased as follows: 2W, 1050-1467, 0.306-0.428, 0.009-0.013; cars, 700-978, 0.204-0.285, 0.006-0.009; HCV,1699-1751, 0.116-0.119, 0.013-0.014; and LCV, 728-750,0.050-0.051, 0.005-0.006 Gg.CO, NOx and NMVOCFrom different vehicles, CO (Fig. 2d), NOx (Fig.2e) and NMVOC (Fig. 2f) emissions, respectively, haveincreased as follows: 2W, 122-171, 9-12, 22.9-32.0; cars,81-114, 6.1-8.6, 15.3-21.4; HCV, 23-24, 18.5-19.1,4.6-4.8; and LCV, 9.9-10.0, 7.9-8.2, 1.9-2.0 Gg.Emissions from Consumption of CNGAfter introduction of CNG in Delhi’s transport sectoras replacement of diesel in public road transport, the fleetof CNG vehicles in Delhi has increased from 26350 unitsin 2001 to 344868 units in 2009, while CNG consumptionhas increased from 77.47 kt in 2001 to 526.98 kt in 2009.Emissions from CNG consumption during 2001-2009have increased as follows (Fig. 3): CO2, 216.85-1475.09;CH4, 0.359-2.44; N2O, 0.0004-0.0023; CO, 1.56-10.62;NOx, 2.34-15.94; and NMVOC, 0.019-0.133 Gg.DiscussionEmissions of CO2 increased by 46% during 2001-2009, while an earlier study9 showed a growth of 65%during 1990-91 to 1999-2000. During 2001-2009 fromthe transport sector in Delhi, increase in emissions ofother pollutants was found to be: CH4, 221; N2O, 25;CO, 38; NOx 46; and NMVOC, 34%. Emissions ofpollutants (CO2, NOx and N2O) are higher from dieseldriven vehicles as compared to gasoline driven vehicles.On the other hand, emissions of pollutants (CO, CH4and NMVOC) are higher from gasoline driven vehiclescompared to diesel driven vehicles. Pollutants’ emissionsfrom diesel driven vehicles (LCV & HCV) showeddecreasing trend post 2007 period. Emissions fromgasoline vehicles showed increasing trend due toincreased consumption. It indicates the preference forpersonalize mode of the transport over public transport.The increasing consumption of CNG shows preferencefor cleaner fuel in transport sector, which however, isalso responsible for estimated increase in CH4 emission(221%) during 2001-2009.Looking into trends of emissions per unit vehicletypes for different vehicles deduced for 2001-2009(Fig. 4), CO2 emissions showed negative compoundannual growth rate (CAGR) from cars (4.32%), 2W(2.71%), and diesel vehicles (1.63%), while CNG vehiclesshowed a positive CAGR (2.43%). Thus introduction ofbetter technologies in diesel and gasoline driven vehiclescurtailed pollutants emissions per unit vehicles, whichwould, otherwise, have been quite high due to increasingvehicle population and fuel consumption. Increase inemissions in CNG vehicles is probably because CNGconsumption has increased in greater proportioncompared to the increase in number of CNG drivenvehicles.Table 2—Carbon emission factor (CEF) and emission factors of other pollutants for different fuel types   Fuel CEF CH4 N2O CO NOx NMVOCtC/TJ kg/TJ kg/TJ kg/TJ kg/TJ kg/TJ  Diesel 20.2 5 0.6 1000 800 200Gasoline 18.9 20 0.6 8000 600 1500   CNG 15.3 92 0.1 400 600 5158 J SCI IND RES   VOL 71  FEBRUARY  2012Fig. 2—Pollutants’ emissions from different vehicles categories: a) CO2; b) CH4; c) N2O; d) CO; e) NOx; and f) NMVOCFig. 3—Pollutants’ emissions from CNG consumption: a) CO2; and b) CH4, N2O, NOx, CO & NMVOCYears Yearsa)b)Years YearsYears YearsYears YearsCO2, GgOther gases, GgNOx, GgCO2, GgCH4, GgCO, GgN2O, GgNMVOC, Ggb)a)d)c)f)e)4 2159SINGH & SHARMA: ASSESSMENT OF EMISSIONS FROM TRANSPORT SECTOR IN DELHIConclusionsThe number of vehicles in Delhi has registered agrowth of 81% during 2001-2009, resulting in increasedemissions of GHGs and other pollutants from transportsector. Diesel driven vehicles contributed more inemissions of CO2, NOx and N2O as compared to gasolinedriven vehicles in Delhi till 2007 but after that, emissionsfrom diesel driven vehicles showed reducing trend in 2008and 2009, because of decreased consumption of dieselin Delhi. Improvements in vehicle technologies seem tobe effective in curtailing emissions of pollutants as evidentfrom the reduction in emissions of CO2 per unit of vehiclesfor almost all categories of vehicles. However, increasingvehicle population is offsetting this reduction, resulting inthe increase in net emissions. CNG vehicles showedincreasing trend in per unit CO2 emissions due toincreased CNG consumption.AcknowledgmentsAuthors thank Prof R C Budhani, Director, NPL,New Delhi for constant encouragement and Dr B C Arya,Head, Radio & Atmospheric Sciences Division, NPL forsupport. Richa Singh is grateful to CSIR for fellowshipunder NWP-17 project.References1 Mitra A P, Global Change: Greenhouse Gas Emissions in Indiaupdate (National Physical Laboratory, New Delhi) 1992.2 Krupnick A & Harrington W, ESMAP Paper No.224 (The WorldBank, Washington, DC, USA) 2000.3 Dockery D W & Pope C A, Acute respiratory effects of Particu-late air pollution. Annu Rev Public Health, 15 (1994) 107-132.4 Census of India 2011, Provisional population Totals, NCT ofDelhi Series 8; (Website: www.censusindia.gov.in/2011-pro-re-sults/data_files/delhi/paper-1-2011 NCT of Delhi.pdf)5 w w w . e n . w i k i p e d i a . o r g / w i k ilist_of_most_populous_metropolitan_in_India6 MoEF 1997, White Paper on Pollution in Delhi With an ActionPlan (Ministry of Environment & Forest, Govt of India, NewDelhi) 1997.7 Status of the Vehicular Pollution Control Programme in India(Central Pollution Control Board, New Delhi, India) 2010.8 Delhi Statistical Handbook (Directorate of Economics & Statis-tics; Govt. of NCT, Delhi) 2010 (Website: www.delhigovt.nic.in).9 Sharma C & Pundir R, Inventory of green house gases and otherpollutants from the Transport sector: Delhi, Iranian J EnvironHealth Sci Engine, 5 (2008) 117-124.10 Gurjar B R, Aardenne Van J A, Lelieveld J & Mohan M, Emis-sion estimates and trends (1990-2000) for megacity Delhi andimplications, Atmos Environ, 38 (2004) 5663-5681.11 Ramachandra T V & Shwetmala, Emissions from India’s trans-port sector: State wise synthesis, Atmos Environ, 43 (2009)5510-5517.Fig. 4—CO2 emission efficiencies of different vehicles categories: a) 2 Wheelers; b) Cars; c) Diesel vehicles; and d) CNG vehiclesCO2, tYears YearsYearsYearsCO2, tCO2, tCO2, ta)d)c)b)160 J SCI IND RES   VOL 71  FEBRUARY  201212 Narain U & Krupnick A, The impact of Delhi’s CNG programon air quality: Discussion paper, Resour for the Future, 2007,1616 P St. NW, Washington, DC 20036 (Website: www.rff.org).13 Chelani A B & Devotta S, Air quality assessment in Delhi:Before and after CNG as fuel, Environ Monitor Assess, 125(2007) 257-263.14   Khaiwal R, Wauters E, Tyagi S K, Mor S & Grieken R V,Assessment of air quality after the implementation of com-pressed natural gas (CNG) as fuel in public transport in Delhi,India, Environ Monitor Assess, 115 (2008) 405-417.15  IPCC 2006, Guidelines for National Greenhouse Gas Invento-ries (website: www.ipcc.ch).16 IPCC EFDB, 2006 (Website: www.ipcc-nggip.iges.or.jp).17 Singh A, Gangopadhyay S, Nanda P K, Bhattacharya S, SharmaC et al, Trends of Greenhouse gases emissions from the roadtransport sector in India, Sci Total Environ, 390 (2008) 124-131.

Assessment of emissions from transport sector in Delhi

155-160This study presents
emissions of different pollutants from transport sector in Delhi. Results show that emissions of pollutants
have increased during 2001-2009 as follows: CO2, 4395-6423; CH4, 1.03-3.32;
N2O, 0.04-0.05; CO, 238-329; NOx, 44-64; and NMVOC, 44-60 Gg. However, CO2
emissions per unit of vehicle types for gasoline driven vehicles show a
decrease as follows: two wheelers, 2.7; and cars, 4.3%; while in case of diesel
driven vehicles, this reduction is 1.6%, indicating impact of

better vehicle technologies
introduced. However, CO2 emissions from per unit of CNG vehicles have been
found to increase by

2.4% during this period due
to increased consumption of CNG per unit of CNG vehicles

NOPR

http://npl.csircentral.net/3686/1/Assessment%20of%20emissions%20from%20transport.pdf

Assessment of emissions from transport sector in Delhi

Abstract

Similar works

Full text

Available Versions

IR@NPL

NOPR