414 a rDO 0~~~C .0. . ~~~~~~~~~~~ 0S Selected World Bank Titles on Air Quality World Bank Technical Papers No. 308 Faiz, Weaver, and Walsh, AirPollutionfrom Motor Vehicles: Standards and Technologiesfor Controlling Emissions No. 373 Onursal and Gautam, VehicularAir Pollution: Experiencesfrom Seven Latin American Urban Centers No. 377 Walsh and Shah, Clean Fuels forAsia: Technical Options for Moving toward Unleaded Gasoline and Low-Sulfur Diesel No. 378 Shah and Nagpal, eds., Urban Air Quality Management Strategy in Asia: Kathmandu Valley Report No. 381 Shah and Nagpal, eds., Urban Air Quality Management Strategy in Asia: Greater Mumbai Report No. 387 Oskarsson, Berglund, Seling, Snellman, Stenback, and Fritz, A Planner's Guide for Selecting Clean-Coal Technologies for Power Plants No. 391 Lovei and Weiss, Jr., Environmental Management and Institutions in OECD Countries: Lessons from Experience No. 397 Lovei, Phasing Out Leadfrom Gasoline: Worldwide Experience and Policy Implications No. 410 Sayeg, Successful Conversion to Unleaded Gasoline in Thailand No. 422 Quaak, Knoef, and Stassen, Energyfrom Biomass: A Review of Combustion and Gasification Technologies EnvironmentDepartment Papers No. 40 Lovei, Phasing Out Leadfrom Gasoline: World- Wide Experience and Policy implications No. 69 Schipper, Marie-Lillio, International Agency Paris, Transportation and C02 Emissions: Flexing the Link-A Path.for the World Bank No. 78 Lvovsky, Hughes, Maddison, Ostro, and Pearce, Environmental Costs of FossilFuels. A Rapid Assessment Method with Application to Six Cities Non-serialpublications Sebastian, Lvovsky, and de Koning, Decision Support System for Integrated Pollution Control: Software for Education andAnalysis in Pollution Management The World Bank Group in collaboration with the United Nations Environment Programme and the United Nations Industrial Development Organization, Pollution Prevention and Abatement Handbook 1998 Shah, Nagpal, Brandon, eds., Urban Air Quality Management Strategy in Asia: Guidebook Improving Urban Air Quality in South Asia by Reducing Emissions from Two-Stroke Engine Vehicles Masami Kojima Carter Brandon Jitendra Shah December 2000 WORLTHE BANK The International Bank for Reconstruction and Development/THE WORLD BANK 1818 H Street, N.W. Washington, D.C. 20433, U.S.A. Manufactured in the United States of America First Printing December 2000 The findings, interpretations, and conclusions expressed in this paper are entirely those of the author(s) and should not be attributed in any manner to the World Bank, to its affiliated organizations, or to member of its Board of executive Directors or the countries they represent. The World Bank does not guarantee the accuracy of the data included in this publication and accepts no responsibility for any consequence of their use. The bound- aries, colors, denominations and any other information shown on any map in this volume do not imply, on the part of the World Bank Group any judgment on the legal status of any territory, or any endorsement or accep- tance of such boundaries. Masami Kojima is a Senior Energy/Environment Specialist in the Oil, Gas, and Chemicals Department of the World Bank; Carter Brandon is a Lead Environmental Economist, and Jitendra Shah is a Senior Environmental Engineer, both of the South Asia Environment Unit of the World Bank. Cover: Traffic images of South Asia. All images property of the World Bank. Contents Foreword vii Abstract ix Acknowledgments ix Abbreviations xi Executive Summary 1 The Problem of Emissions from Two-Stroke Engine Vehicles 1 Emissionsfrom two-stroke engines pose a danger to public healthz 1 Poor vehicle mnintenance, mnisuse of lubricant, and adulteration of gasoline exacerbate emissions 2 Reducing Emissions from Two-Stroke Engines 2 Measures targeted at the existingfleet of twvo-stroke vehicles 2 Measures targeted at the environmnental performance of nezv tzwo-stroke vehicles 3 Replacing Two-Stroke Gasoline Engines 3 Four-stroke engines 3 Vehicles powered by liquefied petroleumlt gas 4 Vehicles powered by compressed natural gas 4 Electric vehicles 4 Standards and Enforcement 4 Chapter 1 Understanding the Problem of Two-Stroke Engine Emissions 7 The Role of Two- and Three-Wheel Vehicles in South Asia 8 Types of Emissions 9 Factors Exacerbating Emission 10 Misuse of lubricant 10 Inadequate vehicle maintenance 11 Adulteration of gasoline 11 Lack of catalytic converters 11 Health Impact of Emissions 12 Effect of Emissions on Global Warming 12 iii iv Improving Urban Air Quality in South Asia by Reducing Emissions from Two-Stroke Engine Vehicles Chapter 2 Reducing Emissions from Two-Stroke Engine Vehicles 13 Declines in Emissions 13 Improving Gasoline Quality 15 Improving Lubricant Use 15 Standards for lubricants 15 Using the correct concentration of lubricant 15 Using low-smoke lubricant 16 Metering lubricant 16 Improving Vehicle Design 16 Installing catalytic converters 17 Reducing scavenging losses 18 Improving Maintenance 18 Chapter 3 Alternatives to Two-Stroke Gasoline Engines 21 Four-Stroke Gasoline Engines 21 Vehicles Powered by Liquefied Petroleum Gas 22 Vehicles Powered by Compressed Natural Gas 22 Electric Vehicles 23 Chapter 4 Policy Options 25 Emission-Based Policies 25 Monitoring emissions 25 Repairing vehicles thatfail inspection 26 Technology-Specific Policies 26 Banning all two-stroke engines 27 More selective bans 28 Fiscal and Trade Policy Options 28 Tax incentives for vehicle renewal 28 Offering cash payments for older vehicles to remove them from the road 28 Ensuring adequate credit 29 Liberalizing trade in new vehicles 29 Public Education 29 Future Directions 29 Annex A Health Impact of Air Pollution 31 B Improving Particulate Sampling of Two-Stroke Engine Vehicles 35 C Analytical Tools for Cost-Benefit Analysis 39 D Reports Prepared under the South Asia Two-Stroke Engine Initiative 41 Notes 43 References and Selected Bibliography 45 Boxes 1 Reducing pollution while saving money 11 2 Emission standards from around the world 17 3 Reducing scavenging losses in two-stroke engines 19 4 Converting diesel three-wheelers to electric Tempos in Kathmandu 24 5 The role of the supreme court in air quality management in Delhi 27 6 Reducing emissions and improving performance through free inspection and maintenance clinics in Delhi 30 Contents v Figure 1 Number of vehicles in Delhi by type, 1971-96 7 Tables 1 Distribution of vehicles by type, selected South Asian countries 8 2 Emissions from uncontrolled motorcycles, 1970s (grams per kilometer except where otherwise indicated) 10 3 Emissions from selected Bangladeshi 2-stroke 3-wheelers (grams per kilometer) 10 4 Emission standards for gasoline-powered two-wheelers in Taiwan (China), 1988-2003 13 5 Emission standards for gasoline-powered two- and three-wheelers in India, 1991-2000 (grams per kilometer) 14 6 Particulate matter emission factors for two-wheelers in India 14 7 Relation between lubricant content and emissions by uncontrolled motorcycles 16 8 Retail prices of lubricants in India, March 2000 (Indian rupees) 16 9 Particulate matter emission factors for motorcycles in Bangkok (grams per kilometer, except where otherwise indicated) 17 10 Fuel economy of two-stroke and four-stroke engine vehicles 21 Al Experimental particulate emission results 36 Foreword ^ 6 ehicles are one of the dominant sources of ness and feasibility of enforcing different mitigation A. urban air pollution in South Asia. While this measures but also the socioeconomic implications > problem is common to growing metropoli- of those measures. We hope this report will stimu- tan areas throughout the world, it is particularly late the debate on these issues and help severe in South Asia, where over half of all vehicles policymakers arrive at informed decisions about are two- and three-wheel vehicles operating on two- how to tackle this source of urban air pollution. stroke engines. This report analyzes different technical and policy options for reducing emissions from two- Richard Ackermann stroke engines. As the study emphasizes, it is Director, Environment important to understand not only the cost-effective- South Asia Region vii Abstract hile vehicular air pollution is common ments are available. Two immediate simple solu- to growing metropolitan areas through tions-using the correct type and concentration of out the world, it is particularly severe lubricant and carrying out regular maintenance- in South Asia, where about half of all vehicles are would significantly reduce emissions from two- and three-wheel vehicles with two-stroke en- two-stroke engines while saving drivers money and gines. This report analyzes different technical and ultimately improving air quality. Promoting these policy options for reducing emissions from two- "win-win" measures requires building public aware- stroke engines. Precisely because two-stroke engine ness by disseminating information on the health vehicles are so numerous and popular, an policy impact of emissions; the types of engines, fuel, and decision to address emissions from these vehicles lubricant that reduce emissions; the importance of must take into account the socioeconomic conse- regular maintenance; and the advantages and disad- quences of such a decision. While a large-scale vantages of various measures for mitigating air immediate ban on gasoline-powered two-stroke pollution. Partnerships among government, industry, engine vehicles would be extremely difficult and and the public will continue to be crucial to bring about costly, numerous small and cost-effective improve- the changes required to achieve air quality goals. ix Acknowledgments his report summarizes the findings of the re Kingdom, and the joint UNDP/World Bank Energy gional Two-Stroke Engine Initiative carried Sector Management Assistance Programme out by the South Asia Environment Unit. (ESMAP). This initiative assessed the current state of pollu- The authors thank N. V. Iyer of the Society of tion from two-stroke engines and evaluated Indian Automobile Manufacturers and Bajaj Auto different policy and technology options for curbing Ltd. for his extensive comments and technical in- emissions from two- and three-wheel vehicles. puts. The report also benefited from constructive Masami Kojima of the World Bank's Oil, Gas, and comments by Maureen Cropper and Ken Gwilliam Chemicals Department (Global Products Group) of the World Bank. The authors thank the World and Carter Brandon and Jitendra Shah of the World Bank staff who prepared the background papers Bank's South Asia Environment Unit prepared this listed in annex D and would like to express their report under the guidance of Richard Ackermann, thanks to Barbara Karni for editorial assistance and Environment Director, South Asia Region. Funding James Cantrell for desktop publishing. The conclu- for this report, including for research and findings sions and recommendations of this report are solely referenced herein, has been provided by the Gov- those of the authors. ernments of Denmark, Norway, and the United xi Abbreviations API American Petroleum Institute ARAI Automotive Research Association of India CNG Compressed natural gas CVS Constant volume sampling ECE Economic Commission for Europe ESMAP joint UNDP/World Bank Energy Sector Management Assistance Programme FTP Federal test procedure (in the United States) IPIECA International Petroleum Industry Environmental Conservation Association ISO International Organization for Standardization JASO Japanese Standards Organization LPG Liquefied petroleum gas PM2.5 Particulate matter with an aerodynamic diameter of less than 2.5 microns PM10 Particulate matter with an aerodynamic diameter of less than 10 microns RON Research octane number SIAM Society of Indian Automobile Manufacturers UNDP United Nations Development Programme VAPIS Vehicular Air Pollution Information System xiii Executive Summary wo-stroke engine vehicles are ubiquitous major source of air pollution in South Asia. i in South Asian cities, where they consti- Because they are less expensive than other ve- 1. tute approximately half of the total vehicle hicles, two- and three-wheelers play an important population-60 percent in India-and contribute role in the transport market in South Asia and significantly to urban air pollution. The serious account for at least half of all vehicles in most health effects of this polluted air, breathed by 350 countries in the region. million people, make urban air quality manage- Two-wheel vehicles, which include mopeds, ment an important policy concern. This report scooters, and motorcycles, are used mostly for addresses the technical, economic, and policy personal transportation. Three-wheel vehicles, issues related to controlling air pollution from which include small taxis such as autorickshaws two-stroke engine vehicles. and larger vehicles that hold as many as a dozen In the past few years governments and vehicle passengers, are used commercially. Until this year, manufacturers in the region have started to nearly all three-wheelers and the majority of the address the two-stroke engine issue. India, which two-wheelers had two-stroke engines. Apart from has tightened its emissions control regulations, is emissions considerations, these two-stroke engine investing in improved monitoring and enforce- vehicles are much noisier than their four-stroke ment programs and has taken steps to improve equivalents-an issue that draws much attention lubricants used in two-stroke engines. Delhi has in South Asian cities, but is beyond the scope of provided financial incentives to owners to replace this paper. old three-wheel vehicles with new ones. Parallel to these government programs, two-stroke vehicle Emissionsfrom two-stroke engines pose a danger to manufacturers, aware that the regional market for public health these vehicles is under threat, have contributed to The most critical pollutant in South Asia in terms programs to improve vehicle maintenance and of public health impacts is fine particulate mat- have begun to bring alternative engine technolo- ter.n Fine particles have been shown in studies in a gies to the market. This report pulls together some number of cities around the world to have serious of the lessons learned to date across South Asia. health effects, including premature mortality and such nonfatal effects as respiratory symptoms, The Problem of Emissions from Two- exacerbation of asthma, and changes in lung Stroke Engine Vehicles function. Vehicle emissions of fine particles is Emissions from the large and rapidly growing particularly harmful because they occur near number of two- and three-wheel vehicles are a ground level, close to where people live and work. 1 2 Improving Urban Air Quality in South Asia by Reducing Emissionsfrom Two-Stroke Engine Vehicles Until recently new two-stroke engines emitted as much Finally, drivers are encouraged to buy too as an order of magnitude more particulate matter than much lubricant by the filling station operators four-stroke engines of similar size. When vehicle age, themselves, who earn higher margins on oil than maintenance, lubricant, and fuel quality are taken on petrol. Furthermore, adulteration of gasoline into account, two-stroke engines in South Asia with kerosene is widespread in some countries in probably emit particulate matter at an even higher South Asia because of the large difference in the factor. retail price of the two fuels. This practice increases Two-stroke engines typically have a lower fuel emissions because kerosene has a higher boiling efficiency than four-stroke engines, with as much point than gasoline and is therefore more difficult as 15-40 percent of the fuel-air mixture escaping to burn. As a result more deposits build up in the from the engine through the exhaust port. These engine and damage the engine over time, and "scavenging losses" contain a high level of more unburned hydrocarbons are emitted in the unburned gasoline and lubricant, which increases exhaust gas. emissions of hydrocarbons and organic lead if gasoline is still leaded.2 Some of the incompletely Reducing Emissions from Two-Stroke burned lubricant and heavier portions of gasoline Engines are emitted as small oil droplets, which in turn Emissions from the existingfleet of two-stroke increase visible smoke and particulate emissions. gasoline engines can be reduced by (a) ensuring that drivers use the correct type and quantity of Poor vehicle maintenance, misuse of lubricant, and lubricant, (b) improving vehicle maintenance, and adulteration of gasoline exacerbate emissions (c) improving the quality of gasoline. For new vehicles, emissions can be reduced by (d) redesign- T he age and poor maintenance of many two- and intosrkennstodcaesaenn three-wheelers in the region increase emissions mg two-stroke engmes to decrease scavengmg losses and the amount of lubricant needed, and well above any applicable standards. In addition, lseanthamutolbrctned,ad well abovers any applicableof standard. Iuaditin, (e) installing catalytic converters to further reduce meadiny driv use lubrincant oftrela proorbali tailpipe emissions. Some of these measures can be leading to two distinct but related problems: ahee hog euain tesrqiems • Man drivrs inSout Asiause wdelyachieved through regulation. Others require mass anyilable dtraiver mineSouth Asiaor usewieducation of drivers, vehicle owners, regulators, availabled foustraigt miner oil oratnewor thanth and even the public, which has a role in bringing recycled four-stroke engine oil rather than the poiia prsuet.er ntepolm specially formulated 2T oil recommended by vehicle manufacturers. These oils build up in Measures targeted at the existingfleet of two- the engine, increasing emissions. stroke vehicles * Drivers also use excessive quantities of Ensuring that drivers use the correct type and quantity lubricant. Some drivers may simply lack of lubricant. In much of South Asia very few knowledge about the correct amount of drivers of commercial three-wheelers use 2T oil. lubricant to add and the adverse effects of In Bangladesh the use of excessive amounts of using too much. Others believe that adding straight mineral oil is the norm rather than the extra lubricant increases fuel economy and exception among three-wheeler drivers. The sale provides greater protection against piston of straight mineral oil for use in vehicles is not seizure. To the extent that straight mineral oil illegal. Changing the behavior of these drivers to may not mix with gasoline as well as 2T oil, a use the correct quantity of 2T oil, as well as greater quantity of lubricant is needed for raising the standards for the type of lubricant that lubrication. In reality this practice provides must be used, would make an enormous differ- little or no benefit to drivers, but significantly ence in particulate emission levels. Preliminary increases the level of emissions and reduces the tests show that reductions of particulate matter quality of air for society at large. emissions of as much as two-thirds may be Executive Summary 3 achieved through the use of the proper amounts designing better port configurations. In India, for of higher quality lubricants.3 example, short-circuiting fuel losses have been At the technical level, metering the correct reduced from 35 to 14 percent as a result of better amount of lubricant directly into gasoline at the engine designs. Several new technologies for pump (the so-called premix in India) is one way reducing scavenging losses are also being tested, of ensuring that the correct type and quantity of but all of these would require an electronic engine lubricant is used. Banning the sale of "loose" oil in management system. While this system would favor of the sale of premeasured sealed packets add to the cost of the vehicle, this cost would be would also help enforce adding the right amount partially offset by improved fuel efficiency. at the petrol pump. The use of higher-quality 2T oil Installing catalytic converters. Installation of represents cost savings to nmost two-stroke vehicle catalytic converters in two- and three-wheelers drivers. Even though the oil itself is more expen- would reduce exhaust emissions by about half. sive, analysis has repeatedly shown that 2T oil Vehicles with catalytic converters must use lead- used in the proper amount costs less than drivers free gasoline, however, which is not widely currently pay for larger amounts of lower-grade available in some parts of South Asia. The dura- oils. In addition come nonquantified benefits of bility of catalytic converters for two-stroke longer engine life and lower emissions. engines is also an issue. For commercial three- Improving vehicle maintenance. The importance wheelers catalysts are likely to have to be replaced of an effective inspection and maintenance at intervals ranging from six months to a year to program cannot be overemphasized: proper maintain reasonable emission levels. While maintenance is critical to both increasing fuel essentially no data are available to quantify the efficiency and reaping the full benefits of emission impact of catalytic converters on reducing par- reduction investments. Simple servicing proce- ticulate emissions from two-stroke engines, dures-cleaning and adjusting the carburetor, estimates indicate that cost-effectiveness may be adjusting the ignition system, cleaning and questionable. adjusting or replacing spark plugs, and cleaning air filters-can reduce exhaust emission levels Replacing Two-Stroke Gasoline Engines significantly as well as improve fuel efficiency. In addition to reducing emissions from two-stroke Tying the frequency of inspection to the age of the gasoline engines, both governments and vehicle vehicle and the annual number of kilometers manufacturers are finding cleaner alternatives to traveled could also increase the effectiveness of these engines. Options include four-stroke gaso- inspection programs. line engines and engines powered by liquefied Improving the quality of gasoline. Eliminating the petroleum gas, compressed natural gas, and widespread practice of adulterating gasoline with electricity. As cleaner vehicles come on the kerosene would reduce emissions. Reducing the market, the share of the older, more polluting gum content and increasing the octane level of vehicles will fall. In addition, retrofit kits that take gasoline that does not meet the minimum speci- advantage of cleaner fuels and lubricants are fied by vehicle manufacturers could also cut becoming increasingly available for installation on emissions. High gum content can cause an engine older two-stroke engine vehicles. to misfire, damaging the vehicle and significantly increasing emissions of hydrocarbons and particu- Four-stroke engines late matter. Low octane can cause knocking and Replacing two-stroke engines with four-stroke engine malfunction. engines (at the time of vehicle replacement) would significantly reduce hydrocarbon and Measures targeted at the environmental priuaeeisos lhuheisoso performance of new two-stroke vehicles particulate emissions, although emissions of nitrogen oxides would increase. Red ucing scavenging losses. Substantial reductions The cost difference between new two- and in scavenging losses have been achieved by four-stroke engines is less than 10 percent. If 4 Improving Urbanz Air Quality in South Asia by Reducing Emissions-from Twvo-Stroke Engine Vehicles operating and maintenance costs are taken into powered vehicles depends on the local retail price account-especially the 10-20 percent improved of natural gas. Switching to natural gas would fuel efficiency over the life of the vehicle-owning make economic sense only if the retail price of afour-stroke engine vehicle may be more economical CNG were about 55-65 percent of the cost of the than owning a two-stroke engine vehicle. If the social fuel being replaced. Without consistently lower benefits of reduced emissions are factored in, the gas prices, promotion of CNG-powered vehicles net economic benefits are even higher. The may not be sustainable. negative socioeconomic effects of banning new Governments have a disincentive to reduce the two-stroke engines are small. price of CNG, however, since a consumer shift from (taxed) fuels to (essentially untaxed) CNG Vehicles powered by liquefied petroleum gas would reduce their tax revenues. In countries Two-stroke engines powered by liquefied petro- such as India that will soon begin importing leum gas (LPG) typically produce lower levels of liquefied natural gas on a large scale as a future particulate emissions than two-stroke gasoline source of natural gas, world crude prices could particulate emissions than two-stroke gasoline make it difficult to keep CNG prices much lower engines. Moreover, since lubricant cannot bemaeidficltokpCNpresuhlwr penines. Moreover, si lustbrc mechannotlbe than gasoline prices. Bangladesh, however, with premixed with ng t mustbe m a lits large natural gas reserves and extensive meterbreimationg Them prosiblesit of networks of gas pipelines in large cities, might be overlubrication. The main problems in introduc- abet nrdc N notetasotsco ing LPG into the transport sector in South Asia are withou comrod miing othetranespin tec the lack of sufficient domestic sources of supply economy. and the inadequate distribution system. India, Pakistan, and Sri Lanka import about 30-40 Electric vehicles percent of their LPG consumption. None of the countries in the region has made the necessary Electric three-wheel vehicles are estimated to cost investments in LPG refueling stations, the lack of nearly twice as much as gasoline-powered ve- which constrains widespread LPG use. In fact, the hiles (based on market prices in India), have use of LPG in vehicles is illegal in India and Sri shorter ranges, and run on batteries that take up Lanka today, although this situation is expected to to 6-10 hours to recharge. Until technological change in the near future. changes make these vehicles more attractive, they are not expected to play an important role in Vehicles powered by compressed natural gas South Asia except in extremely polluted traffic corridors. In Kathmandu, Nepal, for example, Compressed natural gas (CNG) is a potentially large electric three-wheelers known as Tempos attractive fuel because it emits little particulate have proved very popular with the government matter, volatile organic compounds, or sulfur and passengers. In early 2000 about 500 of these oxides when burned. Bangladesh and Pakistan are vehicles were operating in Kathmandu, partly in piloting the use of CNG. Bajaj Auto in India has response to the ban on diesel Tempos imposed by developed CNG-powered three-wheelers based the government in 1999. on a four-stroke engine design and began to market these in 2000. Standards and Enforcement Although replacing two-stroke gasoline Emission-based standards tend to be more cost- engines with vehicles powered by CNG would effective than policies that dictate specific reduce emissions, providing substantial subsidies technologies. But enforcing emission standards to promote such vehicles is not recommended. As requires effective inspection and maintenance New Zealand's unsuccessful promotion program programs. Policymakers can deal with pollution shows,4 adoption of CNG as an alternative fuel by setting emission targets that vehicles must must be based on economic viability, not artificial meet or by mandating specific types of fuel or inducements. The economic viability of CNG- vehicle technology in the hope of achieving Executive Summary 5 emission targets. Emission-based measures agitation. Moreover, banning existing two-stroke provide greater flexibility to suppliers of fuels and engines without putting in place a well-docu- vehicles, who can choose the lowest-cost options mented vehicle registration system, an effective for meeting the specified emission targets. Pro- traffic police force, and transport alternatives for vided people comply with emission-based the current users could lead to increased harass- standards-and unfortunately their monitoring ment of drivers and corruption by traffic police. may be more difficult than that of technology- More viable options are to: (a) ban older (and based measures-they generally represent a typically more polluting) two-stroke vehicles from lower-cost option for society as a whole. urban areas; (b) raise annual registration fees for Regulations based on fuel and vehicle tech- older vehicles to incorporate environment-related nologies mandate the minimum technology to factors as well as vehicle book value; and/or (c) adopt. Such measures include banning two-stroke ban new two-stroke engine vehicles. The first two engines, mandating the use of catalytic converters, approaches seek to encourage the removal of and requiring that a percentage of vehicles run on older and more polluting vehicles from polluted gaseous fuels. This approach is not likely to be a cities, either through their being scrapped or low-cost solution unless rigorous cost-benefit relocated to less populated areas. analysis is performed to identify the optimal These options are best pursued if the following technologies for each specific situation. conditions are met: (i) alternatives to the vehicles At the heart of the policy debate concerning being removed are readily available and market- controlling emissions from new two- and three- tested; (ii) these alternatives are affordable, which wheelers is the level of emission limits, because may require the lowering or elimination of import the emission standards in turn may dictate the duties or other taxes on new vehicles; and (iii) choice of vehicle technology and even fuels. sufficient credit exists for vehicle owners and Taiwan (China) will effectively ban new two- drivers to be able to finance the purchase of the stroke engine motorcycles in 2003 by making newer vehicles. In assessing each of these mea- emission standards so tight that only four-stroke sures, policymakers need to weigh the engine motorcycles can meet them.5 The emission socioeconomic cost of making it more expensive standards that came into effect in 2000 in India to own old vehicles against the public health can be met by two-stroke engine vehicles only if benefits of reducing vehicular emissions. oxidation catalysts are installed. The result is an In sum, two immediate simple solutions could increasing move toward four-stroke engine two- significantly improve air quality. Using the correct and three-wheelers, although for very small type and concentration of lubricant and carrying engines (for example, 50 cubic centimeters), two- out regular maintenance would significantly stroke engines will remain the technology of reduce emissions from two-stroke engines while choice in the foreseeable future. potentially saving drivers money. Promoting these Banning all two-stroke engines is not the answer. "win-win" measures requires building public Banning all existing two-stroke engines in urban awareness by disseminating information on the areas would reduce emissions but eliminate point- health impact of emissions; the types of engines, to-point transportation for millions of South fuel, and lubricant that reduce emissions; the Asians. Women and families, who depend on the importance of regular maintenance; and the vehicles more than other groups, and the many advantages and disadvantages of various mea- people who use the vehicles commercially would sures to mitigate air pollution. In South Asia be particularly hard hit by a ban. Taking two- partnerships among government, industry, and stroke three-wheelers off the road in a precipitous the public will continue to be crucial to bringing manner would also affect the livelihoods of tens about the changes required to achieve air quality of thousands of drivers and invite widespread goals. CHAPTER 1 Understanding the Problem of Two-Stroke Engine Emissions ir quality is deteriorating in the cities of India the number of registered vehicles tripled in South Asia and is a byproduct of rapid 10 years from 10.6 million in 1986 to 33.6 million urban population growth. Of the 1.3 in 1996, an annual average rate of growth of more billion people living in Bangladesh, Bhutan, India, than 12 percent (figure 1). The number of vehicles Nepal, Pakistan, and Sri Lanka in 1998, 350 mipal,o- Percetant ofd the combined populatio grew rapidly in other countries in the region as milliofnth cou centries-liv combined inpura .th n well, increasing at an annual rate of 8.2 percent in of these countries-lived in urban areas. The average population growth in urban centers, 3.2 Bangladesh (1990-96), 13.5 percent in Nepal percent a year between 1990 and 1998, was much (1990-99), 8.0 percent in Pakistan (1990-99), and higher than the 1.3 percent rate of growth for the 7.3 percent in Sri Lanka (1990-97). In the absence population as whole. of cleaner technologies and stringent control A major source of air pollution is emissions measures, the level of vehicular emissions is from the rapidly rising number of vehicles. In expected to increase at similarly high rates. Figure I Number of vehicles in Delhi by type, 1971-96 3,000 | Goods !vehWdes 2,500 * Buses j2,000 0 Taxi OO 3-wheelers 1,500 Z 2-wheelers 0 1,000 ES Carsljeeps/ station 500 wgn 0 _ LM U Iv 0. ln rI e - Ln I- o- t... tW r-. 0 o 0 0 0o Cy _ _ _ _ _ _ _ _ _ _ _ __. 0. 0. 0. 0. 0. 0. 0. 0. 7 8 Improving Urban AirQualityin SouthAsia byReducingEmissions from Tvo-StrokeEngine Vehicdes The Role of Two- and Three-Wheel Because they are used commercially, three- Vehicles in South Asia wheelers are driven much more than Two-stroke engine vehicles in South Asia fall into two-wheelers and require frequent maintenance. two categories, two-wheelers and three-wheelers. But drivers often fail to maintain their vehicles Two-wheelers include mopeds, scooters, and properly. The problem of maintenance is particu- motorcycles and are used mostly for personal larly severe when drivers lease their vehicles, transportation. Three-wheelers include small taxis because neither the driver nor the owner feels such as autorickshaws and larger vehicles such as solely responsible for the mechanical condition of Tempos in Bangladesh and Nepal, which carry as the vehicle. many as a dozen passengers. Three-wheel taxis are perceived as less compli- Two- and three-wheelers play an important ant with traffic regulations and more accident role in the transport market in South Asia. India prone than four-wheel vehicles. They are also has a very large number of two-wheelers, which more visible, because of their numbers, and are used for personal transport. Three-wheelers contribute to congestion. For these reasons there is (called baby taxis in Bangladesh and strong sentiment in some countries, notably autorickshaws in India and elsewhere) are typi- Bangladesh, against two-stroke engine three- cally used as short-distance taxis. In Sri Lanka wheelers. some families are buying three-wheelers for Two-stroke gasoline engine vehicles are private use, attracted by the lower price of the estimated to account for about 60 percent of the vehicles relative to passenger cars. total vehicle fleet in South Asia (table 1). The large Table I Distribution of vehicles by type, selected South Asian countries Bangladesh India Nepal Pakistan Sri Lanka Vehicle type (1999) (1997) (1999) (1999) (1997) Cars 92,000 3,500,000 49,000 670,000 122,000 Taxis 2,300 420,000 - 68,000 6,000 Light-duty gasoline 52,000 740,000 2,600 310,000 14,000 Heavy-duty diesel 55,000 5,200,000 46,000 750,000 235,000O Two -stroke three- 68,000b 1,180,000 - 91,000 59,000 wheelers Four-stroke three- 7,600b 210,000 5,900c - - wheelers Two -stroke two- 200,OOOd 21 ,800,000 1 1 0,000d 1 ,700,000d 424,00 wheelers Four-stroke two- 35,OOOd 3,900,000d I 9,000d 250,OOOd 75,OOOd wheelers Total 523,000 37,200,000 232,000 4,000,000 936,000 Percentage of two- 51 62 47 45 52 stroke vehicles - Not available. Note: Because vehicle registration is by vehicle category and not by fuel type, these figures are based on assumptions about fuel use by each vehicle category. Breakdowns should therefore be taken as approximations. Totals may exceed the sum of the individual categories because of other categories not listed, such as tractors. a. All diesel vehicles except diesel cars. b. Ninety percent of three-wheelers are assumed to be two-stroke engine vehicles. c. The total number of three-wheelers in Nepal is 5,900. No estimates could be made of the breakdown of three-wheelers because of the large number of four-stroke engine diesel three-wheelers. d. Eighty-five percent of two-wheelers are assumed to be two-stroke engine vehicles. Source: Bangladesh Road Transport Authority; Society of Indian Automobile Manufacturers; Department of Transport Manage- ment, Kathmandu, Nepal; Economic Adviser's Wing and Economic Survey, Government of Pakistan; Ministry of Transport and Highways, Sri Lanka. Understanding theProblem of Two-StrokeEngineEmissions 9 number of these vehicles, their age, poor mainte- losses," which can amount to 15-40 percent of the nance, low lubricant quality and excessive unburned fresh charge, the exhaust contains a lubricant use, and traffic congestion in large cities high level of unburned fuel and lubricant (MECA make two-stroke engine vehicles a significant 1999). Nitrogen oxide emissions tend to be lower source of particulate emissions. because a significant portion of the combustion Two-stroke engines have several advantages products remains in the cylinder. over four-stroke engines. These include lower In two-stroke engines the crankcase is not used cost; excellent torque and power; mechanical as an oil reservoir, as it is in four-stroke engines. simplicity (fewer moving parts and resulting ease Instead a small amount of lubricating oil is added of maintenance); lighter and smaller engines; to the fuel or introduced continuously mechani- greater operating smoothness; and lower nitrogen cally. Because lubrication is on a total loss oxide emissions. They also have disadvantages (once-through) basis, incompletely combusted compared with four-stroke gasoline engine lubricant and other heavy hydrocarbons are vehicles, including higher particulate and hydro- emitted as small oil droplets. These oil droplets carbon emissions, lower fuel economy, and louder increase visible smoke and particulate emissions, noise.6 with serious impact on public health because of their well-documented link to morbidity and Types of Emissions premature mortality (annex A). Gasoline engines contribute to air pollution by Particulate emissions data from two-stroke emitting high levels of particulate matter (in the engine vehicles in South Asia are scarce. Data on case of two-stroke engines), lead if leaded gaso- motorcycles in the United States from the 1970s line is used, carbon monoxide, nitrogen oxides, may be representative of pre-1991 two-stroke and volatile organic compounds. Diesel engines engine vehicles in South Asia (table 2). More emit hightlevels ofparticulate matter, nitrgenne recent data (table 3), from tests done in the fall of emit high levels of particulate matter, nitrogen 2000 at ARAI (the Automotive Research Associa- oxides, and sulfur oxides (if the level of sulfur in tion of India), indicate that particulate emissions Tdiesel iS high) . levels of in-use three-wheelers from Dhaka (engine The pollato spe cncern in hia size of 150 cubic centimeters) are significantly is sallpartculte atte beaus of ts ighhigher than the data obtained in the 1970s. These ambient concentrations and documented impact testsal that 7-yed vehes using on morbidity and premature mortality. The level tests also show that 7-year old vehicles usmg of particulated matterwit h and p t remodnamit. d - lexcess "straight mineral oil" emit particulate of particulate matter with an aerodynamic diam- matter up to ten times, and that 4-year old ve- eter of less than 10 microns (PM10) exceeds hicles using "straight mineral oil" emit particulate internationally accepted standards by several matter roughly two to three times, the typical times in a number of cities in South Asia. Two values obtained in the United States in the 1970s. major contributors to high ambient concentrations For both ages of vehicles, particulate emissions of PMIO in the transport sector are two-stroke are much less if the correct amount of 2T oil, engine gasoline vehicles and heavy duty diesel formulated specifically for use in two-stroke vehicles. engine vehicles, is used. Emissions are higher in two-stroke engines Since two-stroke engine vehicles emit signifi- because of the design of the engine. Gas is ex- cantly more unburned gasoline than four-stroke changed through ports located in the cylinder, engines, they emit more organic lead if leaded usually opposite each other. A fresh fuel and air gasoline is used.7 Organic lead is much more mixture compressed in the crankcase enters damaging to public health than inorganic lead through the intake opening, while exhaust gases formed by combustion of lead additives. Lead exit through the exhaust port. While both the emissions are a problem in countries such as intake and exhaust ports are open some of the Pakistan that still sell only leaded gasoline. fresh fuel and air mixture escapes through the Fortunately, Bangladesh phased lead out of exhaust port. As a result of these "scavenging gasoline in July 1999, India in February 2000, and 10 Improving Lrban Air Qualityin South Asia byReducingEmLssionsfrom Two-Stroke Engine Vehicdes Table 2 Emissions from uncontrolled motorcycles, 1970s (grams per kilometer except where otherwise indicated) Engine size (cubic Carbon Oxides of Particulate Model Type centimeters) Hydrocarbons monoxide nitrogen matter Honda SL I OOa Four-stroke 100 1.3 13.7 0.21 0.02 Honda CL350K3a Four-stroke 350 2.5 28.9 0.03 0.03 Kawasaki 125F-6a Two-stroke 125 6.1 4.8 0.10 0.12 Suzuki T250a Two -stroke 250 12.9 21.6 0.02 0.35 Yamaha DT I Ea Two -stroke 250 10.3 16.3 0.03 0.15 Kawasaki KEIOOb Two-stroke 100 5.6 20.5 - 0.34 Yamaha DTI00b Two-stroke 100 3.8 10.5 - 0.08 - Not available. Note: Uncontrolled vehicles are those with no emissions control measures. Source: a. Southwest Research Institute 1973; b. Danielson 1975. Table 3 Emissions from selected Bangladeshi two-stroke three-wheelers (grams per kilometer) Lubricant Percentage Carbon Oxides of Particulate Vehicle age type lubricant Hydrocarbons monoxide nitrogen matter 7 years straight 8% 23 25 0.03 2.7 7 yearsa 2T 3% 16 17 0.09 0.9 4 years straight 8% 9 8 0.08 0.6 4 years 2T 3% 9 10 0.09 0.2 Note: a. Data taken after performing simple maintenance procedures on the vehicle. Source: ARAI (Automotive Research Association of India), November 2000. These measurements are preliminary and require further analysis. Pakistan and Sri Lanka are considering strategies lubricant for two-wheelers and 3 percent lubricant for eliminating lead in gasoline. for three-wheelers. But many drivers of three- wheelers add considerably more lubricant for Factors Exacerbating Emission several reasons: Poor vehicle maintenance, the misuse of lubricant, * Lack of knowledge about the correct amount to the adulteration of gasoline, and the lack of add catalytic converters exacerbate two-stroke engine * Lack of knowledge about the adverse effects of emissions. The age and poor maintenance of excess lubricant many two- and three-wheelers in the region . A increase emissions well above any applicable fillin station attendants at the point of sale standards. In addition, many drivers use lubri- cants and fuels of poor quality. * Perception that more lubricant will provide greater protection against piston seizure Misuse oflubricant * Perception that more lubricant will increase Both the quantity and quality of lubricant used fuel economy affect the level of hydrocarbon and particulate * Lower miscibility of straight mineral oil and emissions from two-stroke engines. Vehicle conventional motor oils with gasoline manufacturers recommend adding 2 percent compared to 2T oil. Understanding the Problem of Two-StrokeEngneEmissions 11 Excessive use of lubricant increases combus- results in insufficient lubrication when oil does tion chamber deposits and fouls spark plugs. not reach the engine and high emissions when it When pistons and rings are badly worn, excess does. Long-term use of conventional lubricants lubricant may postpone piston seizure for a while. results in premature wear of the engine and But the adverse social effects of much higher higher maintenance costs. emissions far outweigh the benefits to vehicle owners. Inadequate vehiclemaintenance Lubricant requirements for two-stroke engines Vehicular emissions are exacerbated by the age of differ from those for four-stroke gasoline engines: the vehicle fleet and the poor state of vehicle good lubricity; piston cleanliness; low deposits, maintenance (ARAI, 1998). A study in the United especially in the exhaust system; and low smoke States found that poorly maintained vehicles, emission. Two-stroke engine vehicles should use which represented 20 percent of all vehicles on the specially formulated 2T oil. Because road, contributed about 80 percent of total vehicu- polyisobutene of moderate molecular weight lar emissions (Auto / Oil Air Quality Improvement tends to decompose without leaving heavy Research Program 1997). Recently three baby taxis deposits, polyisobutene thickener in a base stock in Dhaka, Bangladesh, from four to seven years is increasingly used in lubricant. Japan has taken old were randomly selected for mechanical the lead in developing new motorcycle oils inspection. The engineers inspecting the engines referred to as low-smoke or smokeless lubricants. found evidence of considerable ad hoc, unautho- Many three-wheelers in South Asia do not use rized repairs and modifications. A combination of the 2T oil recommended by vehicle manufactur- inadequate or improper maintenance and repairs ers. Instead they use straight mineral oil or new or by poorly trained mechanics contributes to the recycled engine oil, which results in greater poor mechanical state of many vehicles in South deposit buildup and higher emissions (box 1). The Asia. principal reason for using these oils is their lower cost, although some drivers may be under the Adulteration ofgasoline impression that these more viscous oils provide greater engine protection. In some countries, such Emissions by all gasoline vehicles are exacerbated as Bangladesh and Sri Lanka, 2T oil is not readily by the adulteration of gasoline with kerosene. available at filling stations. Kerosene has a higher boiling point than gasoline Conventional motor oils do not mix well with and is thus more difficult to burn. As a result gasoline. Their use in two-stroke engine vehicles more deposits build up in the engine and more unburned hydrocarbons are emitted in the - - exhaust gas. Anecdotal evidence suggests that Box I adulteration of gasoline is widespread in South Reducing pollution while saving money Asia because of the significantly lower retail price Many drivers in Bangladesh use mineral oil instead of kerosene. Limited sampling and testing of of 2T oil because it is less expensive. But switching gasoline by the World Bank in Dhaka in 1998 also to 2T oil would actually save most drivers money. indicated that a significant fraction of gasoline Straight mineral oil in Dhaka sells for about 50 takas had been adulterated a liter, while 2T oil sells for about 90 takas a liter. A driver of a baby taxi who uses 6 liters of gasoline a day and drives 280 days a year would typically Lack of catalytic con verters spend 6,700 takas a year adding straight mineral oil at 8 percent concentration. A driver who switched Catalytc converters-istalled i passenger cars to a 3 percent concentration of 2T oil would spend in many parts of the world where unleaded just 4,500 takas a year-an annual savings of 2,200 gasoline is readily available-cannot be used to takas. The switch to 2T oil would also reduce emis- convert a high proportion of hydrocarbons in two- sions and help maintain vehicles. stroke engines because current designs result in Source:Informal World Bank survey, 1999. greater exotherm (heat of reaction) and the 12 Improving Urban Air Qualitvin South Asia byRedudngEnissions from Two-Stroke Engine Vehicles sintering of precious metals, which deactivates the particles or PM10, not against vehicular particu- catalyst. The tendency of two-stroke engines to late emissions. Most of the particulate matter from misfire under low load conditions further aggra- two-stroke engines is soluble organic matter, vates the problem of catalyst deactivation. Despite whereas particulate matter from diesel vehicles these limitations oxidation catalysts-which lower and stationary sources contains a significant the emission levels of hydrocarbons and carbon amount of graphitic carbon. Their behavior in the monoxide and to some extent reduce the amount atmosphere in terms of nucleation, agglomeration, of fine particles emitted in the form of oil drop- dispersion, and condensation could be quite lets-have been used in Taiwan (China) to meet different. This area of research merits further increasingly tight emission standards. Beginning investigation. in 2000 these converters are installed in all new two-stroke engine two- and three-wheel vehicles Effect of Emissions on Global Warming in India. Three greenhouse gases emitted by vehicles- carbon dioxide, methane, and nitrous oxide-are Health Impact of Emissions believed to have the potential to increase global Research in various cities and countries has warming. Two-stroke engines are not a major shown that PM10, and especially PM2.5 (particles source of these emissions, however. The transport with diameters of no more than 2.5 microns, sector accounts for an estimated 13 percent of called fine particulate matter), are extremely carbon dioxide emissions in South Asia, ranging damaging to public health. These particles are from 10 percent in Bangladesh to 48 percent in Sri associated with respiratory symptoms, exacerba- Lanka (International Energy Agency 1997). tion of asthma, changes in lung function, and Emissions from two-stroke engine vehicles are premature death (Holgate and others 1999, relatively low because of their low fuel consump- chapter 13). tion. Two-stroke engine vehicles account for about The health impact of particulate matter 11 percent of vehicular carbon dioxide emissions increases as the size of the particle diminishes. (8 percent by two-wheelers and 3 percent by Very fine particles-such as those emitted by the three-wheelers) and a very small share of methane combustion of transportation fuels-are believed and nitrous oxide emissions. to be particularly harmful. In addition, the fact Only 1-2 percent of total greenhouse gases in that they are emitted near ground level, close to South Asia can thus be tied to two-stroke engine where people live and work, suggests that vehicu- vehicles. This very minor contribution of two- lar emissions are even more harmful than their stroke engine vehicles to greenhouse gas share in total emission loads might indicate. (A emissions suggests that efforts to reduce such detailed discussion of the health impacts of emissions should target other types of vehicles, various pollutants is given in annex A.) such as heavy-duty buses and trucks, and sectors The health impact of oil droplet-based par- other than transport. Nevertheless, mitigation ticles is not well understood. Most health impact measures that reduce local pollution from two- studies have been carried out in countries that do stroke engines may lead to reduced greenhouse not have large two-stroke engine vehicles, where gas emissions as well (see chapter 2). Examples of the principal sources of fine particulate emissions such measures include switching to more fuel- are diesel vehicles and stationary sources. In all of efficient four-stroke engines and switching to these studies, sickness and death are regressed electric vehicles, especially where the electricity against the overall ambient particulate concentra- used to charge the vehicles is generated using a tions measured in terms of total suspended clean fuel such as natural gas.8 CHAPTER 2 Reducing Emissions from Two-Stroke Engine Vehicles >1 >. ith the exception of India, countries in opacity is limited to 15 percent for new vehicles South Asia have not yet adopted and 30 percent for in-use vehicles. measures used in other parts of Asia In India vehicle manufacturers faced the to mitigate emissions from two-stroke engines. challenge of meeting more stringent emission These include use of low-smoke lubricants, standards in 1996 without using catalytic convert- installation of oxidation catalysts, and mechanical ers, which could not be used because unleaded metering of lubricant. This section examines ways gasoline was not widely available (table 5). to improve the functioning of two-stroke engines. Manufacturers had to rely solely on improve- Chapter 3 looks at alternatives to two-stroke ments in engine technology to meet the mandated gasoline engines. emission limits. Today as a result of continuing technological advances, including the installation Declines in Emissions of catalytic converters, new two- and three- Emissions from recent two-stroke models have wheelers manufactured in India emit less than 16 decreased markedly as a result of technological percent of the carbon monoxide and less than 25 improvements. In Taiwan (China)-which has the percent of the hydrocarbons and nitrogen oxides largest number of two-wheelers per capita in the emitted by vehicles manufactured in 1991. world-emission standards have tightened Emission factors of new and well-maintained significantly (table 4). The emission standards in two-wheelers using the correct amount of lubri- Taiwan (China) also control visible smoke; smoke cant have declined in recent years. A scooter Table 4 Emission standards for gasoline-powered two-wheelers in Taiwan (China), 1988-2003 Catalyst durability Hydrocarbons and requirement Carbon monoxide nitrogen oxides Year Driving cycle (kilometers) (grams per kilometer) (grams per kilometer) 1988 ECE 40a warm None 8.8 5.5 1991 ECE 40 warm 6,000 4.5 3.0 1998 ECE 40 warm 15,000 3.5 2.0 2003 ECE 40 cold 15,000 7.0 i.0/2.0' Note: Emissions of carbon monoxide and hydrocarbons are higher when the engine is cold, so that the increase in the carbon monoxide limit between 1998 and 2003 does not represent a relaxation in emission standards but in fact represents some tightening. a. Economic Commission for Europe Regulation 40 for two- and three-wheelers. b. 1.0 gram per kilometer for two- stroke engines and 2.0 grams per kilometer for four-stroke engines. Source: Society of Indian Automobile Manufacturers. 13 14 Improvzng LfrbnAir Qualityin South Asia byReducngEmissions from Two-StrokeEngine Vehicles Table 5 Emission standards for gasoline-powered two- and three-wheelers in India, 1991-2000 (grams per kilometer) Two-wheelers Three-wheelers Carbon Hydrocarbons and Carbon Hydrocarbons and Year monoxide nitrogen oxides monoxide nitrogen oxides 1991 12_15a 8_9a b 30 l 2b 1996 4.5 3.6 6.75 5.4 1998 4.5 3.6 6.75 5.4 2000 2.0 2.0 4.0 2.0 Note: Tests of 1991 and 1996 vehicles were based on the warm Indian driving cycle. Tests of 1998 and 2000 were based on the cold Indian driving cycle. a. Emission standard depends on the reference mass of the vehicle. b. Limit applied to hydrocarbons only and not to the sum of hydrocarbons and nitrogen oxides. Source: Society of Indian Automobile Manufacturers. equipped with a catalyst, for example, emitted Measurement of particulate matter emissions just 0.015 grams of particulate matter per kilome- from two-stroke engines is difficult because oil ter in a recent test (table 6), but even this emission droplets from lubricant added to gasoline on a factor is many times greater than that of a compa- pass-through basis account for a large fraction of rable four-stroke scooter. particulate matter in the exhaust gas. Depending But data on emission factors for particulate on the dilution rate and the temperature to which the line downstream of the exhaust pipe (includ- matter must be interpreted with caution. Noll ing the dilution tunnel) is heated, these droplets estabishe metodolgy i accptedindutry- can condense before being collected on filter wide for measuring particulate emissions from paper. Oil samples condensed on filter papers can two-stroke engines. Nearly all the work carried also be lost as a result of the passage of gas out on two-stroke engine vehicles has focused on through the filter. reducing hydrocarbons (or the sum of hydrocar- A reliable and reproducible methodology for bons and nitrogen oxides), carbon monoxide, and measuring particulate matter emissions from two- visible smoke. No in-depth study has been stroke engines should be developed and conducted on particulate emissions. statistically significant data collected to enhance Table 6 Particulate matter emission factors for two-wheelers in India Particulate matter Odometer Amount of emissions Vehicle type (kilometers) lubricant Lubricant type (grams per kilometer) Motorcycle' 21 5 Metering API TC/JASO FC* 0.055 Scootera 550 2% JASO FB 0.032 Scooter with catalysta 550 2% JASO FB 0.015 Scooter, four-stroke' 650 n.a. n.a. 0.0005 Motorcycleb 19,000 Metering 0.025 Motorcycleb 3,000 3% 0.012 n.a. Not applicable. - Not available. Note: All vehicles are two-stroke engine vehicles without catalysts unless otherwise indicated. All vehicles are well maintained. The Indian driving cycle is used. *American Petroleum Institute TC and Japanese Standards Organization FC (see the section "Improving Lubricant Use" in this chapter). Source: a. Unpublished data from the Automotive Research Association of India and Bajaj Auto; b. Palke and Tyo 1999. RedudngEmi7ssionsfrom Two-SttvkeEngine Vehicles 15 understanding of emissions from these vehicles list. API canceled the system in 1993, deferring to and help policymakers select optimal measures the International Organization for Standardization for curbing emissions. (Annex B presents the (ISO) global specification and the Japanese results of recent tests of alternative hypotheses Standards Organization (JASO) system. Oil about measurement problems.) marketers continue to use the outdated test criteria established for API TC to certify air-cooled Improving Gasoline Quality oils. The API TC classification is currently the The adulteration of gasoline with kerosene is lowest acceptable level of 2T oil quality. likely to increase hydrocarbon and particulate In 1990 JASO created a two-stroke lubricant emissions. Because some of the gasoline effec- standard with three levels of quality (FA, FB, and tively bypasses the combustion chamber and is FC). Lubricity and detergency quality increase emitted uncombusted by the two-stroke engine, from FA to FC, and exhaust blocking and smoke eliminating or reducing such toxic components as emission improve. Maximum permissible levels organic lead and benzene from gasoline-a of smoke density are 50 percent for FA oil, 44 worthwhile step under any circumstances-is percent for FB oil, and 24 percent for FC oil. particularly important to mitigate the health Japanese manufacturers of two-stroke vehicles impact of toxic emissions from two-stroke en- identify FC (low-smoke lubricants) as their gines. minimum requirement. North America's API TC The high gum content and low octane level of oil rating is equivalent to JASO FB. gasoline also increase emissions. If gasoline is Since April 1999 the Government of India has unstable the gum content may become unaccept- required all two-stroke engine oils sold in the ably high, leading to the deterioration of country to meet both API TC and JASO FC carburetor settings and increased deposits, which specifications (that is, only low-smoke lubricating alter the air-to-fuel ratio. This in turn could cause oils can be used in India). In the National Capital the engine to misfire, damaging the vehicle and Territory of Delhi, 2T oil can be sold only in sealed significantly increasing emissions of hydrocarbons packages or premixed with gasoline and dis- and particulate matter comprising oil droplets. pensed through the pump nozzle. This ban on While the minimum research octane number unsealed packages is intended to discourage the (RON)9 requirement for two- and three-wheelers sale of recycled and other unsuitable engine oils. in South Asia is 87, Bangladesh still markets 80 The sale of premixed gasoline is intended to octane gasoline widely. Depending on how the encourage the use of not only the suitable quality driver accelerates, 80 RON gasoline can cause but also the correct amount of 2T oil. knocking and engine malfunction-and hence higher emissions. Using the correct concentration of lubricant The use of the correct amount of 2T oil signifi- cantly reduces two-stroke vehicular emissions. Many drivers of two-stroke engine vehicles use New lubricant formulations even allow certain excessive quantities of the wrong kind of lubricant makes of two-wheelers to cut the lubricant (see chapter 1). Correct use of lubricant can go far requirement to just 1 percent. Table 7 shows to reduce emissions from these vehicles. indicative emission factors as a function of the amount of lubricant and type for well-maintained motorcycles without any advanced emission In the mid-1980s the American Petroleum Insti- control technologies. Particulate matter emission tute (API) and the Coordinating European factors in the table are approximations based on Council for the Development of Performance limited available data and indicative of general Tests for Transportation Fuels, Lubricants, and trends only. Since particulate emissions are not Other Fluids set up a provisional two-stroke regulated in Asia, relatively little data are lubricant performance and service classification available. 16 Improving Urban AirQualityin South Asia by ReducingEmissions from Two-StrokeEngine Vehides Table 7 Relation between lubricant content and emissions by uncontrolled motorcycles Particulate matter emissions Hydrocarbon emissions Grams per Percent Grams per Percent Lubricant content kilometer reduction kilometer reduction 6-8%, regular 2T 0.6-0.7 n.a. 8.5 n.a. 5% maximum, regular 2T 0.35 50 7.0 18 2-3%, regular 2T 0.25 64 6.5 24 1-2%, regular 2T 0.20 71 6.0 29 1% maximum, low-smoke 0.15 79 5.7 33 n.a. Not applicable. Note: Based on an average speed of 20 kilometers per hour. Source: Mario Camarsa, Enstrat International Limited, personal communication (1999). Using lo w-sm oke lubricant smoke lubricant may reduce visible smoke, it may The use of low-smoke lubricant significantly not reduce mass particulate emissions (Radian reduces emissions of visible smoke. The retail International 1998 and unpublished data from prices of lubricants in India in March 2000 are ARAI). Thus the public health benefit of using given in table 8. If drivers using 6 percent JASO low-smoke lubricant is not clear. FB oil cut back the amount of lubricant to 3 percent and simultaneously switch to JASO FC MeteringJubricant (low-smoke lubricant), they can realize savings of A mechanical lubrication system, which adjusts about 35 percent in lubricant costs. the amount of lubricant metered into gasoline to In Bangkok, several motorcycles with varying the engine speed and load, can control the amount levels of visible smoke emissions were selected to of lubricant added to gasoline. Such a system see if visible smoke was correlated with mass reduces emissions by making it impossible for particulate emissions. Some of the test results are drivers to add excess lubricant to gasoline. shown in table 9. The mass particulate emissions However, mechanical lubrication may not yield for all the three driving cycles showed weak any greater benefits than drivers adding the correlations with opacity for two-stroke engine correct amount of lubricant. vehicles using regular 2T oil. One four-stroke engine vehicle is included in the table to illustrate Improving Vehicle Design its low opacity as well as mass particulate emis- In response to national standards more stringent sions. Limited data on the impact of switching than those of the European Union (see box 2), from regular 2T oil to low-smoke lubricant on Indian vehicle manufacturers have made engine particulate emissions indicate that while low- design changes that have reduced the level of Table 8 Retail prices of lubricants in India, March 2000 (Indian rupees) Price of Price of 3 percent Price of 6 percent lubricant oil per liter of oil per liter of Lubricant per liter gasoline gasoline Two-stroke oil meeting JASO FB 80-90 2.4-2.7 4.8-5.4 standard Two -stroke oil meeting API TC and 100-120 3.0-3.6 6.0-7.2 JASO FC standards Crankcase oil meeting API standard 80-90 2.4-2.7 4.8-5.4 SCa Note: a. API SC is a grade of crankcase oil for four-stroke engine gasoline vehicles. ReducingEm7issions frm Two-StrokeEngine Vehides 17 Table 9 Particulate matter emission factors for motorcycles in Bangkok (grams per kilometer, except where otherwise indicated) Opacity Driving cycle Typee (percent) ECE 40 FTP 75 Bangkok Four-stroke 7 0.01 0.12 0.02 Two-stroke 20 0.26 0.26 0.04 Two-stroke 54 0.29 0.22 0.22 Two-stroke 77 0.19 0.18 0.13 Two -stroke 86 0.47 0.70 0.29 Two-stroke 100 0.41 0.23 0.14 Note: ECE 40: Economic Commission for Europe test cycle 40. FTP 75: U.S. Federal Test Procedure 75; Bangkok: Bangkok driving cycle developed by Radian International. Percent opacity was measured under free acceleration. All the motorcycles tested had built-in automatic lubrication systems and used regular 2T oil. Source: Radian International 1998. emissions and increased fuel economy. Scaveng- carbon monoxide and hydrocarbon emissions but ing losses have been reduced steadily, and in 2000 not nitrogen oxides, rather than three-way cata- catalytic converters were installed for the first lysts commonly installed in passenger cars, which time. also reduce nitrogen oxide emissions. Catalytic converters for two-stroke engines are not de- Installing catalytic con verters signed to achieve as high a level of conversion of Catalytic converters for two- and three-wheelers carbon monoxide and hydrocarbons as those for are oxidation catalysts, which reduce the level of four-stroke engine passenger cars because of the Box 2 Emission standards from around the world The emission standards for two-wheelers differ markedly. The emission standards in India and Taiwan (China) today rank among the most stringent in the world, reflecting the concern of the authorities with controlling emissions from vehicles that are numerous and popular because of their affordability and ease of maneuver. The emission standards shown below came into force in 2000, with the exception of those for Taiwan (China), which came into effect in 1998. 14 ____ i-Japan EU 4 stroke E o 12 4 stroke 10 0. 8 6~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ o 4 - - EU 2 stroke 2 Taiwan (China) c -- India 0 0 I 2 3 4 5 Hydrocarbon emissions and nitrogen oxides (grams per kilometer) 18 Improving bThan Air QualitvinSouthAsia byReducingEmissions5from Two-Stroke Engine Vehicles greater quantity of hydrocarbons and lubricant in proper maintenance is critical to reaping the full the exhaust gas. They typically reduce exhaust benefits of investments in emission mitigation. emissions by half. Simple servicing procedures, such as cleaning and Catalysts deactivate more rapidly in two- adjusting the carburetor, adjusting the ignition stroke engine vehicles, partlv because of higher 9 ~ ~~~ I system, cleaning and adjusting or replacing spark exhaust gas temperature, and need to be replaced plugs, and cleaning air filters, can reduce exhaust frequently. India is considering minimum catalyst emission levels significantly (ARAI 1998). Air durability requirements. Taiwan (China) has had filters should be cleaned or replaced every 3,000 catalyst durability requirements for motorcycles k for some time, initially set at 6,000 kilometers and kilometers. bor tunedtand at 15,000 kilometers today. For three-wheelers in cleaned every 3,000 kilometers for two-stroke South Asia, which are often driven 120 kilometers engines and every 5,000 kilometers for four-stroke a day, 15,000 kilometers is equivalent to less than engines. six months of operation. For a vehicle driven 10 Because lubricant passes through the two- years or more, as many two-stroke vehicles in stroke engine on a once-through basis, there is South Asia are, the catalyst might have to be considerably more deposition and accumulation replaced up to 20 times to maintain the original of carbonaceous deposits in the combustion level of particulate emissions. This is clearly a chamber, exhaust port, and silencer than in four- problem. stroke engine vehicles. As a result more frequent In India the Society of Indian Automobile decarbonization is needed. Bajaj Auto recoi- Manufacturers (SIAM) is offering the government mends decarbonization every 6,000 kilometers for a warranty of 30,000 kilometers for all two- and t three-wheelers equipped with catalytic convert- three-wheelers and 9,000 kilometers for scooters. ers. Catalyst durability of 30,000 kilometers Four-stroke engines do not normally need decar- would enable drivers to replace their catalysts at bonization. Bajaj also recommends replacing the same intervals as they have their engines spark plugs every 7,500 kilometers for two-stroke overhauled. engines and every 10,000 kilometers for four- To meet year 2000 emission standards, the stroke engines. Decarbonization requires mainly three-wheelers manufactured in India are labor, which is relatively cheap in South Asia, equipped with catalytic converters for both two- keeping maintenance costs low. stroke and four-stroke engine designs. The It is not clear whether long-run maintenance net-of-tax cost of the catalytic converter fitted in costs are higher for two-stroke or four-stroke three-wheelers for both engines is approximately engines. Four-stroke engines have many more 1,100 Indian rupees, or US$25. moving parts (valves, camshafts, timing chains, Reducingscavenginglosses oil pumps), which are relatively expensive because they tend to be sold by vehicle manufac- A majr are of esearh anddeveopmen has turers. In contrast, parts for two-stroke engines been the attempt to reduce scavenging losses to are sold by a large number of parts suppliers. increase fuel economy and reduce emissions (box aesl yalrenme fprssples inres fuestantl reducnomy hand reduen ehisn (box Labor costs for servicing four-stroke engines are 3). Substantial reductions have been achieved by designing better port configurations. In India, for also higher because of the higher level of skills example, short-circuiting fuel losses have been required. Engine overhauls for two-stroke engines reduced from 35 percent in 1991 to as low as 14 are more expensive, however. Minor engine percent in the year 2000 model as a result of overhauls, not normally required on four-stroke design changes (Iyer 1999). engines, are typically required every 30,000 kilometers for two-stoke engines. Major over- Improving Maintenance hauls, which may also be needed on four-stroke The importance of an effective inspection and engines, are required every 90,000 kilometers for maintenance program cannot be overemphasized: two-stroke engine three-wheelers. 19 Box 3 Reducing scavenging losses in two-stroke engines Several technologies are being tested to reduce emissions from two-stroke engines (see table below). The goal is to retain the advantages of the tvo-stroke engine while gaining control over the air-to-fuel ratio and eliminating the loss of air-fuel mixture through the exhaust port. Injecting fuel into the engine instead of introducing it through the carburetor may dramatically reduce or eliminate scavenging losses. Direct injection of the fuel into the engine also makes it possible to use leaner air- fuel mixtures through charge stratification. The effectiveness of a variety of systems that could be suitable for small engines has been demonstrated in laboratories, although none has yet been developed commercially. The technologies being tested include: * Spraying pressurized fuel into the intake port or crankcase with controlled injection timing. * Injecting a fuel spray into the transfer port or the piston. * Injecting fuel into the cylinder as or after the exhaust port closes. * Directing the in-cylinder injection toward the cylinder wall to improve fuel atomization, vaporization, and mixing. * Using "skip firing" along with fuel injection to shut off fuel injection in some cycles to allow sufficient time for the exhaust gases to be purged from the combustion chamber. All of these measures would require an electronic engine management system for precise control of the fuel injection timing and quantity, depending on the engine load and speed. They would thus add to the cost of the vehicle. Emissions generated by various engine technologies (grams per kilometer) Oxides of Technology Hydrocarbons Carbon monoxide nitrogen Carburetor system 3.8 3.7 0.03 Cylinder wall injector 2.9 3.4 0.06 Semidirect injection 0.8 0.8 0.1 Electromechanical direct injection 0.8 0.8 0.1 Loop-scavenged two-stroke engine with air- 0.5 0.4 0.05 assisted direct injection Air-assisted cylinder head injector with skip 0.28 0.09 0.16 injection and catalytic converter Source: Huang and others 1993; Kirchberger 2000. CHAPTER 3 ;fsw._ Alternatives to Two-Stroke Gasoline Engines rjehicle and fuel alternatives to two-stroke resulting in 10-20 percent greater fuel efficiency \ gasoline engines can reduce exhaust (table 10). Savings from better fuel economy V emissions. Cleaner alternatives include would easily offset the higher purchase price of four-stroke engines and engines powered by four-stroke engine vehicles, making this a poten- liquefied petroleum gas, compressed natural gas, tially strongly cost-effective way to reduce and electricity. pollution. Four-stroke engine two-wheelers have been on Four-Stroke Gasoline Engines the market for some time. All motorcycles sold in If gasoline is retained as the fuel of choice, replac- the United States are of four-stroke design. ing two-stroke vehicles with four-stroke vehicles Mishuk in Bangladesh has been selling four-stroke would significantly reduce hydrocarbon and engine three-wheelers for a number of years. particulate emissions. Emissions of nitrogen oxide Four-stroke engine three-wheelers were not would increase, however. available in India until mid-2000, when Bajaj Auto Because there are no scavenging losses in four- began marketing them there. Year 2000 model stroke engines, a much larger percentage of the three-wheelers are equipped with catalytic fuel is combusted in the combustion chamber, converters for both two-stroke and four-stroke Table I 0 Fuel economy of two-stroke and four-stroke engine vehicles On-road fuel Engine size Laboratory test economy (cubic fuel economy (kilometers Vehicle type Engine type Model year centimeters) (kilometers per liter) per liter) Scooter Two -stroke Post- 1996 150 55 52 Scooter Four-stroke Post- 1996 150 62 59 Three- Two -stroke Pre- 1996 150 24 20 wheeler Three- Two -stroke Post- 1996 150 28 25-27 wheeler Three- Four-stroke 2000 175 33 30-31 wheeler Source: ARAI test of Bajaj vehicles using the Indian driving cycle; Bajaj laboratory tests; ARAI and Bajaj estimates for on-road fuel economy. 21 22 Improving LrbanAirQualiiiin South Asia byReducingEmissions from Two-StrokeEngine Vehides engines. The ex-Delhi showroom prices are Shakti Gas have jointly developed a conversion Rs.66,579 for two-stroke and Rs.70,463 for four- kit to run three-wheelers on LPG. stroke engine three-wheelers, with a price While not as good as CNG, LPG has superior difference of Rs.3,884 (US$88). This incremental antiknock characteristics compared to gasoline. cost is easily recovered in fuel savings in less than Propane has an antiknock index (the average of a year by operators of four-stroke engine research and motor octane numbers10) of 104, autorickshaws (see chapter 4). allowing LPG-powered engines to operate at Diesel three-wheelers have even higher fuel slightly higher compression ratios than gasoline- efficiency than four-stroke engine vehicles. powered vehicles. In India vehicle manufacturers Moreover, because they are based on a four-stroke have proposed a minimal motor octane number engine design, lubricant does not need to be for automotive LPG of 89 to ensure that about 90 added to the fuel. Diesel three-wheelers are also percent of LPG is propane. manufactured to meet particulate matter emission The main problems in introducing LPG into standards. However, diesel exhaust has recently the transport sector in South Asia are the lack of been found to be more toxic than previously sufficient domestic sources of supply and the believed. And diesel three-wheelers are consider- inadequate distribution system. India, Pakistan, ably noisier than gasoline three-wheelers. Diesel and Sri Lanka import about 30-40 percent of LPG engines are thus probably not a good alternative consumption. There is also a need to invest in to gasoline-powered two-stroke engines, refueling equipment required to transfer pressur- ized LPG from storage tanks to vehicles and to Vehicles Powered by Liquefied ensure that no LPG escapes during refueling. The Petroleum Gas lack of adequate investment in LPG refueling stations constrains widespread use of LPG in Liquefied petroleum gas (LPG) is a mixture of South Asia. light hydrocarbons, mainly propane/ propene and butane/butenes. It is easier to distribute and Vehicles Powered by Compressed store than compressed natural gas, liquefied at Natural Gas pressures of 4-15 bar. Switching to CNG reduces particulate matter and LPG is a much cleaner automotive fuel than hydrocarbon emissions significantly. The combus- gasoline. If LPG (or CNG) vehicles are based on a tionocn alsolds ssently no volatil two-stroke engine design, lubricant will still need organic compounds or sulfur oxide emissions. to be metered and injected into the combustion Moreover, because natural gas is lighter than air chamber, thereby partially offsetting the emission on escape it will not lie on the ground or enter reductions achieved as a result of replacing sewage systems. CNG is expensive to distribute gasoline with a gaseous fuel. Since lubricant .an sste,showever, requiringcompressionuto cannot be premixed with LPG, it is metered into about 200 bar. the vehicle engine, eliminating the possibility of Both Bangladesh and Pakistan are piloting the overlubrication. LPG also contains fewer highly use of CNG vehicles. In Bangladesh a pilot reactive hydrocarbons and has a lower sulfur program funded by the Canadian International content than gasoline or diesel fuel. LPG does Development Agency converted four three- contains light olefins, highly reactive hydrocar- wheelers in mid-2000; a larger demonstration bons that increase emissions and lower the involving 20-50 vehicles will follow. In Pakistan a knock-limited compression ratio, diminishing donor-funded program plans to test 10-30 ve- engine performance. hicles in Karachi, Lahore, and Quetta. In both LPG three-wheelers are used widely in Thai- programs one tank of CNG is estimated to have a land. Fueling vehicles with LPG is illegal in India, range of about 100 kilometers. Bajaj Auto in India although this situation is likely to change in the has developed CNG-powered three-wheelers near future. Three-wheelers have been illegally based on a four-stroke engine design, which it converted to LPG use in Bangalore. ARAI and launched in mid-2000. Altematves to Two-Stroke GasolineEngines 23 Vehicles can be produced to run on either CNG able. But governments have a disincentive to or gasoline. Such vehicles make less efficient use reduce the price of CNG since this would reduce of CNG, however, losing about 10-15 percent of their tax revenues as consumers shift from (taxed) their power output. Efficiency is also lost as a fuels to (essentially untaxed) CNG. result of the extra weight of carrying two fuel In countries such as India that will soon start systems. importing liquefied natural gas on a large scale (a Methane, which constitutes the bulk of CNG, source of natural gas in the future), it would be has an antiknock index of more than 120. Vehicles difficult to keep CNG prices much lower than that run on CNG can thus take advantage of the gasoline prices if world crude oil prices were to high octane number of the fuel and operate at a fall markedly. In contrast, Bangladesh, which has high compression ratio. In practice the composi- large natural gas reserves and extensive networks tion of pipeline natural gas varies, depending on of gas pipelines in large cities, might be able to the source and processing of the gas as well as the introduce CNG into the transport sector without time of the year. As a result, not only does the fuel compromising other needs in the economy. octane number vary but the heating value can However, natural gas is effectively subsidized in vary by as much as 25 percent, affecting vehicle Bangladesh. In 1998 the price of natural gas was performance. Moreover, when used as fuel in estimated to average about 25 percent less than its vehicles, the heavier hydrocarbons in natural gas economic opportunity cost. Once the gas sector is can condense and revaporize, affecting the level restructured to reflect market prices, the econom- of fuel enrichment. Changes in fuel enrichment ics of CNG vehicles will become less favorable affect both emissions and engine performance. than they are today-something that must be The water content of natural gas is also a concern considered in assessing a CNG vehicle program. because of its tendency to form solid hydrates and corrode transmission pipes, vehicle storage tanks, Electric Vehicles and refueling stations. Electric three-wheelers cost much more than The long-term viability of CNG vehicles gasoline-powered vehicles, have shorter ranges, depends on a favorable legislative and regulatory and run on batteries that take up to 6-10 hours to atmosphere and fuel prices that are not distorted recharge. Until technological changes make these by subsidies. Efforts to encourage the purchase of vehicles more attractive, they are not expected to CNG vehicles through subsidization are unsus- play an important role in South Asia. tainable-as New Zealand's failed attempt to Electric vehicles currently operate on lead acid jumpstart the conversion to CNG illustrates. New batteries.11 When the batteries are charged Zealand's aggressive program of financial incen- indoors, good ventilation is necessary, because tives, including subsidies, led to the conversion of hydrogen is emitted as lead acid batteries re- 110,000 vehicles to natural gas between the early charge. Preliminary estimates in India price the 1980s and 1986. When the government withdrew batteries at about $40-$50 apiece for three- its support, however, the market for CNG vehicles wheelers that operate on eight batteries. The eight essentially died: today only about 10,000 such batteries and required vehicle modifications are vehicles remain on the road. As the International expected to increase the cost of electric three- Association for Natural Gas Vehicles put it, wheelers by about $1,000, effectively doubling the "Governments that believe that all they need is a price of the vehicles relative to gasoline-fueled two- to three-year kick-start are wasting their time three-wheelers in India. and money" (Cumming 1997). The economic viability of electric vehicles For converting to natural gas to make eco- depends in part on the price of electricity. The nomic sense, the retail price of CNG needs to fall power sector in South Asia is being reformed and to about 55-65 percent of the cost of the fuel being restructured. The long-term viability of electric replaced. Without consistently lower prices, vehicles should be evaluated based on market promotion of CNG vehicles will not be sustain- pricing of electricity. 24 Improving UrbanAir QualityinSouthAsia byReducingEnmissions from Two-StrokeEngine Vehides Given the current state of technology, electric percent. In early 2000 about 500 electric Tempos vehicles are not expected to have widespread operated in Kathmandu, partly in response to the applications in South Asia. They could play a ban on diesel Tempos imposed by the government useful but limited role, however, in extremely in 1999. Seven plants assembled more than 200 polluted traffic corridors. In Kathmandu, Nepal, electric Tempos in 1999. This is the world's largest for example, electric Tempos were introduced in fleet of electric road public passenger transport 1994 (box 4). In 1995 the government reduced vehicles. The future is not secure, however, as the import duties on electric vehicle components from government approved in May 2000 the import of 60 to 5 percent, and duties on fully assembled 300 15-seat vans with the same preferential import electric vehicles from as much as 150 percent to 10 duties accorded to the electric vehicles. Box 4 Converting diesel three-wheelers to electric Tempos in Kathmandu An important mode of public transport in Kathmandu is the Tempo, a 10-passenger three-wheeler that operates as a minibus. Before the government banned diesel Tempos in Kathmandu in 1999, about 1,500 of the vehicles operated in the city. A pilot program to convert diesel Tempos to electricity was conducted in 1994-96 by Global Resources Insti- tute with the support of the U.S. Agency for International Development (Moulton and Cohen 1997). The electric Tempos in the pilot program, called Safa (clean) Tempos, had an operating range of 50 kilometers and a maximum speed of 45 kilometers an hour. Their batteries weighed 360 kilograms, so that when full the vehicle operated close to its maximum design load. The brakes also operated close to design limits. To allow the vehicles to travel 150 kilometers a day, three sets of batteries were used. Specified stops loading and unloading passengers-a new concept in Nepal-were established so that the vehicles could operate on a schedule. The Safa Tempos are cleaner and quieter than diesel Tempos, and public acceptance of the vehicles has been high. In fact, demand from passengers often exceeded available space during the pilot period. CHAPTER 4 Policy Options P olicymakers can deal with pollution by industries to seek the lowest-cost means of setting emission targets that vehicles complying with the standards. Vehicle manufac- must meet or by mandating specific types turers prefer emission-based policies, which allow of fuel or vehicle technology in the hope of them to explore different technology options and achieving emission targets. Emission-based select technologies themselves on the basis of measures provide greater flexibility to suppliers market requirements and their research and of fuels and vehicles, who can choose the lowest- development activities. Emission-based policies cost options for meeting the specified emission work well if the automobile and oil industries targets. Provided that compliance can be ensured, cooperate. Without cooperation, each industry has this approach is generally a lower-cost option for an incentive to unload capital-intensive activities society. However, emission-based measures are onto the other. usually more difficult to monitor than technology- Stricter emission standards are apparently based options. Technology based options are not pushing Indian manufacturers to build more four- likely to be a low-cost solution unless rigorous stroke engine vehicles. Moving to a four-stroke cost-benefit analysis is performed to identify the engine appears to be cost-effective: an optimal techn e f. 'autorickshaw driven 120 kilometers a day 300 optmal technologises for each specific situation. days a year would save about Rs.7,200 a year (For a brief discussion of available software for (based on the prices of 87 octane gasoline and evaluating emissions , anex C.) lubricant for two-stoke engine vehicles meeting The distinction between emission-based and JASO FC standards in mid-2000). Since the ex- technology-based policies is not necessarily sharp, Delhi showroom price difference between a because vehicular emission standards can be two-stroke and a four-stroke engine vehicle is made so stringent that they effectively dictate the Rs.3,900, the incremental cost of purchasing a type of vehicle or fuel that must be used. An four-stroke engine three-wheeler is recovered in a example is the year 2003 emission standards in little over half a year. Assuming that maintenance Taiwan (China), which set tighter emission costs are comparable, replacing old autorickshaws standards for two-stroke engines than for four- with new four-stroke engine autorickshaws is stroke engines, effectively banning two-stroke therefore a cost-effective way of reducing fine two-wheelers. particulate emissions. Emission-Based Policies Monitoring emissions Emission-based policies set vehicular emission While checking compliance of new vehicles may standards and allow the automobile and oil not be difficult, monitoring the performance of in- 25 26 Improving Urban AirQualityin South Asia byReduingEmissions from Two-StrokeEngine Vehides use vehicles is a far greater challenge. At a mini- the importance of finding ways to enforce emis- mum, an effective inspection and maintenance sion standards and deal with noncompliance, program needs to be in place, together with an given that neither the owners nor the drivers have up-to-date vehicle registry. Even when imple- an incentive to spend time having commercially mented rigorously, however, inspection and operated vehicles inspected. maintenance have limited effectiveness because owners and mechanics can temporarily adjust Technology-Specific Policies vehicles, particularly older technology vehicles, so Measures based on fuel and vehicle technology that they pass emissions tests. mandate the minimum technology to be adopted. One way to ensure that emissions consistently Technology-specific policies include: meet standards is to spot-check vehicles on the * Mandating higher-quality two-stroke engine road. However, such tests are expensive to set up lubricants and administer and invite corruption. * Mandating premixing of gasoline and lubricant To increase the effectiveness of inspection and maintenance programs, the frequency of inspec- * Mandating installation of catalytic converters tion could vary with the age of the vehicle as well * Banning two-stroke engines as the annual number of kilometers traveled. * Banning or providing incentives to scrap Commercial vehicles such as three-wheelers could vehicles that have reached a certain age or be inspected more frequently than motorcycles number of kilometers traveled driven for private use. Frequent inspection is particularly important * Mandating or providing incentives (tax credits, once oxidation catalysts are installed. If catalysts tax reduction, tax elimination, or subsidies) for last about 30,000 kilometers and taxis are typically replacing two-stroke gasoline engine vehicles driven in two shifts for 150 kilometers a day, with four-stroke engine vehicles inspection and replacement of catalysts would be * Mandating or providing incentives for necessary twice a year. replacing two-stroke gasoline engines with alternative fuels such as liquefied petroleum Repairing vehicles thatfailinspection gas, compressed natural gas, and electricity. Vehicle inspection will be ineffective if vehicles Where emission-based policies are difficult to that fail are not repaired promptly. The availabil- monitor, it may make sense to adopt some of ity of adequately equipped and trained mechanics these policies. Before this is done, however, it is is a prerequisite for a successful inspection and imperative that policymakers examine the cost- maintenance program. Since four-stroke engine effectiveness of each option. Some measures make vehicles are more complex and require higher more sense to mandate than others. Banning the mechanical sophistication to service, training of sale of unpackaged lubricant would prevent mechanics should be given high priority in the inferior quality lubricant from being added to coming years. There is currently a shortage of gasoline (box 5). Requiring that all new three- mechanics who can service four-stroke engine wheelers use four-stroke technology may be three-wheelers and vehicles with increasingly reasonable given the fuel cost savings, provided sophisticated technology in general, and of repair that enough mechanics are trained to service four- shops with diagnostic tools to service such stroke engine three-wheelers. vehicles. In contrast, the rationale for mandating Where vehicles are not driven by their owners, catalytic converters is much weaker, since they the incentives for regular inspection and mainte- can function efficiently only if several conditions nance, weak in the best of circumstances, are even are satisfied: weaker, since the vehicle owner who is respon- * Unleaded gasoline must be widely available. sible for passing inspection does not have the Ideally, leaded gasoline would be completely vehicle most of the time. This dilemma highlights phased out to eliminate the chances of fueling PoicyOptions 27 catalyst-equipped vehicles with leaded mends that only two-stroke engine vehicles built gasoline. after 1996 be considered for retrofitting. * Gasoline must have a reasonably low level of Reducing particulate matter by mandating sulfur, preferably less than 500 parts per catalysts may not be cost-effective. It is difficult to million by weight. estimate the impact of oxidation catalysts on particulate matter emissions because data are * Emission levels and the length of time the scarce. Assuming catalyst conversion efficiency of catalyst system must meet those levels must be 50 percent, a particulate matter emission factor specified. without catalysts of 0.1-0.2 grams per kilometer, * An effective inspection and maintenance and catalyst durability of 30,000 kilometers, the system must be in place to ensure that catalytic total amount of PM10 eliminated by the catalyst converters are replaced as needed. would be 1.5-3.0 kilograms. This translates to If these conditions are not met, the benefits of US$8,000-17,000 per ton of PM1O given the net-of- catalytic converters may not justify the cost of tax catalytic converter cost of US$25 apiece in India. installing them. Even if these conditions are met, it This figure varies severalfold depending on the still makes sense to specify emission levels for assumptions made about the durability of the new vehicles rather than mandate catalytic catalyst and the amount of particulate matter converters. Retrofitting in-use vehicles with reduced, but the cost figures remain on the high side catalytic converters is problematic because compared with other PM,, reduction strategies. misfires, which are more common in two-stroke Banningaltwo-stroke engines engines, can cause temperature runaway and catalyst sintering and damage the catalyst as a Banning all two-stroke engines would eliminate result. For this reason Bajaj Auto in India recom- point-to-point transportation for millions of South Box 5 The role of the supreme court in air quality management in Delhi In July 1998 the Supreme Court of India mandated several measures affecting two- and three-wheelers in Delhi to combat air pollution: 1. Banning the sale of loose 2T oils at filling stations and service garages, effective December 1998. 2. Mandating that filling stations mechanically meter lubricant to be mixed with gasoline at the point of gasoline sale for two-stroke engine vehicles, effective December 1998. 3. Mandating the replacement of all pre-1990 autos and taxis with new vehicles using clean fuels, effective March 2000. 4. Introducing financial incentives for replacing all post-1990 automobiles and taxis with new vehicles using clean fuels, effective March 2001. The first three measures have been implemented. The third measure effectively requires that pre-1990 autorickshaws be retired from Delhi and replaced with autorickshaws powered by compressed natural gas. The only two "clean" fuel options, until the use of liquefied petroleum gas is legalized in India, are natural gas and electricity. No electric-powered autorickshaws are commercially available for sale in India today. The fourth measure has had an interesting history. The Delhi government offered financial incentives until March 2000 to replace autorickshaws 15 years old or older with new vehicles meeting the April 1996 emission standards. Although both two-stroke and four-stroke engines were permitted in principle, only two-stroke en- gine autorickshaws were available during this period. The incentive package consisted of complete exemption from sales tax (6 percent until 2000, when it was raised to 12 percent) and subsidized loans from the Delhi Finance Corporation. The loan repayment period, ranging from three to five years, could be negotiated. As of April 2000, the financial package is offered only for the replacement of old autorickshaws with new autorickshaws running on compressed natural gas or electricity. Autorickshaw owners' response to the measures has been overwhelming. By March 2000 nearly 20,000 old autorickshaws had been replaced by new ones. While the order allows owners to sell their old vehicles outside the National Capital Territory of Delhi, most owners chose to scrap their vehicles. Pollution is thus not trans- ferred to other parts of the country, and there is no possibility of these old vehicles migrating back to Delhi. 28 Imp-roving UrbanAirQaliftyinSouthAsiabyRedudngEmissionsfmom Two-StrokeEngine Vehicles Asians and cause hardship until there are enough sufficient credit exists for vehicle owners and buses and four-stroke engine taxis to replace the drivers to be able to finance the purchase of the large existing stock of two-stroke engine three- newer vehicles. wheelers. Women and families, who depend on the vehicles more than other groups, and the Fiscal and Trade Policy Options many people who use these vehicles commercially Whether or not the technology-specific measures would be particularly hard hit by a ban. Taking are adopted, economic policy options exist to two-stroke three-wheelers off the road precipi- encourage the removal of older and more pollut- tously would also affect the livelihoods of tens of ing vehicles from polluted cities. These options thousands of drivers and invite widespread include providing tax incentives for renewing agitation. Moreover, banning existing two-stroke vehicles, offering cash for older vehicles to get engines without putting in place a well-docu- them off the road, ensuring credit for purchasing mented vehicle registration system, an effective new vehicles, and liberalizing the trade in new traffic police force, and transport alternatives for vehicles. Not all options are equally recom- the current users could lead to increased harass- mended. ment of drivers and corruption by traffic police. Thus rather than banning these vehicles, Taxincentives for vehicle renewal policymakers should consider other lower-cost poptionsaors reduldcing sheir emissons. lower-cThe structure of taxes and other vehicle charges, such as annual registration fees, should be care- Moreselectivebans fully reviewed and revised if necessary where such structures do not capture the cost of pollu- Lower cost and politically more viable options to tion. For example, the import tariffs or sales taxes banning all two-stroke engine vehicles are to: on cleaner alternatives to autorickshaws (whether (a) Ban only older (and typically more polluting) new vehicles or parts for vehicle retrofitting) two-stroke engine vehicles from urban areas. should not be so high as to discourage their This approach has already been taken in Delhi, purchase-since the public health benefits to be with widespread popular support (box 5); gained are high. Similarly, annual registration fees and/or based solely on the market value of the vehicle, (b) Ban new two-stroke engine vehicles. This is rather than on market value and pollution emit- likely to have less socioeconomic impact than ted, would be too low to discourage the use of banning all such vehicles, since the cost older vehicles in urban areas. In assessing each of difference between new two- and four-stroke these measures, policymakers need to weigh the engines is not significant. If operating and socioeconomic cost of making it more expensive maintenance costs are taken into account, to own old vehicles against the health benefits of owning a four-stroke engine vehicle may be reducing vehicular emissions. more economical than owning a two-stroke engine vehicle. Removing financial Offering cashpayments for older vehicles toremove disincentives for replacing two-stroke engine them from the road three-wheelers with four-stroke engine vehicles Government purchase of older vehicles can distort is a high-priority. the market and have the perverse effect of keep- Either of these two options would be best ing older vehicles in use. If the government offers pursued if the following conditions are met: (i) to buy older vehicles, the price of those vehicles, alternatives to the vehicles being removed are many of which may be on the verge of being readily available and market-tested; (ii) these scrapped, will rise. A vehicle is typically scrapped alternatives are affordable, which may require the when the cost of repairing it exceeds the market lowering or elimination of import duties or other value of the vehicle after repair. The higher prices taxes on new vehicles (see below); and (iii) of older vehicles may have the unwanted effect of Policy Options 29 inducing some owners to keep and repair their stickers containing basic information on the old vehicles rather than scrapping them. More- quality and quantity of gasoline and lubricant. over, because vehicle prices are typically higher * In Dhaka, Bangladesh, the joint United Nations inside urban centers than outside, nonurban Development Programme-World Bank Energy owners of old vehicles would have an incentive to Sector Management Assistance Programme bring their vehicles to urban centers and sell them (ESMAP) carried out a series of training there. These problems indicate that cash payment sessions for mechanics and auto clinics for by the government for old vehicles is not the best three-wheeler taxi drivers in late 2000. The use of limited public resources. program was based on the idea that the first Ensu-ring a dequa te credi t step toward adoption of good practice is dissemination of accurate information by In lieu of offering cash payments, the more mechanics to taxi drivers. valuable role for government is helping to ensure * A major public awareness campaign in Delhi, the availability of credit through regular credit India, in late 1999 led to more than 66,000 and micro-credit markets to urban public trans- vehicles participating in free inspection and port vehicle owners and drivers. This would maintenance clinics for two-wheelers (Iyer facilitate their replacing older autorickshaws-as 2000) (box 6). well as larger vehicles, such as diesel and two- stroke engine gasoline Tempos-with cleaner Although public awareness initiatives have ones. been taken throughout the region, many drivers continue to maintain their vehicles inadequately. Liberalizingtradeinnew vehicdes Much more needs to be done to improve public understanding of the importance of proper Liberalizing trade in new vehicles could also help vehicle maintenance. reduce emissions. Making the technology avail- able in the rest of Asia readily available to Future Directions consumers in South Asia would allow them to meet tighter emission standards at lower cost. Two-stroke engines make up much of the total Rules such as local content requirements, based vehicle fleet because they are relatively inexpen- on the infant industry argument, often result in sive, perform well in terms of power and speed, inefficiency. High import tariffs, rigid licensing and are easy to repair. Precisely because two- schemes, and quotas on foreign-made vehicles are stroke engines are so numerous and popular, any all likely to slow the rate of vehicle renewal, policy decision to address emissions from these preventing a decline in emissions. vehicles must take socioeconomic consequences into account. A large-scale immediate ban on Public Education gasoline-powered two-stroke engine vehicles Emissions from two-stroke engines and repair would be extremely difficult and costly, but costs can be reduced by encouraging owners to fortunately numerous small and cost-effective carry out regular maintenance and use lubricant improvements are available. Public education and specifically manufactured for use in two-stroke awareness raising-about the health impact of engines at concentrations recommended by the emissions, the engine / fuel / lubricant parameters vehicle manufacturer. Mass public education will that increase emission levels, simple steps drivers be needed to induce vehicle owners to adopt these can take to reduce emissions, and the advantages "win-win" measures. and disadvantages of various measures tabled for Governments, donors, and nongovernmental mitigating air pollution-make emissions reduc- organizations have sought to raise public aware- tion easier even with the existing vehicle fleet. ness about emissions in South Asia. Two-stroke engine vehicles may eventually be * The Hydrocarbon Development Institute of phased out in South Asia, to be replaced by Pakistan has distributed pamphlets and comparable but cleaner alternatives that still meet 30 Improving UrbanAirQualiyinSouthAsiabyReducngEmissions from TIo-Stroke Engine Vehicles _-7 Box 6 Reducing emissions and improving performance through free inspection and maintenance clinics in Delhi To reduce emissions, the Society of Indian Automobile Manufacturers (SIAM) and other Indian companies spon- sored voluntary inspection and maintenance clinics for two-wheelers in Delhi in 1999. The clinics, funded in part by the U.S. Agency for International Development, were held simultaneously in four locations in three phases over four weeks. SIAM member companies provided 45 instruments and 200 staff. Major vehicle manufacturers staffed and ran repair and information booths. Instrument manufacturers were on site to check instrument cali- bration and ensure the accuracy of emission measurements. The government of Delhi authorized SIAM to issue "Pollution under Control" stickers and stationed traffic police personnel at the clinic sites. The clinics were widely publicized in the media, with appeals made by dignitaries, celebrities, and top-ranking government officials. The cost of this highly successful program was about US$2.50 per driver. Simple maintenance tasks were performed at the clinic, and booklets on maintenance and fuel-saving driving tips were distributed. Vehicles were first checked for carbon monoxide and hydrocarbon emissions while idling. If the vehicle failed (that is, if carbon monoxide emissions exceeded 4.5 percent of the exhaust gas or hydrocarbon emissions exceeded 9,000 parts per million) it was taken to a repair booth where the carburetor was adjusted and emissions measured again. If the vehicle failed the second emissions test, the spark plugs were cleaned and adjusted and the air filter cleaned. A third emissions test was then run. After testing the vehicle was taken to the safety booth, where the driver received a booklet of safety and maintenance tips. About 80 percent of participating vehicles passed the idle carbon monoxide test; 95 percent of the remaining 20 percent passed the test after minor repairs. Seventy-five vehicles that initially failed the emission tests were tested for fuel consumption. Fuel economy improved from an average of 39 to 47 kilometers per liter after minor repairs, demonstrating the benefits of performing simple maintenance tasks. One of the four clinics had a smoke meter, and smoke measurements were taken of failing vehicles before and after the minor maintenance. Smoke emission levels fell after minor repairs. the social and economic needs of the public. are phased out. Under these circumstances, the Dynamic partnerships among government, importance of promoting good practice in lubri- industry, and the public will be crucial in the cant use in in-use two-stroke engine vehicles development of, and commitment to, achieving cannot be overemphasized. In this "win-win" air quality goals. A transition period is likely, situation vehicle emissions can be dramatically probably a number of years, during which in-use reduced and vehicle maintenance made easier at two-stroke engine vehicles in large urban centers virtually no cost. ANNEX A Health Impact of Air Pollution early all vehicular particulate emissions processes, and poor vehicle and equipment are extremely damaging to public health. maintenance all contribute to particulate emis- Concentrations of total suspended sions. Most particles generated from the particles and particulate matter with an aerody- combustion and condensation of vapors are namic diameter of less than 10 microns (PM10) PM25. Most particles emitted from vehicles have have been found to exceed internationally ac- diameters of less than a micron. Moreover, these cepted guidelines and standards severalfold in particles are emitted near ground level, close to several South Asian cities. Even more damaging is where people live and work. fine particulate matter smaller than 2.5 microns Primary particles are those emitted directly (PM2.5). Other air pollutants from vehicular from a source. Secondary particles are formed emissions that affect public health are lead (where within the atmosphere, mostly from the chemical leaded gasoline is used), carbon monoxide, sulfur oxidation of atmospheric gases. Vehicles contrib- oxides, nitrogen oxides, ozone, and airborne ute to secondary particulate formation when toxins. oxides of sulfur and nitrogen in the exhaust gas are transformed into sulfate-based and nitrate- Particulate Matter based fine particulate matter in the atmosphere. PMIO and PM2.5 remain in suspension in the air Isolating the effects of different types of for hours or days and can travel significant particulate matter is difficult because other distances from the source. These particles enter pollutants-as well as other factors in the environ- the respiratory tract, reaching deep into the lungs. ment, such as changes in temperature or PMIO includes all particles likely to pass through epidemics of infections-also affect health. But a the nose and mouth. PM2.5 includes particles able series of extensive studies, mainly in the United to reach the deeper parts of the respiratory tract, States, has tied changes in particulate concentra- especially the alveolar regions of the lung. Animal tions to changes in a wide range of health studies indicate that ultrafine particles (with indicators, including deaths, changes in lung diameters of less than 0.05 microns) are cleared function, emergency room visits, exacerbation of from the lungs only very slowly and can penetrate asthma, hospital admissions, respiratory symp- the pulmonary interstitium, where they cause toms, and time off from school or work (Holgate inflammation. and others 1999). The largest source of fine particulate formation These associations are stronger for particulate is the incomplete combustion of fossil fuels and concentrations than for other pollutants. The biomass. Low fuel quality, inefficient combustion measurement of particulate-related death has 31 32 Improving UrbanAirQualityin South Asia byReducing Emissionsfrom Twvo-Stroke Engine Vehicles been particularly well studied, and the results are ide can cause people with chronic heart disease to more consistent than those for other indicators. experience chest pain. Very high levels of carbon Although the composition of PM1O can vary monoxide can impair vision, manual dexterity, widely from area to area and over time, the size of and learning ability and cause death. the estimated effects, particularly the effect on Carbon monoxide is a product of the incom- death rates, does not vary greatly with location. plete combustion of fossil fuels. In most cities On the basis of these studies, the impact on public gasoline-fueled vehicles account for most carbon health may be considerably higher in South Asia monoxide emissions. The level of carbon monox- than in the United States because the quality of ide emissions can be reduced by incorporating medical care is lower and people in urban areas oxygenates in gasoline for old vehicles and by spend more time outdoors. hasnd more time uchdmoreserious effetusing oxidation catalvsts in new vehicles. PMl has much more serious effects on health than total suspended particles, which include Sulfur Oxides particulate matter of all sizes. Coarse windblown particles, for example-common in Delhi-are not Sulfur dioxide, one of the oxides of sulfur, causes believed to have a significant impact on health. changes in lung function in asthmatics and Recent studies have indicated that the number of exacerbates respiratory systems in sensitive particles to which a person is exposed could be individuals. Sulfur oxides are formed when fossil more important than the aggregate mass. fuels containing sulfur are burned. These oxides contribute to acid rain and to the formation of Lead secondary particles. The amount of sulfur emitted In cities where leaded gasoline is still used, is directly proportional to the amount of sulfur in airborne lead poses a serious health threat. The the fuel. It can be reduced by treating the fuel, for worst effects appear to be on the intellectual and example, through hydrotreating, or by installing behavioral development of children. There has sulfur removal devices at the point of emission, been much public health interest in this issue such as flue gas desulfurization units at power because of mounting evidence that continual plants. exposure to even low levels of lead, previously considered safe, could have a negative impact on Nitrogen Oxides children's intelligence. Thildren's abpteioenolea from theenvironment Nitrogen dioxide, one of the oxides of nitrogen, The absorption of lead from the environment causes changes in lung function in asthmatics. depends on the chemical and phvsical characteris- Nitrogen oxides are formed during combustion as tics of the lead as well as age, nutritional status, and physiological status. The amount of lead tro the air reacts with ox igh absorbed by the body increases significantly when temperature. Like sulfur oxides, these oxides the stomach is empty. The rate of absorption is contribute to both acid rain and secondary also higher for children than for adults. Some particulate formation. Nitrogen oxides are also evidence also suggests that more lead is absorbed precursors of ground-level ozone. by people with low dietary calcium intake or iron Power plants and diesel- and gasoline-fueled deficiency (World Health Organization 1995). vehicles emit nitrogen oxides. The amount of These findings indicate that poor, malnourished nitrogen oxide formed can be reduced by control- children are particularly susceptible to lead ling the peak combustion temperature-for poisoning. example, by recirculating exhaust gas in vehicles; reducing the amount of oxygen available during Carbon Monoxide combustion; or converting nitrogen oxides to Carbon monoxide is a colorless, odorless gas that oxygen-containing inorganic compounds and inhibits the capacity of blood to carry oxygen to nitrogen-for example, by installing three-way organs and tissues. High levels of carbon monox- catalytic converters. AnnexA -HealthlmpactofAirPollution 33 Ozone but is a complex function of a number of factors Ozone causes photochemical smog and has been that include the ratio of these two precursors. It is associated with transient effects on the human therefore important to collect relevant data and respiratory system, particularly the decline in understand the chemistry of ozone formation pulmonary function during light to heavy exer- before selecting mitigation measures. cise. Gasoline-fueled vehicles are a significant Toxic AiTborne Emissions source of volatile organic compounds, which along with nitrogen oxides are precursors of Toxic emissions from vehicles include benzene; ozone. Ozone abatement is complicated by polycyclic aromatics; 1,3-butadiene; and alde- nonlinear interactions among ozone precursors- hydes. All of these are carcinogens, according to the amount of ozone formed is not directly the World Health Organization, which provides proportional to the ambient concentrations of guidelines for ambient concentrations. volatile organic compounds and nitrogen oxides ANNEX B Improving Particulate Sampling of Two-Stroke Engine Vehicles EA Technology in the United Kingdom to capture sample from the hot exhaust gas before conducted an experimental program to it had a chance to cool to ambient temperature. find a more reliable particulate sampling The flow to the microtunnel was constant; the technique (Smith 2000). The experiment investi- remaining flow to the CVS depended on engine gated two aspects of particulate sampling: conditions. * Whether passing gas through a filter coated The exhaust gases were mixed with filtered with liquid deposit causes any loss of that dilution air in the dilution tunnel (internal diam- liquid. eter 21.5 centimeters), with the CVS pump * Whether significant amounts of oil are lost in providing a constant volume flow through the the sampling pipes into and including the dilution tunnel. A standard regulatory filter constant volume sampling (CVS) system. sample for particulate matter was taken from the dilution tunnel onto 47 millimeter diameter To try to answer the first question, AEA Pallflex type TX40HI20-WW filters. compared the use of an Andersen impactor-in In addition to this method, an Andersen which particles are deposited on filter papers impactor was used to measure particulate emis- without gas passing through the paper-with the sions. The Andersen II Cascade Impactor is standard regulatory filter method. The second designed to measure the mass-weighted size question was investigated by taking particulate distribution of aerosol particles up to an aerody- sample from raw exhaust very close to a motor- namic diameter of about 10 microns. The cycle under steady state conditions and instrument is a multistage, multijet device that comparing the results with CVS measurements. separates particles into size classes based on their A 1974 twin-port, two-stroke, single-cylinder inertia. An impactor stage consists of a series of Jawa 250 cubic centimeter motorcycle manufac- jets over a flat collection medium (filter) at a tured in Czechoslovakia was used for the preset distance. Aerosol passing through each jet experiments. The vehicle had 39,500 kilometers on is directed against the filter, causing the fluid the odometer and no emission control. It operated streamlines to be deflected through 900. Particles with unleaded gasoline at a ratio of 30 to 1 with with high inertia are unable to follow the stream- Castrol Super TT two-stroke oil that met JASO FB lines and impact on the collection medium; and API TC specifications. The lubricant and particles with a sufficiently low inertia follow the gasoline were premixed. streamlines and miss the collection plate. A Horiba microdilution system (MDLT-1300) The investigators used two impactor stages. was installed very near the motorcycle's exhaust The first collected particles with diameters of 35 36 ImprovingUrbanAir QuaKinSouthAsiabyReducingEmissionsfromn Two-StrokeEngine Vehicles 0.3-10 microns. The second collected particles Data were collected over three days (table Al). with diameters of less than 0.3 microns. This Deposits on the filter papers were gray-brown in method differs significantly from the standard color, typical of oil deposits. Solvent extraction on regulatory method because the gas flows around a selection of filter papers removed 98-99 percent the paper instead of through it, eliminating the of deposits. possibility of liquid droplets being bubbled The data from the regulatory and Horiba through the paper because of the gas flow. microtunnel systems were similar, particularly Because the total exhaust volume flow rate when the uncertainty in the microtunnel measure- fluctuates, steady state experiments were con- ments was taken into account. The results suggest ducted to be able to use the data obtained using that condensation along the sampling lines and the Horiba filters. The motorcycle was driven CVS is not a major problem and that the Andersen until reasonably stable conditions were obtained, impactor ields masses about 60 ercent higher and an average over 10 minutes was taken. t y g than the other twvo techniques. The motorcycle itself caused the greatest The CVS flow did not have a significant problem for obtaining reproducible results. i Becase te enine as ustabe, i wasnotimpact on the results within the experimental Because the enine was unstale, it was,no reproducibilitv of the driving conditions. At the feasible to use the equivalent of a dead man's foot on the motorcycle. The steady states thus had to end of the experiments the CVS system was taken be manually driven. apart. There was no evidence of significant Data were also taken at idle, at 30 and 50 fouling by oily deposits in the dilution tunnel, kilometers per hour steady states, and at an although there was a little oily soot in the heat Economic Commission for Europe (ECE) transient exchanger. Fuel consumption from the transient driving cycle. The ECE cycle could not be fol- cycle was calculated to be about 23 kilometers per lowed exactly because the motorcycle was unable liter using a carbon mass balance. to drive the cycle with the required gear changes. The relation between the particulate emissions The cycle was run as an example exercise only. measured by the Horiba microtunnel and regula- Table Al Experimental particulate emission results Andersen Horiba Constant volume Regulatory impactor microtunnel Percent of sampling flow Road speed particulate particulate particulate Smoke particles larger (cubic meters (kilometers (grams per (grams per (grams per opacity than 0.3 Run per minute) per hour) kilometer) kilometer) kilometer) (percent) microns 1 9.0 30 0.098 - 0.080 1 5 - 2 4.4 30 0.116 0.167 - 20 90 3 2.9 30 0.112 0.184 0.100 23 90 4 9.0 30 0.123 0.186 0.126 - 95 5 9.0 30 0.141 0.223 0.129 25 89 6 4.4 30 0.128 0.200 0.117 1 9 87 7 2.9 30 0.125 0.224 0.108 21 84 8 9.0 30 0.081 0.129 0.075 1 3 82 9 4.4 30 0.101 0.149 0.092 1 7 83 11 9.0 0 0.014' 0.026a 0.021 ' 28 84 12 9.0 50 0.056 0.093 0.054 14 78 13 9.0 ECE cycle 0.611 0.984 - - 91 - Not available. a. Emission expressed in grams per minute. Source: Smith 2000. AnnexB-ImprovingTartctlabteSamplingof Two-StrokeEngine Vehicles 37 tory techniques suggests that little sample is lost tory filter. However, under the conditions under to condensation. Uncertainties in exhaust flow which the system was operated, the relation determination mean the two measurements are between the Andersen and regulatory data is not identical, but the ratio between the two linear. Therefore, even if some systematic losses measurements is constant. The absence of sample did occur, the use of the regulatory method would loss is confirmed by the lack of fouling of the CVS provide a satisfactory comparative method: the dilution tunnel by oil droplets. However, there absolute values may not be exactly correct, but the was evidence that the heat exchanger, with its correlation between vehicles and oils would be much smaller diameter tubes, does cause droplet valid. condensation. In the dilution tunnel, whose The Andersen data imply that about 90 percent diameter is 21.5 centimeters, the interaction with of the particulates (by mass) have diameters of the walls is minimized; in the heat exchanger, more than 0.3 microns. These are likely to be oil however, the interaction with the walls causes droplets, as suggested by the color of the deposits droplet condensation. This does not affect particu- and the solvent extraction results, which imply late measurements, which are made before the that 98-99 percent of the deposits are from oil. heat exchanger. The higher results from the Andersen impactor seem to suggest loss of sample from the regula- ANNEX C Analytical Tools for Cost-Benefit Analysis egulatory decisions for the management tries. Vehicular emission factors are a function of i of urban air quality should be based on fuel quality-for example, the level of sulfur in :',objective assessment of scientific and gasoline and diesel fuel-and vehicle technol- technical evidence and thorough cost-benefit ogy-for example, the level of maintenance and analysis of alternative air quality improvement the nature of exhaust treatment devices. The U.S. strategies. Timely information about air quality, Environmental Protection Agency's highway emissions, and health and other benefits of vehicular emission factor model contains a fairly reducing emissions is needed to conduct cost- comprehensive list of vehicular emission factors, benefit analysis. but the data do not reflect the condition of ve- Air quality monitoring and reporting need to hicles in developing countries. be upgraded to internationally acceptable stan- Several software programs are available to dards and made available to the public daily. build emissions inventories for both mobile and Reliable and complete inventories of emissions stationary sources. The Decision Support System from different sources (domestic, industrial, for Integrated Pollution Control is based on the different transportation modes, resuspended dust) World Health Organization's emission factors. are crucial for identifying priority areas for The International Petroleum Industry Environ- interventions. Air quality modeling then needs to mental Conservation Association's Urban Air be conducted based on the monitoring and Quality Management Toolkit is one of only a few inventory data to identify the main sources of models that takes into account the effects of fuel ambient pollution in the areas where the largest composition on emission factors. It is linked to a number of people are at risk. The health and other model that calculates incremental costs for benefits of reducing emissions then need to be different mitigation options. computed and compared for different mitigation The World Bank has recently built an Excel measures. spreadsheet-based transport emissions inventory The reliability of the emissions inventory program, VAPIS (Vehicular Air Pollution Informa- depends on the accuracy of the data on emission tion System). The program computes past and factors and consumption of fuels used in different future vehicular emissions as a function of vehicle sectors. But reliable data on emissions by the type, year, and fuel used for several pollutants. It transport sector are scarce in developing coun- projects future vehicle growth and emissions. 39 ANNEX D Reports Prepared under the South Asia Two-Stroke Engine Initiative Energy and Environmental Analysts, Inc. 1998. Market Description and Policy Analysis." "Technology and Policy Options to Control November 3. Three-Wheeler Emissions in Dhaka." January. South Asia Environment Sector Management Loksha, Victor. 1997. "An Analysis of the Electric Unit. 1998. "The Cost of Environmental Vehicle Option Based on the Experience of the Remediation in India: The Example of Air Electric Tempo Three-Wheelers Piloted in Pollution by Two-Stroke Engine Vehicles." Nepal and a Similar Project Proposed in February 23. Bangladesh." October 27. Xie, Jian, Jitendra J. Shah, and Carter J. Brandon. . 1997. "Finding Alternatives to Polluting 1998. "Fighting Urban Transport Air Pollution Two-Stroke Engine Vehicles in South Asia." for Local and Global Good: The Case of Two- April 29. Stroke Engine Three-Wheelers in Delhi." April. Matskovski, Anton. 1997. "Reducing Emissions from Two- and Three-Wheelers in India: 41 Notes 1. Another pollutant of concern is lead, although 6. Two-stroke engine vehicles produce more lead in gasoline has been phased out in noise than four-stroke gasoline engine Bangladesh and India. Pakistan and Sri Lanka vehicles, but four-stroke diesel engines are are two countries where leaded gasoline is noisier than either type of gasoline engine. still widely used. 7. Lead is added to gasoline as an organic 2. If leaded fuel is used, two-stroke engines emit compound to improve its combustion organic lead, which is much more damaging characteristics. to public health than the inorganic lead 8. In India most electricity is generated by formed by the full combustion of lead burning coal, which emits about twice as additives. much carbon dioxide as natural gas per unit 3. Tests done at ARAI (the Automotive Research of electricity generated. Thus where coal is Association of India) in the fall of 2000 burned, switching to electric vehicles will not indicate emissions reductions of this necessarily reduce greenhouse gas emissions. magnitude, but require further analysis. 9. The research octane number is a measure of a 4. As the size of the program-and subsidy- gasoline's resistance to self-ignition grew, the government could not afford to (knocking) when vehicles are operated at low continue bearing the cost. When the subsidies speed corresponding to city driving were reduced the use of CNG fell conditions. dramatically. Without subsidies CNG use 10. The motor octane number is a measure of a proved to be unsustainable. gasoline's resistance to self-ignition 5. This is also because the standards for (knocking) when vehicles are operated under hydrocarbon emissions in 2003 are twice as highway driving conditions. stringent for two-stroke than for four-stroke 11. There is no consensus on the best type of two-wheelers. battery for the future. 43 References and Selected Bibliography Auto/Oil Air Quality Improvement Research Huang, H. H., M. H. Jeng, N. T. Chang, Y. Y. Peng, Program. 1997. Program Final Report. J. H. Wang, and W. L. Chang. 1993. ARAI (Automotive Research Association of "Improvement of Exhaust Emissions on Two- India.). 1998. "Monitoring of In-Use Vehicle Stroke Engine by Direct-Injection System." SAE Emissions." Paper presented at the Workshop Paper 930497. on Integrated Approach to Vehicular Pollution International Energy Agency. 1997. "CO2 Control, April 16-18, Delhi, India. Emissions From Fuel Combustion." Diskette Caines, A. J., and R. F. Haycock. 1996. Automotive Service Documentation, International Energy Lubricants Reference Book. Warrendale, Penn.: Agency, Organisation for Economic Co- Society of Automotive Engineers, Inc. operation and Development. Paris, France. Chan, Lit-Mian, and C. S. Weaver. 1994. Motorcycle Iyer, N. V. 1999. "Technology for Cleaner Two- Emission Standards and Emission Conitrol and Three-Wheelers: Achievements and Future Technology. Department Papers Series 7, Asia Challenges." Paper presented at the Confederation of Indian Industry Technology Techinical, Department, WorldBank,Summit and Platform, October 28-29, Hyderabad, India. Curnming, R. B. 1997. "The International Perspective,R."B.1997"The International Asso. 2000. "Emissions and Control Options for Perspective." International Associationfor Two-Stroke Engines in India." Paper presented Natural Gas Vehicles Newsletter 45. worop on mlin from at the Workshop on Pollution from Danielson, Eugene. 1978. "Particulate Motorcycles: Issues and Options, March 9, Measurement Motorcycle Test Results." NTIS World Bank, Washington, D.C. Publication PB80-115983. Ann Arbor, Mich.: Kirchberger, R. S. 2000. "Future Prospects of Two- U.S. Environmental Protection Agency. Stroke Engines and Possible Technical Faiz, A., C. S. Weaver, and M. P. Walsh. 1996. Air Solutions for East/South Asian Markets." Pollutionfrom Motor Vehicles: Standards and Paper presented at the Workshop on Pollution Technologiesfor Controlling Emissions. from Motorcycles: Issues and Options, March Washington, D.C.: World Bank. 9, World Bank, Washington D.C. Holgate, S. T., J. M. Samet, H. S. Kore, and R. L. MECA (Manufacturers of Emission Controls Maynard, eds. 1999. Air Pollution and Health. Association). 1999. "Emission Control of Two- London: Academic Press. and Three-Wheel Vehicles." Washington, D.C. 45 46 Improving Urban Air Quality in South Asia by Reducing Emissionsfrom Two-Stroke Engine Vehicles Moulton, Peter, and Marilyn Cohen. 1997. Smith, Allan P. 2000. "Assessment of Particulate "Introducing Electric Vehicles in the Sampling for Two-Stroke Vehicles." AEA Developing World." Paper presented at EVS-14 Technology Report submitted to the World International Electric Vehicle Symposium, Bank, Washington, D.C. December, Orlando, Florida. Southwest Research Institute. 1973. "Exhaust Palke, D. R., and M. A. Tyo. 1999. "The Impact of Emissions from Uncontrolled Vehicles and Catalytic Aftertreatment on Particulate Matter Related Equipment using Internal Combustion Emissions from Small Motorcycles." SAE Engines: Part 3, Motorcycles." San Antonio, Paper 1999-01-3299. Tex. Radian International. 1998. "Particulate Matter World Health Organization. 1995. Environmental Abatement Strategy for the Bangkok Health Criteria 165: Inorganic Lead. World Health Metropolitan Area: Final Report." Organization, Geneva. Selected World Bank Titles of Related Interest Environment Department Papers No. 9 Ayres, and Dixon, Economic and Ecological Benefits ofReducing Emissions of Sulfur Oxides in the Sostanj Region of Slovenia No. 18 Kjorven, EnvironmentalAssessment: Challenges and Good Practice No. 28 Lovie, Facing Pollution Abatement: Theory-Practice No. 46 Lovei and Weiss, Environmental Management and Institutions in OECD Countries No. 63 Hagler Bailly, Inc. and others, The Effect of a Shadow Price on Carbon Emissions in the Energy Portfolio of the World Bank: A Backcasting Exercise No. 70 Keene, Developing a Culture of Industrial Environmental Compliance: A New Approach No. 71 Segnestam, Environmental Performance Indicators: A Second Edition Note No. 74 Goodland, Social and Environmental Assessment to Promote Sustainabilitv: An Informal Viewfrom the World Bank Non-serialpublications Hughes, Ackermann, Keene, Lvovsky, and Nielsen, Can the Environment Wait?: PrioritiesforEastAsia Johnson, Liu, and Newfarmer, China 2020: Clear Water, Blue Skies: China's Environment in the New Century World Bank, Greening Industry: New Roles for Communities, Mar kets, and Governments Selvam, Kapoor, Modak, and Gopalan, India: Review of the Effectiveness ofEnvironmental Assessment in World Bank- Assisted Projects THE WORLD BANK 1818 H Street, N.W. Washington, D.C. 20433 USA Telephone: 202.477.1234 Facsimile: 202.477.6391 Internet: www.worldbank.org South Asia Region internet: http:/lwblnl018.worldbank.org/sar/sa.nsf