TOWARDS INTEGRATED APPROACH

Containment of vehicular pollution requires an integrated approach, the essential components of which include the following :

1. Improvement of public transport system (e.g. urban buses)

2. Optimisation of traffic flow and improvement in traffic management (e.g. area traffic control system, no-traffic zone, green corridors, removal of encroachment on roads, regulation of construction activities and digging of roads).

3. Comprehensive inspection and certification system for on-road vehicles.
4. Phasing out of grossly polluting vehicles.

5. Fuel quality improvement (e.g. benzene and aromatics in petrol, reformulated gasoline with oxygenates/additives, reduction of sulphur in diesel).

6. Tightening of emission norms (e.g. EURO-IV by 2005)

7. Improvement in vehicle technology (e.g. restriction on the 2 stroke engines, emission warranty, on-board diagnostic system).

8. Checking adulteration of fuel.
9. Checking evaporative emissions from storage tanks and fuel distribution system.

 

According to an estimate made by RITES, a modal split of 70-75% infavour of public transport needs to be planned for the city of Delhi. Presently, the modal share of public transport (Bus) is 62 percent. Along with the increase in number of buses, the passenger capacity should also be increased and the engines should conform to urban design. The existing circular ring railway network also requires to be improved. These measures will meet the immediate requirements since the mass rapid transport system (MRTS) will take some years to materialise.

Traffic Management System

Well planned Traffic management system results in better mobility level on road by providing higher journey speeds and reduced delay at intersection thereby bringing significant reduction in fuel consumption and emission. Automatic traffic control, signal optimisation, tidal flow and removal of encroachments are among the important components of traffic management system. This will reduce the congestion and consequently pollution. Frequent digging of roads and construction work also leads to congestion and pollution, which can be minimised through proper coordination with traffic police.

Comprehensive Inspection and Certification System

It is a system to reduce the pollution by requiring regular inspection and maintenance of motor vehicles already plying on roads. It identifies those in-use vehicles that need maintenance and repair because they pollute more than the new vehicles. The system helps in reducing the air pollution. Such system is widely used in other countries and it has been possible to reduce about 30-40% of pollution loads by proper inspection and maintenance of vehicles. Such facilities for thorough inspection and maintenance of vehicles are required in different parts of the country.

Phasing Out of Grossly Polluted Vehicles

Pre-1990 vehicles emit more than ten times pollutants than the vehicles meeting Euro I norms (India 2000 norms). In Delhi, more than 15 year old commercial vehicles are not allowed to ply on roads. Similarly, de-registration of all older vehicles should be made effective so that the grossly polluting vehicles are phased out.

Fuel Quality Improvement

Benzene and aromatics in petrol

Due to high level of benzene in atmosphere, benzene content of gasoline needs to be reduced to 1% (v/v) or lower as in other countries. With the reduction of benzene in gasoline (<1%) it is possible to achieve significant reduction in benzene emission from exhaust. Benzene and PAH emission also depend upon the aromatic content of gasoline. Therefore, in addition to reduction of benzene, it is also necessary to reduce the aromatic content in petrol.

Sulphur Content in Diesel

Sulphur in diesel has direct effect on SO₂ and particulate emission and indirectly on other pollutants due to its poisoning effect on catalytic converter. In European countries, sulphur content in diesel has been reduced to 0.05% from 1996 and it will be further reduced to 0.005 from the year 2000.

Reformulated gasoline

Reformulated gasoline with the use of oxygenates and additives etc. help reducing pollution load from on-road vehicles. According to a study commissioned by CPCB, 3-5% ethanol can be used in petrol without affecting the engine performance and with the attendent benefits in terms of emission control.

Tightening of emission norms

The emission norms effective from 2005 need to be further tightened to offset the increase of pollution load due to exponential growth of vehicles. It is time to bridge the gap between Euro norms and Indian norms. Euro IV norms for petrol vehicles and diesel passenger cars and Euro III norms for heavy diesel vehicles may be a preferred target for 2005.

Improvement in Vehicles

In India, majority of vehicles is of two stroke engines. Although the two stroke engine technology for 2 or 3 - wheelers has been upgraded to some extent there is not much improvement in control of hydrocarbons and particulate (due to combustion of lube oil). Hence, it is necessary to consider as to whether 2-stroke technology should be replaced by 4-stroke technology for reducing the emission specially in terms of hydrocarbons and particulate matter apart from increased fuel efficiency in 4-stroke engines.

On Board Diagnostic System

The On Board Diagnostic System (OBD) electronically records the fault and their causes in combination with various Diagnostic Strategies to enable vehicle owner / driver to take corrective action. This is one of the requirements of emission regulation in USA and it will be followed in Europe from year 2000 which will be a part of Euro III norm for 2000.

Checking Fuel Adulteration

Adulteration of fuel plays a major role in emission of pollutants from on roads vehicles. Effective measures are required to prevent adulteration of fuel.

Evaporative Emission Control

To minimise evaporation losses of fuel and consequent pollution, adequate preventive steps need to be taken during storage, loading, unloading and distribution. Vapour recovery system in the filling stations is yet another important measure for reducing evaporative losses.

Table 5 Indian and EURO Norms for Petrol Driven Passenger Cars

         2. In case of Euro III & Euro IV COP = type approved norms
 
Table 6 Indian and EURO norms for Diesel driven Passenger cars

• In case of EURO II and EURO III type approved norms = COP norms.
• In India there is also option for testing with engine dynamometer (in g/KWH) as given in Table 3 as these come under Diesel Light duty vehicles GVW<3.5 tons.
• In European norms Passenger Cars refers to Passenger Cars with seating capacity less than 6 and GVW less than 2.5 tons.

Table 7 Indian and EURO norms for Diesel Light duty Vehicles < 3.5 tonnes

2 = EDC + EUDC

3 = Indian Driving Cycle

Table 8 Indian and EURO norms for Diesel Vehicles > 3.5 tonnes

  Table 10 Comparision of Different Driving Cycles for Passengers Cars