Air

Three-wheeled devil on diesel

Diesel three-wheelers designed to emit more than diesel cars must go off the road to cut toxic exposure

 
By Anumita Roychowdhury
Last Updated: Monday 10 December 2018
Air Pollution
A diesel three-wheeler in Gurugram. Credit: Manas Fuloria A diesel three-wheeler in Gurugram. Credit: Manas Fuloria

When old diesel cars and diesel taxis are being booted out, and big diesel cars and SUVs are allowed to enter the market of Delhi and the National Capital Region (NCR) only after paying a pollution charge, why are diesel auto-rickshaws still messing around in towns of larger NCR and beyond? These three-wheeled devils that are widely used for point-to-point shuttle service across cities of India, are inherently designed to emit several times more toxic pollution compared to most other vehicles on the roads. What makes them worse is their highly toxic, cancer-causing fumes that are dangerous to human health. Nationally, their market share is almost equally divided between diesel and petrol.

Why has this dirty and noxious segment escaped regulatory scrutiny? In fact, the newly notified Supreme Court-directed Comprehensive Action Plan (CAP) has asked for expansion of CNG programmes including the auto fleet and sought introduction of battery-operated zero emissions para-transit as feeders to improve last mile connectivity in Delhi and NCR. Except Delhi and couple of NCR towns that have restrained their use, these vehicles have stirred strong public concern in NCR cities as in Gurugram. Clearly, the intent and the principle of the CAP direction have not catalysed regional or national policy action.

Toxic marauders

Their rampant usage across the country shows how little the public health dangers posed by these little devils are understood. A diesel three-wheeler emits much higher particulate matter compared to its petrol and CNG counterparts. It is also designed to emit higher emissions than even diesel cars! Under the current emissions standards of Bharat Stage IV (BSIV), a diesel auto is legally allowed to emit 1.7 times higher particulate matter and 1.3 times higher NOx+HC than a BSIV diesel car.

This gap with diesel cars will further widen under the more advanced BSVI regulations that will be enforced within two years. Even after meeting BSVI emissions standards, a diesel three-wheeler will emit close to 6 times higher particulate matter and two times more nitrogen oxide compared to a BSVI diesel car. The big concern is the very high on-road and in-vehicle toxic exposure from these vehicles.

What makes them so foul?

These three-wheeled-vehicles are powered by small, single-cylinder diesel engines of less than 500 cc displacement; (if this engine size is exceeded, rules for four-wheelers will apply under the Central Motor Vehicle Rules). Experts point out that these small engines with unstable emissions and high exhaust temperatures limit the scope of application of advanced and effective after-treatment systems that are otherwise used in other diesel vehicles. These vehicles meet emission standards mostly through improved calibration and optimisation. Most solutions used for larger engines are often not adaptable in these small engines. None of these diesel models use the systems that are widely applied in cars, namely, automatic fuel injection timing control, catalytic converters or exhaust gas recirculation. These will largely play around with the optimisation of combustion, automatic ignition timing, friction reduction, improved air filters and lubricating oil. Also, given the price sensitivity of this market, expensive solutions are not possible. 

Under the advanced BSVI regime, when all testing parameters for all other vehicle segments will improve significantly, three-wheelers will be subjected to the same archaic testing systems and requirements that are much less exacting like being tested on the much less rigorous and older Indian Driving Cycle. Imagine how high the real-world emissions from these vehicles on the road therefore will be. Each of these diesel three-wheelers will be much worse than diesel cars.

Side step and leapfrog

Yet, the three-wheelers or the auto rickshaw segment is the most amenable candidate for the big jump to zero emissions electric-mobility. In fact, the first phase of e-mobility in India started with the auto segment. According to an October 2017 forecast of the EREP Market Research Series, of the total estimated future electric fleet size, (if represented as total battery storage capacity), the overall EV market for battery storage in India is likely to be 4.7 GW in 2022, and over 60 per cent of this capacity will be driven by E-rickshaws batteries. Such spontaneous change of such scale in the informal market is unknown in advanced markets.

If such opportunities for transition to clean fuels and a zero emissions mandate already exist, why are diesel autos being pampered and allowed to continue to lock in pollution and ill-health? Diesel three-wheelers do not deserve leniency on the grounds of being a “poor person’s vehicle” as the low- and middle-income groups suffer the consequence of high exposure and ill-health the most. School- going children also use these vehicles. Three-wheelers are para-transit and therefore, high mileage vehicles and responsible for high local exposure. Instead, provide suitable incentives to the vehicle owners to replace them with cleaner vehicles. Acknowledge the problem and act on it quickly before more damage is done.  

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