WhyDelhiʼs clean air fight needs more than a blanket ban on old vehicles
Starting July 1, refuelling of old vehicles (15-year-old petrol and 10-year-old diesel models) has been banned in Delhi to implement the mandate from the Commission for Air Quality Management. However, in the face of public fury, the Delhi government has put this programme on hold, citing “operational and infrastructural challenges”. While the fate of 62 lakh overage vehicles remains uncertain, questions have emerged around the purpose and the method of enforcing such measures for clean air. Why is it necessary to phase out old vehicles — especially old private vehicles? And is a sweeping age-based ban the only answer? Why ageing eets are a concern There is a reasonably strong case for replacing older vehicles with clean and near-zero emissions vehicles. The older vintages were designed under signicantly weaker emission norms and emit far more pollution than those complying with the current Bharat Stage VI (BS VI) emissions standards. For instance, a BS III diesel car — over a decade old in Delhi — emits up to 11 times more particulate matter (PM) than a BS VI vehicle. A very old heavyduty diesel truck meeting BS I norms can spew 36 times more PM than one meeting BS VI norms. Wear and tear only worsen these emissions. This is not fully captured by the current Pollution Under Control (PUC) certication system which relies on idle engine emissions. This method fails to measure pollutants under varied real-world conditions such as acceleration or variable speed of driving. Evidence also shows that a small fraction of vehicles is responsible for a disproportionate share of emissions. For instance, a national estimate by the International Council on Clean Transportation shows that pre-2003 vehicles constituted less than 20% of total vehicles but accounted for nearly half of all vehicular particulate emissions and a third of nitrogen oxide emissions in 2011. The accumulating old eet can thus lock in enormous pollution. A rigorous emissions monitoring system should target such vehicles. That said, even newer vehicles can become high emitters if poorly maintained or malfunctioning. These too must be identied and addressed. There are also material benets to retiring End-ofLife Vehicles (ELVs). A joint report by theInternational Energy Agency and NITI Aayog found that recycling ELVs and recovering critical materials can reduce raw material costs by up to 40%. However, Indiaʼs current recovery rate stands at 70- 75%, well below the global benchmark of 85-95%. Moving beyond age-based bans While the clean-air benets of eet renewal are clear, a standalone and a blanket age-based ban is not a scalable and sustainable strategy. A more eective strategy would combine vehicle age with other indicators such as tness, maintenance, and emissions performance. This can be complemented by targeted age-based bans as needed. The 2021 scrappage policy by the ministry of road transport and highways (MoRTH) denes ELVs as those without valid registration or deemed unt through Automated Testing Stations (ATS). While all commercial vehicles have been mandated to undergo tness tests only in the ATS nationwide, the deadline has been extended. But Delhi can lead by enforcing ATS testing for commercial vehicles. However, stricter ELV criteria and better emissions tracking are also needed for private vehicles. More advanced on-road monitoring, like remote sensing, is needed to go beyond the PUC programme. Emission monitoring machines placed by the roadside can eciently identify the worst polluters. Central rules need to be notied immediately to implement this. The scrappage policy can start with the worst polluters — like old diesel trucks and commercial vehicles — and gradually include other ELVs. To make this work, nancial incentives will be required. The MoRTH policy allows for tax concessions, which states like Delhi have begun using. These can be strengthened with manufacturer buyback schemes and linked to cleaner or electric vehicle purchases to maximise emission gains. It is, however, clear that if tness testing, emissions performance, selective bans with nancial incentives are to serve as viable alternatives to blanket age-based bans, then emissions monitoring must be both advanced and stringent to identify ELVs eectively. Smart on-road monitoring and disclosure mechanisms must be part of the solution. Currently, it is evident from the VAHAN database of MoRTH, that as of July, out of 8.7 lakh vehicles tested in the ATS nationally, only 304 vehicles have been ocially declared as ELVs. Finally, the public outcry over age-based bans also reects a deeper issue: the lack of adequate mass transport options. Delhi needs massive augmentation of public transport and mobility systems, along with vehicle restraint measures like parking management area plans with increased parking pricing, to restrain personal vehicle usage. Roychowdhury is executive director, research and advocacy, Centre for Science and Environment