Not surprisingly, given how the Delhi government has demonised cars, the Supreme Court did not lift the ban on registration of large diesel vehicles in the National Capital Region (NCR), but in asking diesel-car manufacturers for data to back their claims, an important window has been opened for data-driven logic. Even after newer diesel technology, diesel may pollute more than petrol does—that’s why advancing the date for better fuel is critical—but auto-makers are arguing that larger engines of some manufacturers pollute as much or even less than some smaller engines. Which is why it must be mandatory for each model of vehicle to make public its emission levels—if the SC still decides to ban larger diesel engines, it has to also ban smaller engines, more so given there are many times more smaller diesel engines in the NCR. Making public the data on each model’s emission will also make it clear that, rather than banning new registrations, it is better to take action on older vehicles which are more polluting and far outnumber the newer ones which, by virtue of better technology, pollute less.
The fact that the SC has banned entry of trucks into Delhi from another four entry points—it had banned entry from two points earlier—also makes it clear that the solution to Delhi’s pollution problem does not lie in the odd-even solution. Indeed, as the IIT-Kanpur study shows, vehicles contribute just 9% of the PM10 pollution in Delhi—20% of PM2.5. Within this, trucks are responsible for 46% and two-wheelers—that Delhi chief minister Arvind Kejriwal has not included in his odd-even scheme—account for a third of the emissions.
With no significant dip in PM 2.5/10 levels (see our page-1 graphic) since the odd-even policy was implemented, at some point, Kejriwal needs to explain why he pushed the scheme so aggressively when the IIT-Kanpur report made it clear cars weren’t the real problem, why two-wheelers were left out despite causing more pollution due to their vastly larger population and, more important, how the scheme is to be run when schools are re-opened and the buses seconded from them have to be removed from the fleet available to the general public. Strict monitoring is also required to see the Delhi government meets its commitments on paving roadsides—the largest source of particulate matter pollution—and checking construction-related pollution.