Delhi’s bar on cars: Using a sword instead of a scalpel for surgery

Enough has been written (mostly against) the idea to limit cars in Delhi, by license plate.  Will it work? Can you enforce it? Will it lead to more sales of alternate number of cars? And, most importantly, are alternatives such as public transport ready, especially considering issues of first/last mile?

Much of the pollution comes from a subset of vehicles (aka the 80:20 rule), especially diesel/commercial vehicles, and we should figure out the type, make, model, year, etc. of worst polluters.  Because we’ve failed at properly identifying the worst offenders and enforcing even existing rules, are we left with no other option than a sword instead of a scalpel?

The Government policy of “supporting” diesel is partly to blame, compounded by poor maintenance, overloading of commercial vehicles, and adulteration in fuel.  Out of the worst offenders I’m sure some of them even have a PUC (pollution under control) sticker.

Testing, if done at all, is flawed, and is strictest only for petrol 4-wheelers, which are not the worst offenders!   Tests also don’t subject vehicles to load (notice how pollution is far worse when vehicles accelerate or struggle to cross a flyover?), and most inspection stations I have visited have flawed equipment or procedures, just to ensure a sticker can be given.  This is before the issue of poor enforcement, let alone corruption.

The first question that needs scientific analysis is what is the cause of most of this pollution?  Major sources vary, and we have to remember that some pollution is very, very localized.  In addition to vehicles, we can have coal power plants (from kilometers away), diesel generators, other industry, fuelwood, and burning of waste.

If we’re targeting reduction of pollutants, perhaps the first place is to ban vehicles that don’t have modern catalytic converters, as well as 2-stroke engines.  Of course, this may place an undue burden on some segments of society, so before we ban anything, we should first understand who is impacted, and what options are there for minimizing their pain.  If I’m a vehicle-owner, spending 15% of my costs on road-taxes (registration), I would surely demand 50% back if I can’t use the vehicle half the time!

Technology is a longer-term solution, including congestion pricing.  In the current plans, CNG has been allowed.  Why don’t we encourage hybrid electric vehicles (even before plug-in electric vehicles)? While the carbon implications of electric vehicles are a wash (our generation is coal heavy), even non-plug-in hybrid vehicles are proven to reduce local air pollution dramatically.

Trees aren’t the solution (shocker!).  Trees don’t absorb particulates (only some amount sticks to them), and they act as a barrier more than anything else.  Studies show adding trees could make localized pollution worse, even if other areas are better off.

Pollution is a big deal, necessitating change.  In addition to fixing root cause problems, we have to validate any policy via experiments, that too with granular data.  A daily single number (or color code) for a city only tells part of the pollution picture.  Already we have time restrictions on trucks.  Are there studies measuring how much pollution jumps at these times, and where?

Reducing almost half the vehicles will certainly help congestion, which has been a bigger driver in many countries than pollution reduction. But we have to recognize that such benefits may come with disproportionate burden on selected segments of consumers.