'Diesel cars will probably have a slow decline'

Furquan Moharkan , December 20, 2015, DHNS

Daniel Sperling is Professor and Director of the Institute of Transportation Studies at the University of California, Davis. In a telephone interview withFurquan Moharkan of Deccan Herald, he said that the recent regulatory actions pertaining to diesel and headline- grabbing events are a turning point in history, and that it can cause a slow decline in diesel consumption.

The Delhi government recently decided that private vehicles with odd and even registration numbers will ply on odd and even dates from January 1, 2016. What is your comment on this?

This approach is symbolically important and might have some impact. However, people will buy a second cheaper (and dirtier) car for the alternate days, or borrow someone else’s car.  

And for some people who do not have good access to public transport, it can be difficult.What is your opinion on the recent crackdown on diesel vehicles by the National Green Tribunal and the Supreme Court?

The problem is twofold: older diesel vehicles are very polluting; and the regulators are not requiring modern diesel engines. Modern diesel engines are very clean  as they approach zero emissions. 

But these very clean diesel engines cost a little more, and require strong regulators and regulations. Even Europe is somewhat challenged, with diesel emissions much higher than those in the US — even though the cars are made by the same automakers.
 
Is this the beginning of the end of diesel, especially for cars, due to combination of regulatory actions that are specific to diesel and headline-grabbing news like the Volkswagen Emissions Scandal?

This marks a turning point. Some cities in Europe have turned against diesel, including Paris. Diesel cars will probably have a slow decline, but the end is still very far off.

Will the crisis confronting to diesel lead to the collapse of automobile industry, given that diesel vehicles make up 50 per cent of major market economies like EU and India?

This will not lead to a collapse of the industry. Almost all companies that sell large numbers of diesel cars also sell gasoline cars. As diesel begins a slow decline, a few companies will struggle to shift their focus. 

But the bigger challenge for these companies is the aggressive tightening of greenhouse gas, and fuel efficiency standards in all the major markets(EU, Japan, China, and US), except India.
 
How will the phasing out of diesel vehicles impact the purchasing power of car buyers, given that diesel is cheaper than petrol?

Diesel fuel costs about the same as gasoline fuel to produce, and diesel engines tend to cost more than gasoline engines. 

The advantages of diesel engines are its greater energy efficiency and greater durability. Diesel fuel prices are less in many markets because governments are subsidising the diesel fuel (relative to gasoline) as a way of supporting trucking (since diesel engines are widely used in trucks), and agriculture (where diesel engines are often widely used).
 
How has the Volkswagen Emissions Scandal impacted the general outlook on diesel as a fuel?

 I think it has slightly tarnished its reputation, but most people realise that it was one company that cheated. Other diesel cars are much cleaner and other companies have not been cheating.
 
If all the diesel vehicles in the world are banned overnight, will the world’s pollution and emission problems end? If not, why single out diesel for penalties?

It won’t happen. In any case, everyone would switch mostly to gasoline (and natural gas and biofuels and electricity, in some cases).
 
Can diesel be cleaned up and made safe to use? 

Absolutely yes. Modern diesel engines are 98 per cent cleaner than uncontrolled diesel engines, and essentially the same as very clean gasoline engines. 

All new modern combustion engines are now close to zero emissions of local pollutants  (NOx, PM, CO, Sox), though still high emitters of CO2.