Over the past two decades, diesel engines have improved so much that they have become very popular. They are no longer the sluggish and noisy smokers of the past, but with the common rail technology, are now peppy and fuel efficient. Though they are more expensive to buy, they also enjoy the benefit of lower prices. Actually, these lower prices are because of lower taxes, because clean low sulfur diesel now costs more than petrol at the refineries. Diesel engines are blamed for much of the world’s atmospheric pollution with the result that carmakers worldwide are now resigned to abandoning diesel engines.
The minister of Road Transport and Highways recently announced that India would skip Bharat Stage (BS) V and jump from the existing BS-IV to BS-VI norms from April 1, 2020. This has shaken up all of India’s automakers because the estimated cost of engine upgradation required to meet these new norms would make them unacceptably expensive.
The high compression diesel engines cost more to make and even this cost had gone up when the high-pressure Common Rail fuel injection systems were introduced to increase engine efficiency. Now turbochargers, particulate filters, Catalytic Convertors, NOX traps and several other engine modifications will be necessary. Thus, a big difference in the costs of a typical petrol and diesel-powered model would make the latter too costly.
Not surprisingly, Maruti Suzuki has publicly announced that it will discontinue diesel engines from April 1, 2020 and all the other carmakers will probably follow suit.
The huge cost differential between the price of diesel and petrol had been the main reason for the popularity of diesel engines. This price gap has, however, been dwindling rapidly over the past few years and is likely to narrow even further. If there is no cost-benefit in the price of the fuel, there will be no reason to buy a more expensive diesel-engined car. Diesel will, however, continue to be needed for trucks, tractors and pump sets as well as for a huge fleet of diesel-engined cars that are still plying on the roads.
Europe, the world’s largest diesel car market, has also been feeling the pinch. Diesel engine cars had accounted for 42 per cent of German car sales in 2017 despite the cost of diesel being slightly higher than the cost of petrol. But, because diesel was about 20per cent more efficient, diesel cars gave more kilometers per litre. The strong sentiments concerning pollution had, however, reduced their numbers to 36 per cent one year later.
Volvo has completely stopped diesel car sales. Toyota stopped the sales of diesel models in Europe last year. Porsche says that it will concentrate on petrol, electric, and hybrid engines. While, Renault, Peugeot, Citroen, Fiat-Chrysler, Cadillac, Suzuki, Kia, Mitsubishi, Bentley and others have all switched to petrol.
All the carmakers can see the writing on the wall and are focusing their energies on electric or hybrid petrol cars. Automakers are also working on CNG or LPG, but though these are less polluting, they are still fossil fuels that leave a carbon footprint. Several automakers also advocate hydrogen cars, but these need a network of fuelling stations. Almost all car companies are therefore investing heavily in electric car technologies.
As compared to about 20,000 parts in the power train of an internal combustion engine, an electric car motor has just 20 and is much smaller, lighter and cheaper to make except for the high cost of the battery pack. But, that too is steadily coming down.