Two weeks ago, Volkswagen announced it was recalling 500,000 of its diesel-engine cars in the US and 11 million worldwide. It admitted to having cheated the US emissions inspection system by including a programme in the cars’ computers that would detect when the inspection was being performed and only then turn on the pollutants’ filtering device.
At all other times, the cars would run without the filter, resulting in huge emission amounts. What a cheat!
All kinds of questions arose in my mind, including how such a scheme could be devised and implemented, how many people knew (for several years), and why Volkswagen resorted to such a devious manoeuvre, risking its previously sterling reputation. (Indeed, within a week of the revelation, the company’s shares lost about a third of their values.)
According to Volkswagen, only a small number of its staff knew of the scheme, and they have now been suspended, pending an investigation. Its CEO resigned and was replaced by the CEO at Porsche. More importantly, it turns out that Volkswagen not only cheated by setting up that software, it tried to cover up the scheme last year when the US Environmental Protection Agency brought to its attention the overly high emissions of its diesel-engine cars and threatened to ban them.
Volkswagen then announced a recall of the cars, promising to “fix” them, knowing full well what the problem was.
Why did Volkswagen resort to such a deceitful approach? Couldn’t the pollutants just be captured by the filter and removed?
Diesel engines are different from those running on gasoline in several regards. They have better fuel efficiency (1.5 times more mileage per litre compared to gasoline); they are sturdier, because the diesel fuel burns at very high temperatures and pressures; and they give more ‘pull’ (torque) at low power.
That is why they are almost everywhere used in trucks and buses. They are economical, and they last longer; thus, in many countries, they are liked by customers — as long as they drive vigorously enough.
But diesel engines produce lots of pollutants. In the past, we used to see diesel cars and trucks produce so much dark exhaust, smoke and soot that contain high amounts of sulfurous compounds. Carmakers solved this problem, and this kind of diesel byproduct is now trapped and removed.
The other type of diesel pollution — the one that has not been solved — is the infamous NOx (nitrogen oxides), molecules which when released into the atmosphere react with sunlight and convert to Ozone, an irritant gas that is particularly harmful to people with asthma or cardiovascular illnesses.
Recently, the US set stringent limits on NOx production from cars, and the cities of London and Paris are, for the above reasons, said to be planning to ban diesel cars by 2020.
So why don’t car companies just reduce or filter out these NOx(ious) pollutants? Because simple solutions would require (or result in) a reduction in the engine’s power or fuel efficiency, or both. And that would turn away customers, who don’t want to drive sluggish cars, especially if diesel fuels are not much cheaper than gasoline.
Complex Solutions
More complex (and expensive) solutions exist. Indeed, Mercedes-Benz and BMW have diesel engine systems that take care of the NOx production, for instance by mixing in urea, a liquid whose molecules combine with the nitrogen oxides into products that can easily be removed and not released into the air. Alternatively, some researchers are trying to develop diesel engines that operate at low temperatures, which would then solve all problems at once. But this is quite a challenging problem.
Volkswagen, however, chose the easy way of cheating: pretend the NOx gases are being filtered away, without actually doing it, in order to preserve the vigorous driving styles of its cars.
Diesel engines represent a problem in many places, where exhaust pollution limits are not nearly as stringent as in the US. Indeed, European limits on Ozone, NOx, Sulfur and other pollutants are much more lenient than WHO (World Health Organisation) recommended limits. In many countries, particularly in Asia and Africa, diesel is cheap because it is used by farmers and food transporters.
Raising its price would raise prices for all food and other products; lowering it would make diesel-engine cars very attractive and thus increase the pollution.
The solution may lie in imposing stringent car exhaust emission limits, as the US has done, but this presumes effective monitoring systems. One may impose high taxes on diesel-engine cars, thus making them uneconomical for customers, without raising the price of diesel fuels, which are needed elsewhere in society. And perhaps ideally, both of these solutions should be implemented in tandem.
Volkswagen’s cheating was so shocking because the culprits prioritised company profits at the expense of people’s health and on a huge scale. This reminds us of the utmost necessity to make ethics a central subject of education, at all levels and in all fields.
— The writer is a Professor of Physics and Astronomy at the American University of Sharjah. You can follow him on Twitter at: www.twitter.com/@NidhalGuessoum.