Manchester team investigating pollution before VW scandal

In recent weeks, reports of Volkswagen fitting illegal fuel emission recording devices to cars have been all over the news. However even before the scandal hit, a team of researchers from the University of Manchester were on the case, with research beginning to show just how polluting diesel engines can be.

2001 saw the introduction of a pollution tax on cars—the higher the car’s carbon dioxide emissions, the higher the tax. In order to implement this tax, cars must undergo official testing to determine their emissions.

Typically, diesel cars are marketed as a greener option, and so following the new tax many switched their car from petrol following the new tax; around half of all new cars bought in the UK are diesel. However, the recent VW scandal has uncovered the fact that many drivers who had switched are actually driving cars emitting much higher levels of pollution than advertised, despite believing they were saving money and being more green.

Volkswagen has been found to be using sophisticated algorithms in their emissions recording devices on certain vehicles, which can detect when the car is undergoing official testing. The algorithms ensured that emission controls are only turned on fully during the test in a lab or testing station, therefore meeting the emissions standard required. However, during normal operation the cars have been found to emit nitrogen oxides at up to 40 times the standard that is allowed.

Since the news broke, VW has admitted to 11 million of its diesel vehicles being fitted with the false emission devices, with nearly 1.2 million in the UK affected. The discovery of this scandal will likely have widespread consequences; Volkswagen shares have already fallen 40 per cent since the scandal hit. The company may also face fines of up to $37,500 per vehicle—totalling $18bn altogether.

Investigating the pollution emitted from these diesel engines is a team at the university, led by Dr. Rami Alfarra. The team have collaborated with atmospheric chemistry researchers at York University to test a diesel Volkswagen engine. They aim to piece together an accurate picture of just how polluting the Volkswagen engine is, especially once the pollutants reach the atmosphere.

Their work is conducted using a specially made atmospheric chamber, which can accurately mimic external conditions. This allows the team to monitor precisely the exact emissions produced by the engine and how the particles react with sunlight to create secondary pollution, which has been found to be harmful to human health.

Dr. Alfarra’s team has so far found that nitrogen oxides and particulates were being emitted at elevated levels. However, this was discovered under conditions that are currently not represented in the testing protocols agencies use now, highlighting a possible flaw in the current method.

Despite being the only researchers in the UK looking at this aspect of engines, Dr Alfarra said, “hopefully our work will inform and make engines cleaner in the future.”