The Department of Transport (DfT) has published its research into emissions levels from diesel cars following a scandal which revealed that several companies had been manipulating emission controls. The DfT report that, for all vehicles which they tested, nitrogen oxide conditions were higher in real world conditions than in laboratory conditions.
Dr Jo Barnes, Research Fellow, Air Quality Management Resource Centre, University of the West of England, said:
“It is fantastic news that the UK government has now finally officially, and independently, acknowledged the extent of the discrepancy between test cycle and real world emissions across all motor manufacturers. At last air quality modellers can now stop labouring under the false pretence that published emission factors are “realistic” and, through the implementation of on-road real-world emission testing, motor manufacturers will now have to ensure new vehicles are cleaner.
“There is still a long way to go however to ensure public health is protected from vehicle emissions. The agreed new emissions tests will still allow emissions to exceed the standards by twice as much and, compared to US standards, it could be argued even the standards themselves are too lenient.
“It is also unclear what the government plans to do about the dirty vehicles that are already on our roads. Will a new scrappage scheme be in order?
“This will also have implications for the new Air Quality Plan that Defra has just submitted to the European Commission. Effectively this announcement undermines the emissions forecasts that underpinned Defra’s assumption that health-based air quality limit values would be achieved by 2020 in most areas and by 2025 in London and would push this date on by years.”
Declared interests
Dr Jo Barnes: “We have recently been funded by Gatwick Airport Ltd to investigate the robustness of the assumptions underpinning Defra’s draft Air Quality Plan.”