Date: 19 May 2017, Science, Technology and Culture
Question setter: Mettletest Panel

UK diesel car sales

Will the UK market share of diesel cars fall below 40% of new registrations for May 2017 (as calculated by the SMMT)?


Answer: No
Confidence level: 65%
Mean confidence level (all requests): 42.17%

There was quite a fall in the market share of diesels between this year and last. This is unlikely to continue until the supply of Alternative Fuel Vehicles (AFVs) becomes sizable and more varied. In particular the demand for larger, high mileage diesels with good economy and Euro 6 compliant emissions should remain firm.
Pressure on diesels is taking three forms. The expense of producing low emission diesel vehicles, the speed of development in AFVs and regulation from central and local government. If you then look at the changing social attitudes to fouling one's own immediate environment, diesel sales are bound to be hit over the next few years. It just will not collapse quite yet and the 40% share level may not be breached for over a year. There is still a strong bias from manufacturers and dealers to sell the current supplies, especially those prepared for the Euro 6 levels. At the moment low CO2 emitting diesels are seen as part of the solution to meet CO2 targets, without regard to NOx and particulate dangers. As electric vehicles appear and charging points proliferate, the incentives will change very quickly. This May is too early for that to translate into sub 40% market share.

Outcome: No
Score: 65
Mean score (all respondents): 13.50

Expert opinion:

Answer: No

Selected Expert Answer from Mettletest Panel:
There has been a flood of official pronouncements and environmental concern on the use of diesel cars in recent months. The Volkswagen emissions scandal and evidence on the dire levels of particulates and NOx in UK cities have sounded alarms. The London Mayor plans penalties and the Lib Dem manifesto demands a ban. They signal new attitudes about the social acceptability of diesel use.
So, two factors are driving a fall in market share from 47.6% down to 44.1% on comparative figures for the first four months of the year - anxiety about causing pollution and the affect on wallets. The combination of wanting to cease poisoning our children and reduced financial advantages could see a very big change in consumer preference quite quickly. Diesel owners fear heavy depreciation on their disdained vehicles, with the tax advantages removed and penalties imposed.
It is not likely market share will go below 40% yet, though. The opportunity is lacking. Electric cars are few, expensive and limited in variation. Diesel cars are still widely recommended by automotive journalists in comparative tests. Dealers and manufacturers continue to offer diesels, expecting tougher regulation (Euro 6) and testing to restore confidence as emissions reduce. The trade predicts a rise in market share for 2018.

Answer: No

Selected Expert Answer from John Karslake:
The move against diesel cars will gain momentum but not fast enough for market share to collapse immediately. The supply of alternative green cars is too small, the dealers have diesel stock and official attitudes are ambivalent because efficient diesels emit less CO2 than petrol equivalents. As CO2 targets are a priority, the Government is loath to penalise too harshly and continues to allow NOx and particulate pollution. New emission standards have seen technology reduce these toxins in new vehicles. If greater cleanliness is proven when on road tests are introduced later in 2017, it might even renew demand briefly.
The collective mind set has been altered long term. We have seen climate change worries subsumed by the more immediate threat of health effects on ourselves and our loved ones. The moment it becomes easy to do so, the majority will switch to alternative fuel cars and driving diesel will be the equivalent of smoking in the baby's nursery.
This month diesel market share will hover above 40% Dealers think it will see a resurgence in 2018. Even if right, an accelerating decline will follow. Professor Seba could be accurate in his prediction that all cars will be electric by 2025.
Penalties for diesel cars, changes in tax and environmental conscience will set the direction.

Outcome: No

Comment on outcome from Mettletest Panellist:
New diesel car registrations continued to lose market share but only down to 43.7% in May 2017. Dealers still have stocks to shift based on historic demand and the promise of lower emissions as cars have to comply with standards in real driving conditions. Yet, research has shown diesel cars are producing 50% more toxic emissions than they should be if they were complying with pollution laws. I would predict that we are going to see a huge reduction in diesel market share over the next decade. The recent cheating scandals and public health concerns have highlighted the damage and driving diesel will become as socially unacceptable as smoking round a baby's cot. As alternative fuel vehicles become more affordable with better range, new owners will increasingly move over.