Industry body blames diesel backlash for first new car CO2 emissions rise in 20 years

New cars on the roads of the UK pumped out more CO2 for the first time since records began, according to figures released today by the Society of Motor Manufacturers and Traders (SMMT).

New cars averaged 121.04g/km, edging up 0.8% on 2016. The SMMT said this is the first year the figure has risen since records began in 1997. The trade group is blaming increases on the backlash against diesel vehicles, which are said to pump out less CO2 than petrol vehicles. 

Figures also hint that confusion over the future of diesel vehicles have driven the first slump in UK sales of new cars since 2011. After five years of strong growth, sales of new cars fell by 5.7% in 2017, mainly due to a massive 17% fall in sales of diesel vehicles. Changes to diesel tax rules and a new government air quality plan are believed to have had an adverse impact on sales with drivers less keen to part with their money when the future for motoring remains unclear.

Mike Hawes, SMMT's chief executive, said: “Diesel cars, due to their greater fuel efficiency, typically emit on average 20% less CO2 than the equivalent performance of a petrol-engined vehicle. It’s disappointing, therefore, to see these advances undermined by the backlash against cleaner, low emission diesels, with the recent drop in sales the prime cause of this increase in CO2 emissions.” 

The SMMT boss has called on the government to “stop the negativity” around diesel and recognise that for motorists doing longer trips, it can be more environmentally friendly than petrol, though acknowledged for short journeys in congestion petrol is better. 

Hawes added: “New technologies, including the latest low emission diesels, are vital if the country and the industry are to meet their climate change targets. For the industry, hitting the 2020/2021 goals will be extremely challenging and government must create the right policies and incentives to encourage all low emission vehicles irrespective of fuel type, whether that means battery vehicles, hybrids, plug-in hybrids, hydrogen or petrol and diesel models.”

While the figures have provided rather bleak viewing for the auto industry, the market for greener cars continues to grow. Electric and hybrid car sales hit a record high in 2017 with almost 120,000 'alternatively fuelled vehicles' on UK roads last year - up 34.8% on 2016.

James Thornton, chief executive of environmental law firm ClientEarth, said awareness of ever-increasing Clean Air Zones around the country meant the decline in diesel cars purchases was inevitable. "It's no surprise that diesel sales were down last year,” he added. "Diesel vehicles are responsible for much of the illegal and harmful levels of air pollution in towns and cities across the UK. Clean Air Zones, which charge the dirtiest vehicles to enter the most polluted areas, are on their way and people are increasingly aware of that."

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