New figures released today by the Society of Motor Manufacturers and Traders (SMMT) show that carbon tailpipe emissions from new cars have risen for the first time since 1997, with new cars averaging 121.04g/km in 2017, up 0.8% on 2016. 

Confusion over the cleanliness and tax position of diesel cars – and a big fall in their sales – is behind the increase. Diesel cars are relatively efficient in net CO2 terms, but sales continue to be adversely impacted by negative publicity over toxic emissions such as NOx and uncertainty over future regulatory and tax regimes.

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Mike Hawes, SMMT Chief Executive, said: "Industry has spent billions of pounds worth of investment in advanced engine, fuel and battery technologies to help drive down CO2 emissions. Customers reap the benefits of this investment in much improved fuel economy and hence lower bills compared with older models.

"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.

"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. Fleet renewal is the fastest way to lower our carbon emissions and improve air quality and consumers should buy the right car for their driving needs."

SMMT will publish its full comprehensive report on new car CO2 in March.

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