CO2 emissions could rise if buyers shun diesels

Latest industry report says UK could miss environmental goals due to shift away from diesel-engined cars...

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Claire Evans
27 Feb 2018 00:05 | Last updated: 14 Jun 2018 00:03

A new report from the Society of Motor Manufacturers and Traders (SMMT) revealed that average CO2 emissions of newly registered cars rose in 2017 – the first increase in 20 years.

Even though new cars are more environmentally friendly than ever, on average emitting 12.6% less CO2 than the cars they’re replacing, the public’s switch from diesel to petrol upped average emissions last year by 0.8% to 121g/km.

Although that figure is up on 2016, it’s still a third lower than the average emissions in 2000. The growth has been attributed to two things: a decline in demand for new diesel cars and a substantial reduction in the number of small cars being registered.

CO2 emissions could rise if buyers shun diesels

Diesel sales were down by 17% in 2017 and the take-up of hybrids and electric vehicles wasn’t big enough to bridge that gap, with these two types of cars accounting for just 5% and 0.5% respectively of the 2.5 million new cars sold in 2017.

SMMT chief executive Mike Hawes blamed the Government’s anti-diesel agenda for setting back progress on climate change. He said: “The industry shares the Government’s vision of a low-carbon future and is investing to get us there – but we can’t do it overnight, nor can we do it alone.

“Motorists must have the confidence to invest in the cleanest cars for their needs – however they are powered. A consistent approach to incentives and tax, and a greater investment in charging infrastructure, will be critical.”

If this upward emissions trend continues, it will be harder for the UK to meet the European Union’s 2021 CO2 emissions target of 95g/km. The issue is likely to be compounded by the introduction of more realistic fuel economy and emissions testing later this year. The World Light Vehicle Test Procedure (WLTP), which comes into force from September, will provide CO2 and MPG figures that are more closely achievable in real-world driving.

The most fuel-efficient family cars

The fuel economy figures published in sales brochures can tempt you into buying a particular car, but they can be misleading. Fortunately, What Car?'s True MPG tests reveal what sort of fuel economy you can expect in the real world.

To ensure accuracy and repeatability, our tests are conducted under strictly controlled laboratory conditions but based on a real route that takes in urban, A-road and motorway driving.

Below, we take a look at the most efficient family cars we've tested so far.

10. Renault Mégane 1.5 dCi 110

Official combined mpg 72.4 True mpg 47.2 % difference 34.8%

CO2 emissions could rise if buyers shun diesels

Despite having a True MPG score that's almost 35% down on its manufacturer claim, the Mégane is still a very economical family car. Every model gets plenty of standard equipment and this small diesel engine has nice mid-range pace. With low CO2 emissions, it's also the option of choice for company car buyers.

Read our full Renault Mégane review

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9. Audi A3 2.0 TDI S line

Official combined mpg 61.4 True mpg 47.3 % difference 23.0%

CO2 emissions could rise if buyers shun diesels

The A3 is a former What Car? Car of the Year and, in five-door Sportback form, it's still one of our favourite family cars. This 2.0-litre diesel engine is, we think, worth the price premium over the 1.6 diesel and should be on your shopping list if you'll be covering a lot of miles.

Read our full Audi A3 review

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8. Skoda Superb 2.0 TDI 150

Official combined mpg 68.9 True mpg 48.2 % difference 30.0%

CO2 emissions could rise if buyers shun diesels

We're big fans of the current Superb and we named this 2.0 TDI 150 version as the best executive car for less than £25,000 at the most recent What Car? Awards. The Superb offers vast amounts of space inside and is keenly priced, whether you're buying outright or on a PCP deal. It really is one of the best cars around for you and your family.

Read our full Skoda Superb review

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