The ongoing impact of the Volkswagen emissions scandal has seen a 17% drop in new diesel car sales in Ireland in 2017, while the UK recorded a similar slump. And with governments and local authorities starting to introduce legislation and restrictions aimed at removing diesel cars from our roads, that trend is only likely to continue.
That might be good news for reducing harmful NOX emissions and diesel particulates, but remember why there was a wholesale switch from petrol to diesel back in 2008 in the first place. That was because of a change in our motor taxation structure in a bid to reduce CO2 emissions. While diesels may release greater amounts of NOX and particulates, they generally have lower CO2 emissions than their petrol equivalents
But with an increasing number of us reverting to petrol cars, are we in danger of once again increasing greenhouse gas emissions? A report from the UK by Buyacar.co.uk, an online car retailer suggests so. It has revealed Department for Transport figures which show that the average new car sold in 2017 produces more CO2 than one sold in 2016.
That’s reversing a continuous decline in emissions of the greenhouse gas since the figures were first published by the UK government in 2003.
The rise has been attributed by industry figures to the slump in sales of diesel cars which are generally more efficient, and produce less CO2, than an equivalent petrol model.
The information, based on data on new car registrations collected by the Driver and Vehicle Licensing Agency (DVLA) for the first ten months of 2017 show that the average new car produces 121.1g of CO2 per kilometre. The full annual figure is on course to exceed the 120.3g/km recorded last year. It ends a 14 year trend of falling CO2 emissions, which have declined by 4.02g/km annually since 2003.
Any rise threatens to derail ambitious climate change targets. Car manufacturers are under pressure to meet an EU target of cutting average car CO2 emissions across the industry to 95g/km by 2021, but the recent backlash against diesel has shattered their strategy of meeting the target by selling more efficient diesel cars.
Hybrids and electric cars may be the obvious solutions, but while sales of new hybrid cars have increased by over 72% in Ireland this year, and sales of electric cars by over 58%, the numbers remain relatively small at 3.38% and 0.47% of the overall market respectively. It’s a similar picture in the UK.
“Many customers now tell us that they’re avoiding diesel even if it means spending more on fuel” says Austin Collins, managing director of BuyaCar.co.uk.
“Although switching to petrol makes good financial sense for some – especially with plenty of economical petrol, hybrid or electric cars available – diesel’s fuel economy still makes it a good option for long-distance drivers or SUV buyers at the moment.”
Despite all the bad press about diesel, some industry experts say that modern Euro 6+ diesels can actually out-perform their petrol equivalents for CO2 emissions as well as offering substantially lower NOX and particulate outputs.
“If industry is to meet challenging CO2 targets getting more of the latest low emission diesels onto our roads is crucial, as they can emit 20% less CO2 than the equivalent petrol models,” says Tamzen Isacsson, director of the Society of Motor Manufacturers and Traders, the UK industry body. She blames “confusion around government air quality plans and taxation” for the drop in diesel sales, and warned: ”If new diesel car registrations continue on this negative trend, UK average new car CO2 levels could indeed rise this year”.
However the International Council on Clean Transportation (ICCT), a research group that has led the campaign against harmful diesel emissions, said that advanced petrol engines, as well as electric and hybrid technology could cut CO2 emissions without the need for diesel.
“Quite a lot of petrol vehicles do not use the latest technologies available and still have higher CO2 emissions than comparable diesel cars,” said Peter Mock, managing director of ICCT Europe. “However, the – unfortunately often repeated – statement that diesel cars are necessary to decrease CO2 emissions is simply wrong. Instead, hybridizing petrol vehicles and transitioning to electric vehicles today makes more sense for vehicle manufacturers.”
Monk also said that the increasing popularity of tall and heavy sport utility vehicles (SUVs), which are generally less fuel efficient than hatchbacks, had made a significant contribution to the rise in average CO2 emissions.