Car makers miss carbon dioxide target by 39%

Real-world emissions testing of passenger cars shows greenhouse gas emissions exceeds the official figures on which UK national objectives and vehicle taxation are based.

The latest component in the EQUA Index series, the new EQUA CO₂ programme, shows the extent to which this is happening.

The new EQUA CO₂ Index rates cars for their absolute level of CO₂ emissions, and how close to their official figures they get.  The prestigious “A1” rating is currently only achieved by one vehicle, a Citroen C3 diesel – “A” representing the best absolute emissions, and “1” the accuracy factor.

Taking the car market as a whole, average real-world emissions of Euro 6 cars are 181 g/km of CO₂ – a figure that hasn’t improved since the previous, Euro 5, generation of car. Compared to the current legal fleet average target of 130 g/km of CO₂, the new EQUA data shows that this legal target is being exceeded by 39 per cent.

Average CO₂ emissions from new gasoline cars have fallen by 6 per cent since 2012, when Emissions Analytics started collecting data. However, over the same period, the average emissions from diesel cars have risen by 5%.  So, even though diesel engines remain lower-emitting than petrol in absolute terms, the gap is closing.

Nick Molden, chief executive officer and founder of Emissions Analytics, said: “In recent years, we have been kidding ourselves about our actual achievement in reducing CO₂ from cars.  Encouraging official data has given a misleadingly positive impression.  The new official world harmonised test will help close the gap, but only partially.”

                                    Free data for 60,000 cars

Complementing the recently-launched EQUA Mpg, which provides real-world fuel economy figures for more than 60,000 cars, the new CO₂ data is derived from the largest independent on-road emissions testing programme in Europe. Delivering impartial and precise information, the results are openly published data.

Detailing the deviation between official and real world, the new EQUA CO₂ Index provides a compelling resource for policymakers on the progress against our climate change goals, vehicle fleet operators assessing environmental impact and the motor industry itself.

Offering a simple scale that denotes each car’s performance, the new EQUA CO₂ Index awards a universal rating regardless of fuel type. Banded from A1 to H5, it provides a simple way to evaluate emissions of this greenhouse gas. “A1” is the best (A) and most accurate (1) while “H5” is the worst (H) and furthest from the official number (5).

Offering a deeper dive into the same information that powers the company’s real-world fuel economy data for cars, the new index provides an invaluable resource for the motor industry, allowing it to track the emissions of the greenhouse gas in relation to other harmful pollutants. The programme joins the growing range of tools from Emissions Analytics, including EQUA Mpg, EQUA Aq, which measures real-world emissions of nitrogen oxides, and EQUA CO, for poisonous carbon monoxide.

Emissions Analytics, based in Stokenchurch, Buckinghamshire, UK, Hamburg, Germany and El Segundo, California, USA, has tested hundreds of cars in standardised, on-road conditions. Its test cycle delivers drastically more realistic figures than the new official fuel economy test, the World harmonised Light vehicle Test Procedure (WLTP), set for introduction in 2017, which will still relies on laboratory-based testing.

                                                 Major obstacle

With carbon dioxide seen as the major obstacle in addressing global warming, it’s estimated that cars are responsible for around 12 per cent of total EU CO₂ emissions. The law requires that new cars registered in the EU emit no more than an average of 130 g/km of CO₂, judged as an average across manufacturers’ fleets_.  By 2021 the average to be achieved falls to 95 g/km.

The data within the new EQUA CO₂ Index also reveals that 1.5-litre engines typically deliver the best real-world CO₂, rather than the most heavily ‘down-sized’ units.  Engines between 2 and 3 litres are typically closest to their official numbers, with around 40 per cent of vehicles achieving the “1” accuracy rating.

The launch of the new EQUA CO₂ Index also adds intelligence to the recent petrol versus diesel debate. The index’s data shows that, when comparing a range of engines in the real world, diesel engines typically generate 169 g/km of CO₂, compared to 196 g/km for petrol units. This equates to a 16% difference in diesels’ favour when comparing like for like. Despite the recent controversy over manipulated NO_x emissions, it underlines the fact that the manufacture of more petrol-powered vehicles, to address environmental concerns, could negatively impact CO₂ pollution levels.

Ensuring that the EQUA Index remains robust and relevant, an advisory board of leading academic and industry experts has been assembled.  The board includes individuals from Imperial College London, King’s College London, the International Council on Clean Transportation and the University of Cambridge. Providing advice and guidance, as well as reviewing the test and rating methodology, the committee will provide input into the wider development of the programme.