Based on more than 400 real-world CO2 tests that T&E and FNE performed with Peugeot-Citroën, the briefing, Designing representative vehicle tests: Lessons for EU regulations, identifies three key lessons. Firstly, road tests conducted under controlled conditions are reproducible within a 5% deviation. T&E said this shows that while a road test is not as reproducible as a laboratory test, it does provide a robust basis for estimating real-world emissions.

Secondly, databases of real-world fuel use and other real-world tests are a good basis for deriving real-world fuel efficiency. Meanwhile, the new WLTP test – which replaced the obsolete NEDC test – underestimates emissions.

Thirdly, the driving style in the Real-world Driving Emissions (RDE) test protocol as agreed by the EU is excessively passive and the share of urban driving is seriously under-estimated. T&E said the rules need to be revised.

T&E has been lobbying the European Commission to introduce a real-world CO2 test and a not-to-exceed limit as part of the forthcoming car CO2 regulation. The aim is to stop carmakers cheating the new WLTP test and fit technology that delivers emissions reductions on the road.

The Get Real campaign has already convinced an independent scientific committee of the Commission to recommend the approach. T&E’s clean vehicles director, Greg Archer, said: ‘Cheating carmakers cannot be allowed to circumvent regulations and deceive drivers any longer. If the Commission fails to close loopholes it will be shameless.’