Plug-in hybrid cars pollute more than advertised, tests show
BMW, Peugeot and Renault hybrid cars emit significantly more carbon dioxide than advertised, new tests have revealed.
Three recent plug-in hybrid electric vehicles (PHEV) – the BMW 3 Series, Peugeot 308 and Renault Megane – were found to have emitted much more than official ratings when driven “on a typical commuter route”.
The BMW model emitted more than 100 gCO2/km – three times the official rating – tests by Graz University of Technology, commissioned by European clean transport campaign group Transport and Environment, found.
PHEVs bridge the gap between a battery electric car and a conventional car with a petrol or diesel engine.
When tested on a commuter route with a fully charged battery, the Peugeot and the Renault emitted 1.2 to 1.7 times the official CO2 (33 - 50 gCO2/km).
The Peugeot 308 and Renault Megane plug-in hybrids polluted 20 per cent and 70 per cent more than claimed respectively, despite the relatively short round-trip distance covered (55km), Transport and Environment said.
They performed comparatively better than the BMW, which emitted more than three times the official rating.
In city driving, the Peugeot had just 53 per cent of the advertised electric range on a single charge, while the BMW had only 74 per cent.
Only the Renault had the electric range claimed.
PHEVs are sold as the “perfect combination” of a battery and engine, but testing shows this is “a myth”, Transport and Environment vehicle emissions manager Anna Krajinska said.
“In city tests, just one of the PHEVs has the electric range advertised, while all three emit more than claimed in commuter driving. Lawmakers should treat PHEVs based on their actual emissions.
“Private car and company car taxes for PHEVs should be based on the actual CO2 reduction delivered. Governments should end all purchase subsidies for PHEVs in fleets and instead encourage companies to use battery electric cars which are truly zero emissions.”
The tests also showed that the BMW and Peugeot models emitted high levels of CO2 when the battery was not charged. The Renault had lower emissions.
It also found that the electric range of all three models was less than 50km.
BMW achieved a 26 per cent lower electric range and Peugeot 47 per cent lower than expected based on official data. Only Renault achieved the expected electric range.
The Transport and Environment report concluded: “While official CO2 emissions of PHEVs are low, real world data shows that PHEVs are driven electrically less than assumed by regulation. This means that in reality, the official CO2 of the three PHEVs tested should be 85-114 g/km.”
BMW said official emissions data for its cars is measured through the standard WLTP test cycle - an internationally recognised process certified by government authorities - as for all manufacturers.
“On-the-road driving presents infinite variability of multiple criteria and so it is not surprising that there are some differences to the WLTP figures,” a statement said.
Peugeot said its vehicles are fully compliant with all regulations and the conditions of tests that are required.
“The report makes some conclusions based on non-regulated tests and data which lacks further information on the detailed conditions,” the company said in a statement.
“The results depend heavily on driving style, type of route, traffic and even environmental factors, such as temperature and weather. Depending on these factors, the range achieved may increase or decrease, even considerably.”
Renault has been approached for comment.