Plug-in hybrid cars burn more fuel than tests record, says Which?
Research suggests pollution from the vehicles could be worse than advertised
Plug-in hybrids combine an internal combustion engine with an externally rechargeable battery, in the hope of lowering CO2 emissions while giving the range and refuelling ease of fossil fuels. Photograph: V Kalyniuk/Alamy
Plug-in hybrid cars burn significantly more fuel than official tests record, according to research that suggests pollution from the vehicles could be much worse than advertised.
Tests of plug-in hybrid electric vehicles (PHEVs) by Which?, the UK consumer group, found that some popular cars achieved as little as a third of the fuel economy advertised in official tests.
Cars produced by BMW, Mercedes-Benz, Mitsubishi, Volkswagen and Volvo were among 22 tested that on average burned 61% more fuel than in official tests.
The worst performer was BMW’s X5 plug-in hybrid SUV. It achieved 188.3 miles per gallon in official tests, versus only 52.8 miles for Which?. That 72% efficiency difference could potentially add more than £650 a year in petrol costs, the group said.
The extra fuel burned would result in higher carbon dioxide emissions, as well as increasing running costs for owners. The average extra cost was £462, Which? estimated.
