
Independent research in the UK has bolstered BMW's already strengthening green credentials.
The comparative study by cleangreencars.co.uk gives the marque a solid lead over its German counterparts in reducing CO2 emissions.
BMW has recorded the lowest average CO2 output figure among luxury manufacturers for the second year running, with a UK fleet average of 159.4g/km, against a total industry volume average of 156.7g/km for 2008.
BMW has 21 models coming in under 140g/km.
By comparison, Audi averaged out at 173g/km; Mercedes-Benz 189.9g/km; Jaguar 198.3g/km, Land Rover 251g/km and Porsche 271.7g/km.
The study estimates that EfficientDynamics technologies have cut CO2 emissions across the BMW range by around 58,000 tonnes in the UK over the two years since their introduction.
Their arrival has heralded fuel consumption improvements of up 24 per cent and emissions reductions of up to 21 per cent over 2006 models.
EfficientDynamics covers such features as auto start/stop, regenerative braking, active aerodynamics, low rolling resistance tyres, electric power steering, on-demand activation of ancillary systems and optimum gearshift indicators.