Bentley is pinning its green future on more efficient gasoline engines powered by biofuel combined with lighter-weight body construction, rather than a radical switch to diesel or hybrid powertrains.
“We don’t think our customers, particularly in North America and Europe, are ready for a diesel Bentley, said Uli Eichhorn, Bentley chief engineer, on Tuesday at the Geneva motor show.
Although Bentley Chairman Franz-Josef Paefgen refuses to rule out a diesel powertrain, Eichhorn said: “Not ruling it out does not mean it is our top priority.”
Hybrid powertrains don’t fit the typical usage cycle of a Bentley, according to Eichhorn. “(Hybrids) are very good in cities and stop-start driving, but that’s not where out cars are used.”
At the Geneva show, Bentley announced a plan to move toward a fleet average of 120g/km on a “well-to-wheel” basis by 2012. Bentley’s fleet currently averages 450g/km on a well-to-wheel basis.
“This is a major step in the history of Bentley,” Paefgen said, “reflecting the increasing expectation from our customers around the world for performance motoring with fuel efficient engines.”
New engine management systems and improved transmissions will cut around 15 percent from tailpipe emissions, which currently average 400g/km across the range.
Bentley said it would introduce a new powertrain by 2012 that will deliver a further 40 percent reduction in fuel consumption. The powertrain will take tailpipe emissions down to 260 g/km.
Details of the new powertrain weren’t revealed, but it is widely interpreted to mean a mild hybrid using stop-start technology and de-clutching alternator, running on second-generation biofuel.
Bentley expects second-generation biofuels to be widely available around the world by then. Gen 2 biofuels are crated from waste material and don’t compete with production of food crops.
Source: AutoWeek by Julian Rendell