Tax incentives designed to help promote the adoption of technology that is slightly more expensive but in the end, more fuel efficient, are growing rapidly. The IRS' Lean Burn Technology Motor Vehicle Tax Credit, for example, is targeted at reducing greenhouse gas emissions. BMW announced today that its 335d sedan and X5 xDrive35d SUV both qualify for credits under the measure.

The 335d sedan is eligible for a $900 tax credit under the Lean Burn bill, while the larger X5 xDrive35d can tap up to $1,800 in credit. "Qualification for these tax credits is further recognition of the remarkable efficiency of our new BMW Advanced Diesel models," said Jim O'Donnell, President of BMW of North America.

Qualifying for the Lean Burn credits is impressive considering the 335d's 6 second 0-60mph acceleration time and 265hp/425lb-ft (197kW/575Nm) output. Its fuel efficiency is what gets it the credit, coming in at 23mpg city and 36mpg highway. The X5 is equally remarkable, securing a 19mpg city/26mpg highway rating while maintaining a 6.9 second 0-60mph run.

Other vehicles eligible for similar tax credits include the Volkswagen Jetta and several of Mercedes' BlueTec diesels (both eligible under the Lean Burn program), plus the Ford Fusion Hybrid, eligible under new hybrid incentives.