BMW could bring a clean diesel version of the X1, its new compact crossover vehicle, to the US by 2011. The vehicle will go on sale in Europe this fall, where it will be offered as four separate models—three with a diesel system and one powered by gasoline.

“We’re hoping that by 2011, overall diesel sales will have ramped up in the US,” a source at BMW, who asked not to be named, told “If America starts to embrace diesel, it will allow us to market this vehicle with more confidence.” Unfortunately, BMW apparently does not expect a quick change of public sentiment regarding diesel. USA Today reports that BMW executives have been disappointed with sales of clean diesel vehicles to date. The persistent hurdles for diesel have been the higher cost—both for fuel and the vehicles—and a nagging public perception that diesel fuel is dirty, expensive, and hard to find.

BMW and fellow German carmakers, including Audi, Mercedes and Volkswagen, are pushing forward into the US diesel market. Yet, all six of the main US car sellers—General Motors, Ford, Chrysler, Toyota, Honda and Nissan—have dropped or delayed plans to introduce diesel cars into the North American market.

BMW currently offers two 50-state clean diesel vehicles—the BMW 335d sedan and BMW X5 xDrive35d SUV, carrying hefty price tags of $44,725 and $52,025 respectively. The 335d, which provides a city/highway average fuel economy rating of 29 mpg, is eligible for an “alternative vehicle” credit of $900. The X5 xDrive35d, with an average rating of 23 mpg, qualifies for a $1,550 tax credit.

Pricing for the BMW X1 has not yet been announced.

Ground-Breaking Mileage, If BMW Goes Forward

The X1, a small five-passenger premium utility, is expected to offer fuel efficiency approaching 43 miles per gallon. The clean diesel X1 would become the only vehicle in either the luxury class or the small SUV segment to offer more than 40 miles to the gallon in the United States.

Although BMW has kept much of the technical details under wraps, the carmaker revealed that the X1 comes under the company’s “Efficient Dynamics” initiative. This means it could feature mild hybrid features, such as stop-start and regenerative braking, as well as lightweight steel chassis components designed to maximize efficiency.

The X1 will utilize Dynamic Stability Control and will come in both rear- and four-wheel drive configurations. Safety features include six airbags and active head restraints. Cargo versatility will be provided by a 40/20/40 split rear seat.

If the X1 does manage to get to American shores, it will most likely be eligible for a federal tax credit as an “alternative” vehicle.