Yesterday, DailyTech reported on VW's intention to bring a diesel-electric hybrid Golf to market. The hybrid powertrain would boost fuel economy to nearly 70 MPG on the small two/four-door hatchback.

BMW also has diesel-electric hybrids on the brain with its new Vision EfficientDynamics concept vehicle. The concept is based on the X5 Sports Activity Vehicle (SAV) and uses a 2.0-liter, 4-cylinder Variable Twin Turbo diesel engine. The diesel motor develops 204 HP and 295 lb-ft of torque.

Unlike the previous BMW X6 ActiveHybrid concept vehicle which was a full hybrid, the Vision EfficientDynamics is a mild-hybrid vehicle. A 15kw generator boosts total power to 221 HP, while regenerative braking steps in to help power the vehicle's electrical systems and recharge the rear-mounted lithium-ion battery pack.

Power is routed through a new ZF-manufactured 8-speed automatic transmission which sends power to all four wheels thanks to BMW's xDrive AWD system.

Further electrical power for the vehicle comes from a one square meter solar panel mounted on the roof of the Vision EfficientDynamics concept. The panel can generate one kW hour of energy to help power ventilation systems, audio equipment and facilitate in-vehicle device charging (i.e., iPods, cell phones, etc.).

The advanced powertrain coupled with exterior refinements including aerodynamic spokes on the rims allow the Vision EfficientDynamics concept to achieve 36 MPG combined. The vehicle can accelerate to 60 MPH in 8.9 seconds and towing capacity is a respectable 5,000 pounds.

BMW has a number of diesel vehicles heading to the U.S. in the coming years. Within the next year, the U.S. will see a 335d and an X5 xDrive35d -- both will feature a 3.0-liter Variable Twin Turbo diesel engine which produces 265 HP and a tire-shredding 425 lb-ft of torque.

Hopefully, the four-cylinder diesel-electric mild hybrid powertrain won't be far behind in making its way to future BMW models.