Volkswagen might have been late to the game with the hybrid and electric vehicles while it was busy marketing its efficient diesel engines, but the German giant is certainly trying to make up for lost time. It just unveiled the hyper-efficient, 261-mpg XL1 and is now reportedly preparing a version of its upcoming Up minicar capable of achieving 79 mpg with a similar powertrain.
According to Autocar, the production specs for what will be named the Up Blue-e-motion are identical to those of the XL1 concept: a two-cylinder turbo-diesel displaces 0.8-liters and puts out 47 horsepower and 86 pound-feet of torque and is coupled to a 19-kilowatt (26 horsepower) electric motor and seven-speed, dual-clutch transmission. A key difference between the Up and the XL1, though, is the battery pack. The XL1 operates as a plug-in hybrid, with a battery pack large enough to allow it to run purely on electricity for up to 22 miles. The Up Blue-e-motion on the other hand, cannot be propelled purely on electricity, as the battery pack is only large enough to power the electric motor in assisting the diesel engine. The electric motor will also help reclaim energy normally lost to heat under braking. As the car is production bound, NVH from the inherently unbalanced two-cylinder becomes an issue, and to help remedy that, insiders report that VW has gone to great lengths developing a sophisticated balancer shaft to minimize those vibrations.
Another neat feature VW insiders say the motor will incorporate is a start-stop system with the so called pulse start. Rather than acting as a starter motor to turn the engine over and get it to fire, the electric motor is used to wind the engine up to operating speed before firing. This makes engine restart much smoother and according to the VW insider, and virtually undetectable to the driver.
VW debuted a concept similar to this at the 2009 Los Angeles Auto Show dubbed the Up! Lite concept. That concept used a two-cylinder, turbo-diesel hybrid setup as well and this news about the production powertrain lends credence to the reports that we’ll see a finalized car at the Frankfurt Motor Show later this year. Reports also indicate though, that we’ll have to wait until 2013 for the car to go into series production.