In road testing a hydraulic hybrid truck in suburban Detroit, Michigan, the EPA found the vehicle used 40 to 50 percent less fuel than conventional diesel trucks while reducing carbon emissions by one third.

CNN: EPA, UPS join to launch eco-friendly hybrid trucks

Meanwhile, the UPS hydraulic hybrid transmission truck begins real-world testing on the streets of Detroit later this summer.

NPR: UPS to Test Hybrid Vehicle in Detroit

The electric driving range of the Panamera S E-Hybrid is estimated to be greater than 20 miles based upon current NEDC testing.

ENGADGET: Porsche Panamera S E-Hybrid plug-in model brings 416 guilt-free horsepower