The RC HYmotion4 concept is one of several hybrid concepts using a new through-the-road hybrid system being shown in Paris by Peugeot and Citroen. Unlike the hybrid systems used by current production vehicles, this one has no direct mechanical connection between the electric and internal combustion drive systems. The Peugeot RC has a turbocharged 1.6L four-cylinder in the back driving the rear wheels with 218 hp and 206 lb-ft of torque, while additional propulsion comes from a 70 kW electric motor situated between the front wheels. This way, the RC can operate in either rear-, front- or all-wheel-drive modes. That means it can also operate using internal combustion, electric only or blended modes, respectively. The 3,141-lb four-door coupe accelerates from 0-62 mph in just four seconds when both gasoline and electricity are flowing. The electrons are stored in a lithium-ion battery pack of indeterminate size, but having the electric motor at the front instead of the rear axle means that more kinetic energy can be recaptured through regenerative braking. According to Peugeot, the RC can get 52.3 mpg and output CO2 emissions of just 109 g/km. It's a trick system for sure, but there's no word on whether it's ever going to be produced.
http://www.autoblog.com/2008/10/03/paris-2008-peugeot-rc-hymotion4-concept-gets-52-3-mpg/
