But you won't know unless you try.
Ferrari and Porsche are doing something like that, with the new Ferrari HY-KER and Porsche 918 Spyder hybrids. Whether or not these plug-in prototypes make it to the sale lot is unknown, but the two models were unveiled today at the 2010 Geneva Motor Show, along with about 60 other alternative-energy vehicles.
Porsche boasts the 918 Spyder, with its 3.4-liter V8 and three electric motors, can reach 78 miles per gallon.
The company explains how it works under the hood:
The energy reservoir is a fluid-cooled lithium-ion battery positioned behind the passenger cell. The big advantage of a plug-in hybrid is that the battery can be charged on the regular electrical network. A further point is that the car's kinetic energy is converted into electrical energy fed into the battery when applying the brakes, thus providing additional energy for fast and dynamic acceleration.
A button on the steering wheel allows the driver to choose among four different running modes: The E-Drive mode is for running the car under electric power alone, with a range of up to 25 km or 16 miles. In the Hybrid mode the 918 Spyder uses both the electric motors and the combustion engine as a function of driving conditions and requirements, offering a range from particularly fuel-efficient all the way to extra-powerful.
Here's a video from the showfloor by our siblings at CNET UK:
Meanwhile, the Ferrari hybrid -- based on the 599 GTB Fiorano -- is green in color, but that's about all.
Mike Chino of Inhabitat summarizes:
When all's said and done, the retrofit is able to boost the vehicle's city mileage by about 50%, although sadly that’s not saying much – we're talking an increase from 9 mpg to 14 mpg.
Nevertheless, there's some interesting tech under the car's hood.
Weighing about 40 kg, the compact, tri-phase, high-voltage electric motor of the HY-KERS is coupled to the rear of the dual-clutch 7-speed F1 transmission. It operates through one of the transmission's two clutches and engages one of the two gearbox primary shafts. Thus power is coupled seamlessly and instantaneously between the electric motor and the V12. The electric motor produces more than 100 hp as Ferrari’s goal was to offset every kilogram increase in weight by a gain of at least one hp.
Under braking the electric drive unit acts as a generator, using the kinetic energy from the negative torque generated to recharge the batteries. This phase is controlled by a dedicated electronics module which was developed applying experience gained in F1 and, as well as managing the power supply and recharging the batteries, the module also powers the engine’s ancillaries (power steering, power-assisted brakes, air conditioning, on-board systems) via a generator mounted on the V12 engine when running 100 per cent under electric drive. It also incorporates the hybrid system’s cooling pump.
Practicality has never been the sports car's strong suit, but maybe something will come from these automakers showing up on the starting line.