twinDrive
Mobility from the power socket
The Golf twinDRIVE silently glides into the garage. The driver gets out, inserts the plug in the power socket and the battery recharges. This kind of plug-in hybrid gets its charging energy from a socket and from the combustion engine. And the benefits don’t stop there: once technical developments are sufficiently advanced and an adequate number of plug-in hybrids are connected to the grid, these vehicle batteries could even be used as buffer storage to stabilize the power supply grids.
Experts agree there is still a very long way to go before we enter an automobile era that is as clean and resource efficient as this. That applies both with regard to vehicle development and in terms of power generation. From an environmental point of view, electro-mobility is especially meaningful if the electricity is generated from renewable sources.
Twin strengths
The plug-in hybrid system in the Golf twinDRIVE is an important step on the road towards establishing and expanding electro-mobility. The first prototype with its highly efficient diesel engine is fully suited to traveling long distances, but can also cover a range of up to 50 kilometers in pure electric mode. The rear wheels of the prototype are fitted with two wheel hub motors, a compact combustion engine and a further electric motor are installed under the hood, there is plenty of electronic gear and the lithium ion battery is installed in the trunk.
The technology of the Golf twinDRIVE allows the driver to decide on a pure electric mode or the hybrid mode at the touch of a button. Alternatively, the driver can leave this decision to the vehicle. When the destination is entered in the navigation system, the car’s electronic brain computes the most efficient way of using the electric energy stored in the battery until the next “refueling”.
It’s all about the electric motor
In future, urban travel will account for 80 percent of all journeys, so the focus is on efficient and clean drivetrains for short distances. Thanks to plug-in hybrid technology, these journeys can be made in pure electric mode. That is why, unlike hybrid vehicles, the electric motor plays the main role in the Golf twinDRIVE. However, this is only possible if there is an adequate network of recharging points. A fleet test being carried out in Berlin is looking into the kind of infrastructure that is needed as well as the requirements for plug-in hybrids and how they can be further improved. As many as 20 Golf Variant are to be powered by a central electric motor installed on the front axle combined with a gasoline engine.
Apart from several research institutes, an energy supplier and Volkswagen, battery manufacturers are also involved in the fleet test: one of the objectives of the project is to make headway in developing compact high-performance batteries to series maturity.