The Combustion Engine is Switched off Almost a Third of the Time
In the "Eco Drive" system from Continental, the 48-volt on-board power supply - which supplements the 12-volt supply - consists of three components: an electric motor with integrated inverter which replaces the generator, a 48-volt lithium ion battery, and a voltage converter (DC/DC converter) for exchanging energy between the two on-board power supplies.

The ‘48-Volt Eco Drive' provides significantly more effective recuperation than 12-volt systems. The recuperated energy is stored in the powerful Li-ion battery, so there is more power available for fuel-saving features. This includes extending the start-stop functionality to the driving mode - which means the combustion engine is switched off almost a third of the time.

The 48-volt supply supports the 12-volt on-board power supply and ensures that all the electric features are maintained. In contrast, conventional 12-volt start-stop systems often have to restart the engine in order to operate energy-intensive consumers (e.g. air-conditioning unit) or do not switch the engine off at all when the vehicle is at a standstill.

The ‘48-Volt Eco Drive' switches the combustion engine off as soon as the driver takes his or her foot off the accelerator pedal. This disengages the powertrain from the engine so that the vehicle rolls freely. During an average trip, the system is in ‘coasting' mode around 20 to 25 percent of the time, which alone saves up to 8 percent of fuel.

Furthermore, ‘Eco Drive' has two features by which the electric motor functions as an engine. In ‘sailing' mode - with the combustion engine switched off as in ‘coasting' mode - the electric motor keeps the speed of the vehicle constant for a short period of time. And with the ‘e-boosting' feature, the electric motor assists the engine during acceleration.
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