This is how the mHEV system of the new Volkswagen Golf 2020 works

The Volkswagen Golf 2020 will feature a 48 V mild hybrid system that will allow it to comply with the new emissions regulations.

The eighth generation of the Volkswagen Golf will feature a new electrified system. It is a 48-volt mild hybrid system. The brand calls it mHEV, and the Volkswagen Golf 2020 will be the first model from the German manufacturer to be equipped with it.

The mobility sector is changing rapidly. While customers’ demands for comfort and digital connectivity are increasing, lawmakers are calling for a sustainable reduction in CO2 emissions by 2020. In this context, as the German brand asserts, 48-volt technology is an attractive option.

Volkswagen already announced during the Vienna Motor Symposium last year that it would make this innovative low-voltage concept accessible to a wide audience. Now, the group is fulfilling its promise and putting it into series production this year with the launch of the eighth generation of the Volkswagen Golf, which has just turned 45 years old.

The 48-volt mild hybrid version will be available in the EA211 evo engine family, 1.0 and 1.5 litres and with the DSG dual-clutch gearbox. The brand has stated that it will gradually extend the electrification of the transmission system to its entire fleet.

Volkswagen Golf mHEV

If we compare this new mHEV system with the brand’s current PHEV models, the Volkswagen Golf GTE and the Volkswagen Passat GTE, it can be deduced that although it is limited in functions, it is “significantly cheaper”.

The PHEV system charges the battery from the electrical grid via a plug, whereas the mHEV does not have a battery that can be recharged through a plug, but it is equipped with a 48 V starter-generator. As an electric motor, it supports the combustion engine to increase drive power according to the situation. During deceleration phases, the generator converts the vehicle’s kinetic energy and charges the battery with energy that would otherwise be lost.

This combination offers Volkswagen the opportunity to electrify conventional powertrains without major changes.

How does the Volkswagen mHEV system work?

In the mHEV engines that the new Volkswagen Golf will feature, the belt-driven starter-generator and an electric motor with a 48 V voltage act as a powerful replacement for the alternator. When starting, it also increases engine torque through the boost function, “which ensures greater dynamics and comfort”.

The power is transmitted to the crankshaft via the belt drive. In addition to the standard 12 V battery, the mHEV unit has a 48 V lithium-ion battery mounted under the passenger seat. When the driver presses the brake, kinetic energy is converted into electrical current. This makes it possible to recover up to 40% of the braking energy and store it in the battery.