The mobility sector is changing rapidly. While customers' demands for comfort and digital networking are increasing, legislators are calling for a sustainable reduction in CO2 fleet emissions to 95 g/km by 2020. Against this background, 48V technology is an attractive option. As early as 2018, Volkswagen announced at the renowned Vienna Motor Symposium that it would make the innovative low-voltage concept accessible to a broad public. Now the Group is delivering on its promise and bringing it into series production this year – with the eighth generation Golf, one of the best-selling vehicles in the world. Initially, the 48V hybrid drive will be available with the EA211 evo family, 1.0 and 1.5l displacement and dual-clutch gearbox (DSG). Volkswagen will then gradually extend the electrification of the drive system to the entire fleet. But what exactly is behind the technology and what are its greatest strengths?
One hybrid, two engines
Compared to current Plug-in Hybrids (PHEV), for example in the Golf GTE and Passat GTE, the mHEV drive (mild hybrid electric vehicle) equipped with 48V technology offers a reduced range of functions, but is significantly more cost-effective. While the Plug-in Hybrid (PHEV) charges the battery via the mains with a plug, the mHEV does not have a battery that can be recharged via a plug, but is equipped with a 48V belt starter generator. As an electric motor, this supports the combustion engine in order to increase the drive power according to the situation – for example when accelerating. In 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 making major changes. Depending on the driving style, the mHEV system can save about 0.4 liters of fuel per 100 kilometers.