A battery bank could make a huge difference

The world is moving towards battery-electric vehicles (BEVs) and alternative fuels, with good reason. Engines aren’t the only components that can benefit from electrification, though.

German multinational engineering and technology company Bosch already highlighted the benefits of electrified semitrailers back in 2018. It presented an electrified axle at the IAA commercial vehicle show in Hannover that year, which could be integrated into these truck-towed transporters. The idea behind it was quite simple: integrate an electrical machine into the semitrailer’s axles, instead of simply allowing them to roll freely, as had been the case up to then. That meant they could generate electricity during braking and feed it into the trailer’s power units.

In the case of a refrigerated trailer, Bosch estimated that the saving could be as much as €10,000 a year. Bosch calculated that operating the cooling unit using power generated in this way could save up to 9,000 litres of diesel a year, while an electrical start and acceleration boost function could save additional fuel.

“Bosch is making trucks’ rear axles electric and smart. Our electrification solution for trucks makes economic sense and shows how electromobility can work even in today’s [diesel powered] trucks. Bosch’s electrified axle makes trailers independent. By electrifying trailers, Bosch is taking an important step toward automated parking at freight depots,” said Dr Markus Heyn, member of the Bosch board of management.

“They also facilitate remote-controlled electric driving on private property such as freight companies’ premises or at ports. Up to now, truckers have had to do this task themselves, or a special trailer-shunting unit has done it for them,” he continued.

“Now, however, the electric motor makes the trailer into an independent vehicle that can travel short distances. With the help of additional sensors attached to the trailer and installed at various points in the depot, it will be possible for goods trailers to park themselves.”

Bosch isn’t the only company that is going the electrified semitrailer route. ZF’s latest version of its own concept to electrify trailers was on show at the NUFAM commercial vehicles trade show in Karlsruhe, Germany, in the third quarter of last year. Here, the company announced a cooperation with BPW to offer a fully integrated running gear system for trailer builders, including ZF’s AxTrax 2 electric axle.

“Electrification for trailers is an innovative solution to decarbonise road freight transport in the very near future,” noted Dr Bernd Meurer, who is responsible for the electric trailer programme at ZF. “Instead of solely being pulled by the truck, [this] approach provides additional traction while generating fuel savings, reducing CO₂ emissions and improving sustainability.”

The company highlighted that its AxTrax 2 electric axle, with a modular battery system box for recuperation and traction support, effectively converts an extra-heavy commercial diesel truck into a hybrid vehicle. It can generate up to 16% fuel and CO₂ savings, while the optional plug-in variant saves up to 40%. The trailer also provides benefits for zero-emissions electrified heavy trucks by extending their range.

“The fact that industry leaders are embracing our system demonstrates that we have taken the right concept approach in developing a lightweight and modular system that can be adapted to suit the diverse requirements and various applications of manufacturers and fleet operators,” Meurer added.