BMW Group Logistik, in collaboration with German e-trailer manufacturer Trailer Dynamics, has conducted tests to compare the performance of an electrically powered semi-trailer combined with a diesel tractor on varying routes in a simulation of real-world logistics operations.
The companies conducted four days of tests over distances of up to 250 kilometers each day on motorways and main roads. Three days of test drives covering the 450 kilometers between Leipzig and Mamming carried loads of more than 17 tons of energy modules for BMW electric cars, mainly on motorways.
According to BMW, the average fuel savings compared to a conventional semi-trailer were more than 46% over short and medium distances and more than 48% over long distances. The combination of electric tractor and e-trailer achieved a range of more than 600 kilometers on a full charge.
The Trailer Dynamics e-trailer has its own battery and electric drive axle, which supports the tractor’s engine. Integrated sensors on the kingpin between tractor and trailer maintain an optimum load ratio to achieve optimum fuel economy. The axle also supplies additional power during start-up and on slopes.
“The fuel savings when using e-trailers are counterbalanced by their heavier weight and the resulting lower payload, but this is partially offset by an increase in the permissible total weight for trailers in the EU. The higher acquisition costs of the e-trailer are counteracted by lower operating costs,” BMW said.