Powering ahead to the very last mile: optimising routes for commercial electric vehicles

The battery is almost flat, but the day’s journey is far from over – this kind of scenario surely has every dispatcher breaking out into a sweat. Various surveys show that due to a lack of practical experience, route planning for electric-mobility vehicles in the transport industry has until now frequently involved high safety reserves. Fleet tests in the previous ELMO research project from Fraunhofer Institute for Material Flow and Logistics (IML) show, for instance, that unnecessarily high range buffers are being factored in. Accordingly, available battery capacity is only fully exploited on around 70 to 80 per cent of routes.

Furthermore, as of yet, there is almost no practical experience for commercial electric heavy goods vehicles in actual use. Even current standard planning tools for logistics companies are almost no use, as they are poorly equipped to consider sources of energy consumption such as heating, air conditioning or lever systems and fluctuating loads when calculating energy consumption. ‘At the moment, a lot of it is about trial and error, as there are no sound scientific investigations into optimised route planning,’ explains engineer Arnd Bernsmann from the Transport Logistics department at Fraunhofer IML.

However, in the worst-case scenario, overly cautious route planning can see the environmental and economic benefits of electrification go to waste. With a higher battery capacity, vehicle costs increase dramatically and load capacity decreases. This makes it all the more important to calculate the right battery for your requirements at the planning stage. Otherwise, it’s practically impossible to reach targets for return on investment. ‘In diesel vehicles, it essentially doesn’t matter whether you install a 700-litre or 1,000-litre tank. However, in a commercial electric vehicle, the battery and its costs have huge impact,’ says Bernsmann. ‘If you make a mistake in planning, you risk making a bad investment from the very start – this is a huge challenge for fleet operators.’

This unsatisfactory situation is set to change, however, thanks to EN-WIN (‘Elektromobile Nutzfahrzeuge wirtschaftlich und nachhaltig einsetzen’, or ‘Economic and sustainable use of commercial electric vehicles’ in English), a research project funded by the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU). Researchers at Fraunhofer IML, Fulda University of Applied Sciences and the department of Naturalistic Driving Observation for Energetic Optimisation and Accident Avoidance at TU Berlin are creating the basis for this with a never-before-seen amount of practical data for a wide range of commercial vehicle classes, ranging from five to 40 tons.

They compare data from electric vehicles to that of comparable diesel models as a benchmark. The relevant vehicles are supplied by industry partners Meyer Logistik, Florida-Eis and BPW Bergische Achsen. The range is being expanded in early 2020 to include a vehicle from the 26-ton weight class. The vehicle data in this weight class is being recorded with assistance from haulier companies Geis, Bächle, Max Müller and Logistik in XXL.

First and foremost, relevant factors such as route elevation, weather, changing temperatures, as well as the driver and their driving behaviour, should be taken into consideration. But which parameters have which specific impact on battery range? This question is a key aspect of the research project. Answers should be ready by 2020. In the grocery and distribution logistics sectors, EN-WIN is producing a broad base of data that should enable a profound target–actual analysis for the very first time.

It will take another few months for the data to be analysed and processed. But there’s one thing researchers can already say for sure: in future, new principles will form the basis of route planning. The priority won’t necessarily be the shortest route. It may make more economic sense to visit the customer with the heaviest freight first, to offload weight from the vehicle as quickly as possible – and get battery range into the right region.

Load weight, which doesn’t play a key role for diesel vehicles, has a much heavier impact – in the truest sense of the word – on electric vehicles. ‘Our tests boil down to specific comparisons: how can you design routes with the lowest-possible battery consumption? Do detours pay off and, if so, from which point onwards?’ explains qualified logistics specialist Daniela Kirsch from Fraunhofer IML. ‘It will be a while before systems for future route planning and a new approach from dispatchers have come into play.’

Data from partners’ diesel vehicles has been analysed since the process began in 2017. Specific tests involving electric vehicles have been ongoing since 2018. BPW has been involved since summer 2019. In autumn 2019, industry partner Florida Eis will bring another e-vehicle on board, and its data will also be collected. ‘The entire data collection process has expanded, so the project was extended until the end of 2020 – without any extra cost – to produce sound results,’ explains Bernsmann.

The industry partners have proved to be perfect for Fraunhofer IML: Meyer Logistik and Florida Eis happen to be among the leading users of commercial electric vehicles in everyday transport operations. The ice cream manufacturer, for example, has set itself the goal of climate-neutral manufacturing and transport of its food products. They even dispense with actively chilling the ice cream in the vehicle. Instead, an eutectic system is used, whereby pre-cooled plates keep the load in the defined temperature range. BPW can also draw practical experience from the project results to develop its own electric drive solutions and components. A constant exchange is assured.

Although the mountain of data is set to get even bigger, the researchers are optimistic that they will be able to present the first concrete results in early 2020. Conclusions can be expected on aspects such as which factors (load, weather, route profile, driving behaviour, etc.) have which impact on battery range, and how that impact relates to vehicle size in each case. The ultimate aim is for the project to result in a prototype for a tool that deals with route planning and electric energy simulation. ‘Dispatchers need help planning the use of commercial electric vehicles more efficiently. In future, we will also need networked solutions that can be directly integrated into transport companies’ existing software systems,’ Bernsmann believes.

The researchers already have one piece of good news: the switch to an electrified drive should run smoothly from the driver’s perspective. Practical experience gathered thus far is confirmation of this, says Bernsmann. ‘The drivers are fully on board with the vehicles’ quiet running, powerful acceleration and high level of driving comfort. There is immediate acceptance of electric mobility in commercial vehicles.’