28 July/August 2026 | E-Mobility Engineering Tuning efficiency Liebherr only launched the unplugged range of its heavy-duty machinery once it had the knowledge that the available components could be combined to deliver the same performance as the existing diesel-based machinery – but it is the efficiency gains that have proved most impressive. “A diesel unit needs 8 or 9 litres of fuel per hour, which is around 90 MWh, but from our experience with the electric machines, they only need 30–32 MWh,” explains Mewes. “So, thanks to the electric efficiency compared to burning fuel, it only requires one third of the energy that a diesel engine would use – that brings with it significant cost reductions, which is very attractive to a lot of customers. “For the pile driver, the efficiency of the hammer is important, and the transfer of energy into the pile is 95% with the electric motor. I believe a diesel motor has around 50–55% efficiency, but an electric motor has 99% efficiency. We have also seen the benefit in maintenance and servicing of the machines. A diesel-driven engine requires a service every 500 hours, whereas the electric machines stay more or less maintenance-free.” The elimination of the diesel engine, gearbox, oil filters and other ICE-related requirements, and the reduced material stress owing to the smoother electrical operation causing fewer vibrations, add up to a reduction of 40–50% in maintenance costs compared with the diesel engines – and with the electric machine itself costing around 25% more than a regular machine, Mewes says that the lifetime savings make it “absolutely appealing.” The electrification comes with the addition of some complex digital systems and remote monitoring capabilities. The operator controls remain as simple as before, but behind the scenes, the software that the Liebherr Group has developed takes control. “There is a complete control system in there but all the operator sees is a display in the upper carrier or in the cabin,” he says. “It is also possible to download a mobile phone app, so wherever in the world our customers are, the status of the operation and of the battery charging can be seen. The machines also have GPS, so the operator knows exactly where the machines are and the Liebherr computer program ‘My Jobsite’ sends all the data to the customer, providing a full diary of the complete job site. So every pile has its own story!” Core to the operation is the company’s in-house software, which manages all the onboard safety systems, with an insulation monitoring system that continually checks to ensure electric safety and sends the driver a notification for manual shutdown if there is a leakage or any potential faults, and a battery management system, which monitors the key parameters – the voltage, current, charging, deep discharge and balancing of the different cells – and keeps everything in check. “This is all managed from the inside,” adds Mewes. “From outside, nothing is noticeable.” The electric piling rigs are now running throughout Europe – in Austria, Denmark, France, Germany, Great Britain, Netherlands, Norway, Sweden and Switzerland – and also in the USA, Canada, Dubai, Hong Kong and Australia. Given the scale and diversity of operational locations, the team had to robustly engineer the electronics, battery system and drivetrain to be capable of operating reliably in both extreme heat and extreme cold conditions. Key to that was the twincircuit cooling approach that Liebherr has developed in house. “The system has two circuits – one for battery cooling and a second for all the components,” says Mewes. “Without any changes in the design, this allows our machines to run everywhere from the cold Scandinavian Arctic to the hot climate of Dubai. The thermal management system keeps the batteries always at a storage temperature of 15–20 C, so if it’s too hot These giant machines operate on sites where limited movement is required, making their operation the biggest focus in electrification
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