Recently Vahle has developed several innovative solutions for the port logistics industry and has become a well-known innovator for environmentally friendly current supply systems for port cranes. As of now, eight diesel generator powered RTG´s (Rubber Tired Gantry Cranes) will be modified so that they can be powered directly by the existing electrical net. RTGs do not run on tracks and can travel in and out of several aisles between the stacked containers. The order comprises three facilities with aisle lengths of 400m, 300m and 80m.
The Vahle developed system functions as follows: when a RTG enters a container aisle the diesel generator is switched off. The RTG is plugged manually into a mobile power unit which moves with the RTG along a current conductor system installed at the side of the container aisles. This modification makes the operation of the RTGs environmentally friendlier, moreover it reduces operating cost by up to 50%. It also substantially reduces the maintenance requirements for the diesel generators and thus downtime for the RTG´s. At Port Mardas, where the RTGs operate approximately 12 hours per days, the savings amount to over Euro 350,000 per annum. In addition, the modified installation operates with a significant noise reduction and reduces CO2  emission.
Vahle not only offers the manual plug-in version, there is also a highly efficient fully automated system with an telescopic connecting arm. Here the manual plug-in procedure is eliminated. The connection to the conductor system is fully automated resulting in extremely short entry and exit times to and from the aisles. Both systems can be used for new installations or to retrofit existing RTGs.