The commitment of municipal utilities to the expansion of electromobility is generally increasing, but varies greatly depending on the institution. Today: a showcase example from the Hessian spa town of Bad Nauheim. The municipal utility there created a pilot charging solution with dynamic load management for a car dealership without further ado.
The distance between the Marnet dealership and Stadtwerke Bad Nauheim is less than four kilometres as the crow flies. In recent months, there has been a lively exchange between the two institutions. The local utility implemented a charging solution with five charging points and controllable load management for the Volkswagen dealership. The starting point for the construction project were specifications from the VW Group that the local branch of the Marnet dealership had to implement. At their heart: four AC charging points with 22 kW and one DC charging point with 24 kW.
At first glance, the necessary expansion of the network connection by setting up its own transformer station would have cost the car dealership a six-figure sum in euros. Together with the municipal utilities, the branch therefore decided to take an innovative approach and set up a pilot project for the integration of dynamic load management. Something that the municipal utilities in the Hessian spa town had not done before. "We then went in search of a partner with whom we could cooperate to implement the requirements in software technology," describes Klaus Tripke, sales manager and fleet manager at the Bad Nauheim municipal utilities. He is not allowed to mention the name of the software specialist, but Tripke speaks of an intensive partnership. Both sides contributed their strengths and thus developed the solution after intensive discussions.
At the heart of the load management system is a control device that ensures that electric vehicles are only charged at the five new charging points on the company premises when sufficient power is available via the house connection. The power demand of the car dealership fluctuates both during the course of the day and seasonally. If vehicles were also charged at all stations at the same time when there was a high general power demand, there would not be sufficient power available," says Tripke. However, to throttle the charging power of the electric vehicles across the board would unnecessarily extend the charging time. Instead, the intelligent system allocates as much power to the charging columns as is currently available. The house connection power is measured at intervals of one second.
The control system also theoretically allows for further leeway: "It can be adapted so that electricity from photovoltaic systems can be optimally used, or it controls the power so that individual charging points are prioritized. This can be individually defined," Tripke informs us. In addition, the management of the charging points is modular. "There are hardly any limits on the part of the software for mapping charging points via the system." Charging parks could thus be created not only at company or hotel parking lots, but also in front of apartment buildings or in underground garages.
From the dealership's perspective, the concept has many advantages: firstly, the branch meets the Volkswagen Group's specifications at comparatively low cost, and secondly, it can show fleet customers in particular what intelligent charging management looks like in practice right on the spot. Specifically, the branch has one charging point installed in the workshop, one in the dialogue reception area and another in the delivery hall. All three offer 22 kW. The hardware comes from wallbe and Schneider Electric. In addition, there are two 22 kW (AC) and 24 kW (DC) charging points in the customer car park that comply with calibration regulations.
These two semi-public stations from the manufacturer Compleo are available to employees and customers as well as third parties, with the latter being activated via RFID card. Soon, payment via credit card will also be possible there. The municipal utility is currently taking care of this, as well as regular operations management, maintenance, fault clearance and overall billing. Against this backdrop, the charging points are connected to the backend of the municipal company.