E-mobility is the future. Latest figures clearly confirm this trend. The number of newly registered electric vehicles is increasing from year to year. In order to make this concept work, however, a good charging infrastructure is required in addition to the e-vehicles. The Dresen car dealership from Korschenbroich in North Rhine-Westphalia, Germany also wanted to make this accessible to its customers and employees, but the corresponding network connection capacity was lacking. The solution resulted in a comprehensive and individual overall PV system.
In the course of the mobility turnaround and the increasing demand for electric cars, more and more car dealerships are showing an interest in complete PV systems. This way, also the Dresen car dealership from North Rhine-Westphalia. The decisive factor for the decision to use green energy was primarily the planned e-charging infrastructure in connection with the existing low-voltage connection as the facts and the problem were obvious. The planned e-charging infrastructure of the car dealership with a total of eight charging stations, including a 50kW direct current fast charging station, achieves around 193kW at full power when all stations are used at the same time. The existing power connection, however, can only serve a maximum output of 150kW. It was therefore not possible to operate the charging stations. Adding more e-charging points is even unthinkable.
For the Dresen car dealership, there were basically two options of supplying the planned e-charging infrastructure and future expansion with sufficient power. A massive network expansion including an own transformer station or the investment in renewable PV electricity with a PV system, storage solution and energy management system. The latter was and is in the end not only the most environmentally friendly solution, but also the most economical and practical for the dealership. Therefore, since summer 2020, a total of 528 modules with an output of 167 kilowatt peak have been producing climate-friendly solar power on the roof of the dealership.
The complete PV system was specially adapted to the needs of the car dealership. In addition to the PV system with six inverters and an annual generation of around 135,000 kWh, the solution includes a commercial storage system with an output of 88 kW and a storage capacity of 131 kWh, eight charging stations and an energy management system (EMS). The interaction of all components and the intelligent control by the EMS now enable not only efficient use of the e-charging infrastructure, but also a high level of self-consumption of solar energy. With an annual electricity consumption of around 150,000 kWh, an upward trend, a self-consumption rate of around 60 percent can be achieved with the help of the complete PV system, which corresponds to around 80,000 kWh and means considerable cost savings. While the energy procurement costs and the company’s service charges decrease, the profitability of the dealership increases at the same time. Another plus point: With the combination of own PV use and storage, the dealership not only relieves the public power grid, but also saves around 61.6 tons of CO2 per year with its energy solution.
Conclusion: The energy and mobility transition needs a sensible coordination of regional generation and consumption based on demand. An electric car is the perfect tool to make this possible. From a statistical point of view, it stands still for most of its life and usually drives significantly less than 100 km a day.