High power consumption demands a new energy concept
There were two reasons for choosing the building-integrated PV installation: it ensured the best possible solar yield, and there was no longer a need to purchase a conventional façade. “With the new PV installation, combined with the VARTA energy storage system, we can now use the highest possible level of own power from our solar power, as we had hoped, and as a result, reduce the amount of electricity drawn from the grid,” Klaus Mayer, CEO at Mayer, explains. According to Mayer, the initial experience at the company has been positive, and expectations have been met.
The new energy concept was developed by VARTA and WALTER konzept, a trans-regional engineering company from Ellwangen, which specialises in designing photovoltaic systems and the energy-efficient refurbishment of existing buildings. The core of the concept is a modern energy storage facility on a lithium-ion basis, which significantly increases local energy value and in so doing enables the machine manufacturing company to operate efficiently. The VARTA system can be adapted to fit local conditions, as Volker Dietrich, Sales Manager at VARTA, explains: “The output and capacity of the modular system can be cascaded. We configure the commercial storage unit with modern lithium-ion cells, which are optimised to the applications required in each individual case.” VARTA was responsible for simulating and designing the combined storage system. The energy concept and installation were provided by WALTER konzept.
The company’s energy transition in figures
The building-integrated photovoltaic installation has an output of 90.3 kWp and achieves an average annual yield of around 810 kWh/kWp. By contrast, anticipated consumption of electric energy is around 460,000 kWh. The newly installed lithium-ion storage facility, VARTA flex storage 36/75, has a charging and discharging output of 36 kW and a useful capacity of 75 kWh. The storage facility finally went into operation at the end of 2018. On average, the combination of PV installation and storage facility produces one kilowatt hour for 12 cents. Mayer anticipates revenues of around 396,000 euros within 25 years as a result of the savings on power consumption from the grid and the feed-in remuneration. The investment costs totalled around 206,000 euros. WALTER konzept calculated a return on investment in approximately 13 years. “The example with Mayer shows that the energy transition is increasingly becoming a reality in companies. Façade-integrated PV installations, combined with storage systems, offer an important pillar for the energy transition,” explains Wolfgang Walter, Senior Manager at WALTER konzept.