The headquarters of the energy company STEAG GmbH, Essen/Germany (Figure 1), will gradually become climate-neutral in the coming months. The conversion to green, emission-free heating, which has already taken place, will now be followed by the installation of a photovoltaic (PV) system and an energy management system. In implementing this change, STEAG is drawing on in-house expertise from its subsidiaries STEAG Solar Energy Solutions (SENS) and OPTENDA GmbH. Together with the switch to green electricity, the measures achieve an annual saving in CO2 emissions of around 1,550 t.
STEAG is intensifying its efforts to steadily improve the company’s own carbon footprint. Since 1990, STEAG has already reduced its own CO2 emissions in Germany by more than 80 %. “The implementation of a detailed energy plan for our corporate headquarters in Essen is a further step along this path,” says Andreas Reichel, Chairman of the Management Board of STEAG, adding that the company is particularly proud that it can draw on in-house expertise to implement the plan.
Starting on 18th June 2022, the Würzburg-based PV specialists from STEAG’s subsidiary SENS is to install a rooftop solar system on an area of around 260 m2 at STEAG´s headquarter in Essen. This has a capacity of around 60 KWp. The more than 150 solar panels required will be lifted onto the roof of the building by a truck-mounted crane.
“In terms of area, an even larger and therefore more powerful PV system would have been conceivable,” says Michael Kollorz from STEAG’s building management. But since the building, which was designed by the well-known architect Egon Eiermann at the end of the 1950s, is a listed building, a larger system was not feasible.
A total of four inverters are installed to ensure that the system achieves an optimum energy yield even in the case of partial shading. The system itself is connected directly to the building’s main distribution board in the basement via a 70 m fireproof cable. “With the PV system alone, we will avoid around 22 t of CO2 emissions each year in the future,” says Bernd Retzlik, who supervised the implementation of the project at SENS.
The second important building block in improving the emission footprint of the building is the implementation of an energy management system. Here, too, STEAG can draw on expertise from its own ranks. STEAG’s digital subsidiary OPTENDA from Stuttgart has developed the “Energy Monitor”, a powerful and intuitive tool for energy monitoring and management. This is now also being used at STEAG´s headqurter in Essen.
The graphical display of the PV system’s performance data on a monitor in the building’s entrance area is only the most visible part of the new energy management system. “With the Energy Monitor, energy consumption can be easily recorded, analyzed and also optimized based on the results of those analyses,” says Sebastian Braun, Managing Director of OPTENDA. The name of the STEAG subsidiary stands for the task to which the young, digital team from Stuttgart has dedicated itself. “OPTimize ENergy by DAta”.
Thanks to the in-house software tool, the carbon footprint of the building is expected tobe improved by a further 61 t/a. “The conversion to a climate-neutral heat supply that has already taken place reduces the building’s emissions balance by a further 320 t/a,” says Kollorz. Finally, the bulk of the CO2 savings comes from the switch to green electricity. “This measure accounts for at least another 1,150 t/a.
The energy plan for STEAG’s headquarters was developed by an interdisciplinary working group of management trainees. Traditionally, these junior managers go through a General Management Program (GMP) at STEAG. In that program, the participants work in teams to develop a project of their own design. “The idea behind the energy plan was to create a practical benefit for the climate and the environment. In addition, the project was also intended to symbolize the fundamental transformation of STEAG, which the company, which for decades stood primarily for energy generation from hard coal, is currently undergoing,” explains Florian Dauber, one of the members of the project group.
“With the implementation of the energy plan, STEAG is documenting its declared intention to gradually reduce its own emissions further and further,” says Ralf Schiele, who is responsible on the STEAG Board of Management for the Market and Technology divisions.
But even beyond the immediate climate benefit, the project has an important significance for STEAG: “In addition to the immediate effect for the benefit of our climate, the project is also an important technical reference for the solutions STEAG has to offer in the comprehensive decarbonization of industry and commerce,” says Schiele. (STEAG/Si.)
