In just ten weeks' time, a 24500 m² photovoltaic array of 9384 modules was established atop the production hall at Röben's clinker plant in Bannberscheid. During optimal, simultaneously insolation on all modules, the theoretically achievable output peaks at 2346 kW. By way of comparison: running at full load, the Bannberscheid plant needs approx. 1650 kW. The annual power output is situated at roughly 2 million kWh, which corresponds to the amount of electricity consumed per year by roughly 500 households. The CO2 emission reduction effect stands at 1.28 million kg/year. The installation not only reduces the plant's daytime purchased power consumption, it also feeds its surplus output into the local grid.