Combined cycle power station, Herne

The new Herne 6 combined gas and steam cogeneration plant at the Herne Strom power station has been generating electricity since the beginning of 2022. PORR worked under contract to general contractor Siemens Division Power & Gas to establish a secure foundation for this project. Our specialist civil engineering team manufactured 777 Frankipfahl NG® piles in an outstanding demonstration of adherence to schedule, economic efficiency and CO₂ reduction.

Ready for the hydrogen future

The gas plant generates power in a combined heat and power (CHP) system, in which over 85% of the fuel used is natural gas, while simultaneously providing a reliable supply of district heating for the Rhine-Ruhr region. The Herne cogeneration plant is one of the most efficient and resource-conserving power stations in the world. Plans are already in motion to introduce hydrogen firing to the system in future. An extra climate-friendly feature of the project was the short transport distances required for the key components. The steam turbine and generator were manufactured in the neighbouring town of Mülheim, while the gas turbine came from the Siemens factory in Berlin.

Investigating load bearing capacity with pile test loading

The actual foundation works were preceded by

pile test loading processes in June and July 2019. During this period, two test piles were subjected to dynamic pile tests, static pile tests under pressure and horizontal static pile tests to confirm the load bearing requirements of the project could be satisfactorily met. All tests were successful. In fact, the planned loads were so safely transferred that the pile design was able to be further optimised.

Economical and resource-efficient foundations

A total of 777 Frankipfahl NG® piles were inserted to a penetration depth of approx. 16m into the marl soil to create the pile foundation of the plant. Once construction was complete, the quality of the concrete and manufactured piles was documented with the use of pile integrity testing. Due to sophisticated cycle planning, the team was able to reduce the planned execution time by three weeks. The optimisation proposal presented by our foundation experts also reduced the volume of concrete required by around 6,000m³. Less concrete used and less borehole cuttings to remove meant saving more than 800 transport loads. Ultimately, the Herne combined cycle power plant foundation project was completed in an economical fashion and with an outstanding CO₂ balance sheet.