New gas power plant, Leipheim

Gaskraftwerk Leipheim GmbH, based in the Bavarian-Swabian town of Leipheim and a 100% subsidiary of LEAG Energie Bergbau AG, is erecting a 300 MW gas turbine power plant in conjunction with experienced power plant construction company Siemens Energy and network operator Amprion. Due for completion by 2023, it will not participate in the electricity market but can be ramped up quickly at the network operator’s request as a special network resource (SNR) to maintain network stability. The South Region team from Stump-Franki Specialist Civil Engineering was commissioned to execute the pile foundations.

The challenge: high load transfer

Siemens Energy will not only supply the bulk of the systems technology, but will also assume operational management of the plant after commissioning. The plant will be able to provide 300 MW of electrical output within 30 minutes. It will be one of the first systems in the world to be operated exclusively digitally and remotely, requiring only a two-person day shift team on site.

Construction is taking place on the 250-hectare site of the former Leipheim Air Base, which has not been used for military purposes since 2008. The subsoil consists of layers of sandy, clayey loess loams, stable quaternary gravels at a depth of approx. 10 metres, and tertiary silts and clays from the Bavarian Upper Freshwater Molasse.

Green Franki piles for lower carbon emissions

The construction of power plants is subject to stringent technical specifications regarding the loads that are to be absorbed. The Leipheim gas turbine alone weighs 300 tonnes, so a highly precise pile design is required to ensure dependable distribution to the load-bearing layers. Static and dynamic pile load testing allowed the technical design and cost-effectiveness of the foundation method to be optimised in advance. Ultimately, 286 NG® Franki piles measuring approximately 12 m in length and with diameters of 51, 56 or 61 cm were used. These slender displacement piles also score highly in terms of sustainability: the carbon emissions associated with their manufacture were around 50% lower than the originally tendered pile system.

Thanks to comprehensive advance project and planning work, the Leipheim gas power plant will be built in just under three years. The tight schedule has kept the PORR team on their toes. By maintaining ongoing coordination with the client, this part of the project was completed on schedule before the groundbreaking ceremony.