Project Description

Pump-storage plant Leun

In 2012, we were assigned with the planning of the pump-storage power plant in Leun. These power plants have an important role to play – as currently the only option they are able to economically save energy on a large scale. The client had the goal to use the existing topographical gradient between Leuner Burg and Leuner surface mining 1 energetically. The topographical conditions concerning the necessary slope conditions are given with 340 m + NN ground elevation and a seawater level of 153 m + NN. As well as the required funicular water volume of ~ 450.000m³ in the upper and lower reservoirs.

A special feature of the pump-storage power plant Leun are the parallel arranged penstocks which allow constant pump- or turbine readiness. A small hydropower Pelton turbine set contributes  – at an excellent drop height – a small amount of water to generate base load, benefits both regionally and locally the nearby city of Leun. The pump-storage plant close to the river Lahn in Leun with 40 MW of installed capacity can feed secondary energy for 4 hours in the energy grid. It fits to be integrated into the landscape of future German energy revolution. The Hermann Hoffmann Group intends to establish a regional grid with its wind turbines and the pump-storage plant (PHS) and is in the final phase of the approval process.

Project type

  • Client: Hermann Hofmann Renewable Energies GmbH & Co. KG

  • Construction and operation of a pump-storage plant

  • Location: 35638 Leun near Wetzlar

Technical details

  • 40 MW PSP and 632 kW mini HEP

  • Penstocks: 2 x 2500 mm

  • Net drop height: 185-159m

  • Intake capacity at full load: Q T = 2 x 17.5 m³/s + 0.5 m³ s

  • Pump capacity at full load: Q P = 15 m³/s

Services performed

  • Overall Planning and Computing LP1-LP4

  • 3D laser scan survey

  • Cost Management

  • Surge analyses

  • Groundwater investigation

  • Power evacuation