RWE AG (ETR:RWE), Ruhr University Bochum and engineering office Joerss-Blunck-Ordemann (JBO) are collaborating on a joint research project to explore the settlement of freshly recultivated land at former opencast mines and their suitability for wind power development much earlier than previously.
Typically, newly formed soils require several years to settle before they can be cultivated. Given the substantial weight of modern wind turbines, which can reach up to 6,500 tonnes, it is common for redeveloped areas to undergo a settlement period of up to 15 years before construction can take place.
As part of the research project, RWE and its partners will conduct tests at the Inden opencast mine for a duration of three years. Their aim is to select an area with the most complex subsoil conditions possible and commence there a field test, involving the placement of gravel and sand in a circular area equivalent to the radius of a wind turbine. The amount of earth used will match the weight of a wind turbine, including its foundation.
Geomechanical changes will be recorded by sensors embedded in the soil during this phase. Utilising data obtained from the field tests and accompanying geotechnical laboratory investigations, computer calculations will be conducted. The tests will help model the settlement of the subsoil under the static weight of the wind turbine and evaluate the impact of wind loads on the surrounding ground.
Torsten Wichtmann, Professor at Ruhr University Bochum commented: “We are confident that we can reliably assess the suitability of sites on freshly recultivated areas using computer simulations, which we want to confirm using the test fill in Inden.”
RWE aims to deploy 500 MW of renewables in the Rhenish mining area alone by the end of this decade.