The joint project ”Objective criteria for vibration and sound emissions of onshore wind turbines” (TremAc for short) has investigated the effects of infrasound and ground vibrations. In 2012 and 2014, researchers analysed the effects of sound. In 2018, the TremAc project focused on low-frequency sound (including infrasound) and seismic waves (ground vibrations).
In the study, which was funded by the German Federal Ministry of Economic Affairs and Energy, the researchers could not plausibly prove a connection between acoustic or seismic waves and physical or psychological complaints.
The cluster carried out research at the Wilstedt wind farm near Bremen, analyzing wind energy immission effects on acceptance, well-being and health of local residents. The Karlsruhe Institute of Technology, the University of Stuttgart, the Technical University of Munich, the University of Bielefeld, the Martin Luther University Halle-Wittenberg and the company Mesh Engineering participated as project partners. Enercon supported the study as the turbine manufacturer, and wpd windmanager as the operating manager of the Wilstedt wind farm.
For the study, residents of the Wilstedt wind farm and the Ingersheim wind turbine were interviewed. The symptoms expressed could only be traced back subjectively to a WTG operation. “The low-frequency sound amplitudes that could be attributed to the turbine operation were extremely low”, explains Dr. Johannes Pohl, psychologist at the Institute for Psychology of the Martin Luther University Halle-Wittenberg. “And the measured ground vibration velocities also showed amplitudes that were many times below the human perceptibility limit. This makes it unlikely that these types of waves could trigger stress effects or be a reason for perceived annoyances.”
The results of the TremAc study could be groundbreaking for wind energy in Germany”, says Dr. Pohl, “because they contribute to an objectification of the discussion about ground vibrations and infrasound. However, further research will be necessary for this – on the one hand to create an even more wind farm-specific database and on the other hand to better understand the physical and psychological factors that can contribute to nuisance.”