Field measurements

© Jan Meier

The rapidly growing competition in the wind energy industry demands high-quality, efficient processes enabling prototypes and installed wind turbines to be measured, analyzed and optimized in the field. Developers, manufacturers, operators and technical service providers as well as banks and insurance companies require reliable information regarding the efficiency, functionality and life-time perspective of their wind turbines. The Application Center for Wind Energy Field Measurements, AWF, a cooperation between Fraunhofer IWES and fk-wind:, offers services for the measurement of operating wind turbines.

AWF has highly qualified scientific and technical staff at its disposal and is accredited according to ISO 17025 for mechanical loads measurements on wind turbines.

AWF is integrated into the Fraunhofer IWES organization and works closely together with the University of Applied Sciences Bremerhaven, benefitting from access to a unique testing infrastructure as well as established cooperations for applied research. This allows the field measurement activities of both institutions to be bundled and ensures that projects are carried out efficiently. The  Application Center for Wind Energy Field Measurements is supported by the European Regional Development Fund/State of Bremen.

The key tasks of AWF are:

Implementation of standardized and customer-specific measurement projects on operating wind turbines

Technical support for measurement campaigns as part of both institutes’ research and development projects

Further development of sensor technology and methodology for wind turbine field measurements


Application fields


Certification measurements and validation of simulations

Comparison measurements for rotor modifications

Load monitoring for reducing operating costs and for improved lifetime extension calculations

© Foto: Jan Meier

Description of measurements

Following consultation with the customer, AWF applies the relevant national and international standards and guidelines. For example, the following load parameters are measured according to IEC 61400 – 13:

  • Flap-wise und edge-wise bending moments at the rotor blade root
  • Bending moment and torsional moment at the rotor shaft
  • Bending moment and torsional moment at the tower top and base
  • Accelerations at the tower top

Data analysis and interpretation are enhanced by acquisition of essential operational wind turbine data such as wind speed, electrical power, azimuth position and rotational speed. Furthermore, AWF offers to carry out special measurement campaigns on specific wind turbine components using strain gauges as well as customer-specific electrical and mechanical measurements. When required, the extensive experience and competence of Fraunhofer IWES and fk-wind: can be integrated into the process.

Accredited for testing of mechanical loads on wind turbines