The income side of wind farm operation is solely determined by the amount of wind, isn’t it? In principle, yes – but only if the wind turbines (WTs) are operating optimally and the maximum efficiency is always attained. In order to achieve this aim, the German company GEO mbH uses the Inspector.
The Inspector Performance Check consists of a differentiated analysis of the operation data from WTs at a wind farm (in exceptional cases also single turbines), to identify weaknesses in generation behaviour. Using self-developed, science-based algorithms and procedures, the 10-minute average values from the turbines’ data stores are looked at in detail. From this information, gathered on-site under real operating conditions, power curves can be generated with the aid of various programs and numerical filters, which then serve as the basis for the assessment.
The assessments are both individual and complex. Site geometry and external factors must be taken into account just as much as uncertainties resulting from the positioning of the nacelle anemometer, used for making wind speed measurements, behind the area swept by the rotors. It is not unusual for several hundred thousand data pairs to be repeatedly sent through various computer routines. An overview of the steps taken can be found on the GEO homepage (http://www.geo-mbh.de) by clicking on the Inspector button.
At the end of this, results are obtained which are then analysed by the experts in the energy-meteorological and technical departments. Significant conspicuities, pointing to a sub-optimal performance of WTs, are identified and described. In addition, possible causes are defined and passed on to the client in the detailed reporting process. If desired, GEO can help with the implementation of technical procedures, either actively or as a consultant.
When is the Inspector, with costs in the region of those for a wind survey, worthwhile? Anyone who can’t be sure that the control systems and components of all the WTs are optimally set up to work with one another, may possibly be losing income. Even an increased yield of a few percent, at an average site and with a high enough rated power, can mean a five-figure increased income – per WT and every year!
Fig: Optimised power curve of a 2000 kW WT based on an Inspector Performance Check.