Lifetime extension

1,200 wind turbines approved with over 11,000 years of extended lifetime


Assessment and verification for lifetime extension (LTE) of wind turbines

The operating time of a wind turbine/wind farm can be extended with the assessment for lifetime extension after the expiration of the designed service life. The prerequisite for lifetime extension is proof that the wind turbine can also be operated safely in the future and that its structural integrity is guaranteed in accordance with current regulations. We analyze the type approval and check whether it continues to comply with currently valid guidelines after the expiry of the designed service life.

The process of evaluation and assessment for lifetime extension of wind turbines is divided into an analytical part (determination of the calculated remaining useful life, component by component) and a practical part (on-site inspection) and thus follows the “Principles for the performance of an assessment and verification for lifetime extension of onshore wind turbines” of the German Wind Energy Association (BWE).

The result of the inspection for lifetime extension is explained in an expert´s opinion report and the remaining useful life is confirmed in a certificate.

Professional analytics for LTE

Proof of structural integrity for more than 1,200 WTGs to date in accordance with DIBt guidelines and the BWE principles.

Well-founded competence from more than 30 years of experience in load simulation of wind turbines for detailed/sustainable analytics for lifetime extension (LTE).

Multiple successful assessment of our analytic reports by competent support in the attendance of authority evaluation.

"Cooperation lifetime extension": Cooperation with the specialists of the expert offices of the ‘Windexperts network‘ to fulfill the practical part and final overall report on lifetime extension.

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In the analytical part, it is determined by calculation when load-bearing components reach the limits of their service life. The remaining useful life is calculated from the loads that actually occur in comparison with the loads under design conditions for which the manufacturer designed the plant and dimensioned the components.

Downtimes as well as yield results and operation times are also included in the calculations. The basis for the simulation of the site loads is a turbulence report, which must be included in the analysis. In this way, loads resulting from a prolonged operation as well as loads according to design conditions can be simulated.

With this method and our experience, the remaining useful life of the wind turbine can be precisely determined component by component and the time period for safe prolonged operation can be assigned.

Foresighted continued operation

In consultation: general analysis or consideration of individual needs

Precise determination of the remaining useful life on a component-by-component basis.

Principle of "weakest link in the chain": Additional possibilities for component replacement to extend the remaining useful life are identified.

Significant increase of remaining useful life if required, by individual component evaluation by means of FEM calculation.

Expert opinion / expertise / report

Comprehensive, verifiable analysis report incl. description of the procedure and presentation of the results in numerical and graphical form as proof of the structural integrity for submission to the responsible building authority as a PDF (length approx. 60 pages). Report language: German, English, other languages on request.