Survey of Failures in Wind Power Systems With Focus on Swedish Wind Power Plants During 1997–2005

TLDR

The wind power industry has expanded rapidly, with larger turbines and offshore deployment, yet many new designs are inadequately tested and their projected 20‑year lifetimes are rarely met, leading to operational challenges. This study investigates failure statistics of wind turbines using data from Sweden, Finland, and Germany. The authors compiled failure data from two Swedish, one Finnish, and one German source to analyze component reliability. The analysis shows the gearbox as the most critical component due to high downtime per failure, and indicates that larger turbines exhibit increasing failure rates over time while smaller turbines display decreasing rates.

Abstract

The wind power industry has expanded greatly during the past few years, has served a growing market, and has spawned the development of larger wind turbines. Different designs and technical advances now make it possible to erect wind turbines offshore. The fast expansion of the wind power market faces some problems. The new designs are not always fully tested, and the designed 20-year lifetime is typically never achieved before the next generation of turbines are erected. This paper presents results from an investigation of failure statistics from four sources, i.e., two separate sources from Sweden, one from Finland, and one from Germany. Statistics reveal reliability performance of the different components within the wind turbine. The gearbox is the most critical, because downtime per failure is high compared to the other components. The statistical data for larger turbines also show trends toward higher, ever-increasing failure frequency when compared to small turbines, which have a decreasing failure rate over the operational years