Conference programme

Back to the programme printer.gif Print

Tuesday, 17 November 2015
14:30 - 16:00 Designing and operating for reliability
O&M & logistics  
Onshore      Offshore    

Room: Belleville

This session will show the latest studies carried out for analysing failure rates for wind turbine main components and sub-assemblies, both for offshore and onshore wind farms. Developments and a case study, in order to extend wind turbines life and solutions for avoiding catastrophic incidents, will be considered.

Learning objectives

Delegates will be able to:

  • Examine failure statistics for the major wind turbine sub-assemblies
  • Identify failure mechanisms for selected components
  • Recognise the cost implications of component failures
  • Define studies and strategies for extend wind turbine life
  • Analyse specific systems (converter, foundations) failures and behaviour for improving the performance
  • Failure Models and Effect Analysis applied to wind turbine sub-assemblies
Lead Session Chair:
Fernando De La Blanca, Ereda, Spain
Sergio Velez Gamesa, Spain
Sergio Velez (1) F
(1) Gamesa, Sarriguren, Spain

Share this presentation on:

Printer friendly version: printer.gif Print

Presenter's biography

Biographies are supplied directly by presenters at EWEA 2015 and are published here unedited

Mechanical Engineer and Master in Business Innovation. He has been working for the last 15 years in the wind industry. He has carried out different executive positions with several patents in Blade Engineering. For the last 4 years he has been leading the Wind Farm Aging processes and Life Extension Programs. Sergio also participates at the European Commission Energy projects, at the Safe Life Ex project. This project aims to develop the new technologies and standards to perform the life extension of the European infrastructure such as power plants.


Wind Turbine Ageing Management


Today service life of Wind Turbines (WTs) is restricted to 20 years’ service. Although WTs manufacturers have preventive maintenance programs, no specific strategy exists to properly address aging WTs. In the US, Denmark, Germany and Spain, more than 50% of the current installed based will be over 15 years old in 2020, making life extension a real opportunity, but also a technical challenge


Life Extension is not economical if all turbines have to be regularly inspected and even less if components’ redesign implies corrective measures and not preventive actions. For this reason, Gamesa initiated a 4 years program to develop the technology and methods to ensure that WTG can be safely operated far beyond the original design life at a reasonable cost

Main body of abstract

Life Extension depends on the specific characteristics of each Wind Turbine model, site and history. A new methodology has been developed by Gamesa combining different sources (mathematical model, Operational data, Site data such as orography and wind characteristics, usage of turbines, condition monitoring information, specific inspections, etc..) and computational improvements. Gamesa has been able to validate his life extension methodology with DNV-GL and thus create a new certificate, to be requested by banks, investors or authorities to validate life extension projects.

Gamesa has selected G47 platform, consisting on 2,743 Wind Turbines built up in different site conditions and most of them maintained for the last 17 years as a reference for its study . Every component of the load path has been analyzed in detail, studying the behavior of the hypothetical preventive and corrective solutions, either from the theoretical point of view or considering the components failure rate.

Gamesa identified different aging mechanisms and is able to propose for each turbine a tailored program that will limit the accumulation of fatigue in the structure without limiting the current annual energy production through wind sector management or nominal power de-rating


With this methodology, applicable not only on obsolete turbines but also on orphans’ assets, wind asset owners can operate safely wind turbines until year 30 at a minimum cost, lowering drastically the cost of energy of the installed fleet and of future turbines. Investors can now count on 25 or 30 years of revenues instead of 20 without increasing the original CAPEX. Thanks to this new methodology many European wind projects are economically viable despite the recent reduction or removal of some government incentives.

Learning objectives
With this presentation, the audience will learn about the different aging mechanism, which ones are the most critical and what the possible solutions are to overcome damages, even before they arise.

People will also realize the impact of Life extension and its certification in wind industry social acceptance and economics as government incentives are reduced or canceled.

Wind industry asset managers will also learn best practices from other owners on documentation and how to lower the future cost of such program.