This paper reviews the various strategies and technologies for extending the lifetime of OWT, including advanced monitoring systems, maintenance techniques,
Lifetime extension is one of many options available to a wind farm owner and the results of a lifetime assessment are key to developing effective lifecycle strategies. Structural component fatigue accumulation is a key concern for wind turbine life extension. To understand the lifetime of a particular structural component, the knowledge of component strength margins is key. However, this information is typically not available to the wind turbine owners. Strength margin is the gap between the load level that would risk causing structural failure and the ‘design loading’ level used to dimension the wind turbine components. Whilst turbines are designed to wind ‘type’ classes as defined by the standards which translates to a particular ‘type class’ load level, often additional margin can be found at different structural component locations for a variety of reasons:. * Component design strength may be governed by extreme loading and therefore have significant margin to the design fatigue loading.
DTU Wind Energy E No. E-0196 1 DEMONSTRATION OF REQUIREMENTS FOR LIFE EXTENSION OF WIND TURBINES BEYOND THEIR DESIGN LIFE (LifeWind) Anand Natarajan, Nikolay Dimitrov, Dheelibun Remigius Technical University of Denmark Leonardo Bergami, Jens Madsen Suzlon Niels Olesen, Thomas Krogh Ørsted Jannie Nielsen, John Dalsgaard Sørensen Aalborg University Mikael Pedersen, Gyde Ohlsen European Energy Jens Lund Lauritsen ALLNRG Pernille Daub Danish Energy Agency Michael Steiniger, Erik Jørgensen DNV GL Xavier Vives Siemens Gamesa Strange Skriver Nordic Wind Consultants Gregory Simmons, Reza Ahmadikordkheili Vattenfall Flemming Selmer Nielsen, Søren Bruun R&D A/S Project Final Report Project no 64017 -05114 Funded by the Energy Technology Development and Demonstration Programme (EUDP) ISBN: 978-87-93549-64-7 DTU Wind number: DTU Wind Energy E-0196 2 Executive Summary ---------------------------------------------------------------------------------------------------------------------------------------- 5 1.
permission is required to reuse all or part of the article published by MDPI, including figures and tables. Feature papers represent the most advanced research with significant potential for high impact in the field. Paper should be a substantial original Article that involves several techniques or approaches, provides an outlook for. + PESTLE Analysis for Lifetime Extension of OWTs. + Lifetime Extension Process for OWTs. The objective of this paper is to present a detailed PESTLE analysis to evaluate the various political, economic, sociological, technological, legal, and environmental challenges that must be overcome to successfully implement lifetime extension projects in the offshore wind energy sector. We propose a decision framework for extending the lifetime of OWTs, involving the degradation mechanisms and failure modes of components, remaining useful life estimation processes, safety and structural integrity assessments, economic and environmental evaluations, and the selection of lifetime extension technologies among remanufacturing, retrofitting, and reconditioning.
For fatigue maximum stress isn't the concern, the range of stresses induced is used to calculate fatigue life. You will need S-N (stress range
The calculation results show that the fatigue life of the tower is 31.2 years when the ideal S-N curve is adopted, the fatigue life of the tower is 26.7 years,
When the design basis and general operational history of the turbine are available, includ-ing power production, wind speeds, and rotor speeds as commonly recorded in the SCA-DA system, a probabilistic design approach at the turbine level can be followed to estimate the remaining expected life of the structural components and the frequency of inspection required for different turbine components. The evaluation of remaining life will require an assessment of the site-specific component loads, based on the turbine’s operational history and measured wind conditions, along with a probabilistic analysis contingent on the current structural condition and the impact of possible material degradation on the structure’s fatigue-limit state.
The following additional information is useful to inform the analysis: • Operating schemes, such as wind sector management, curtailment, derating or upgrades e.g. power boost etc.; • Component failure history (if available including records from other wind turbines of the same type); • Maintenance activity history; • Fault and downtime history including emergency stop (and start) statistics; and • Impact of any historical severe events, such as hurricanes and earthquakes 8 3 Wind Turbine Inspections 3.1 Objective The primary objective of carrying out physical WTG inspections as part of a LTE assessment is to assess the condition of the WTG’s critical structural components to determine if they are fit to continue operating safely beyond the design lifetime (i.e. 20 years) and to validate any assumptions made in the analytical analysis.