[en] In the context of achieving a decarbonized economy, wind farms installed farther offshore provide the opportunity of harnessing more stable wind energy. Exposed to the combined cyclic loading of wind and waves, offshore wind substructures withstand, however, harsh fatigue and corrosion deterioration mechanisms throughout their operational life. In this scenario, Inspection and Maintenance (I&M) planning methods enable efficient control of structural failure risks by timely allocating inspection and maintenance interventions. In this work, we discuss the benefits of approaching I&M planning at the system level, thus determining strategies that are influenced by system risk metrics. To support the discussion, I&M policies are identified for an offshore wind support structure composed of 12 fatigue hotspots located at three weld connections and exposed to varying corrosion-fatigue deterioration intensities. Within the numerical experiments, the heuristics-based policy search is conducted both at component and system levels, exploring various structural redundancy settings. The results demonstrate that a systematic treatment of structural reliability can only be achieved by modelling the entire structural system, assigning and considering global failure risk metrics during the policy search. Independently of the investigated structural reliability model, system-based I&M policies outperform component-based strategies.
Research Center/Unit :
UEE - Urban and Environmental Engineering - ULiège
Disciplines :
Engineering, computing & technology: Multidisciplinary, general & others
Author, co-author :
Lacerda Giro, Felipe ; Université de Liège - ULiège > Département ArGEnCo > ANAST (Systèmes de transport et constructions navales)
MAXWind – MAintenance, Inspection and EXploitation Optimization of Offshore Wind Farms subjected to Corrosion-Fatigue
Funders :
SPF Economie - Service Public Fédéral Économie, PME, Classes moyennes et Énergie
Funding number :
R.ETAT.0634-Z
Funding text :
In April 2018, it was publicly announced that as part of the exit strategy from nuclear power, Belgium will double the area of its North Sea waters made available to offshore wind parks after 2020. After 2020, a new, 221-squarekilometre area near French waters is planned. This strategy clearly emphasizes the support of the Belgian government for wind energy as an important energy supplier for the future. In the near future there will be parks with different lifetime and this requires a sound lifetime assessment procedure to ensure the good functioning of the wind turbines and secure the energy supply. The steel support structures (jackets, monopiles) are subjected to both fatigue and corrosion, impacting their lifetime. There is a need for accurate lifetime assessment tools that can help offshore wind farm owners and operators to optimize the wind farm in the future lowering the Levelized Cost of Energy (LCoE) below 60€/MWh. This is of importance for the farms that are currently in operation and need an optimized maintenance strategy and possible extension of their exploitation, as well as for new projects which can also benefit from lifetime assessment tools in the design process. Belgian Energy Transition Fund (ETF)
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