Hekimoğlu, MustafaSchouten, Thijs NicolaasDekker, RommertHekimoglu, MustafaEruguz, Ayse Sena2023-10-192023-10-192022170377-22171872-6860https://doi.org/10.1016/j.ejor.2021.09.004https://hdl.handle.net/20.500.12469/5132In this paper, we introduce a new, single-component model for maintenance optimization under timevarying costs, specifically oriented at offshore wind turbine maintenance. We extend the standard age replacement policy (ARP), block replacement policy (BRP) and modified block replacement policy (MBRP) to address time-varying costs. We prove that an optimal maintenance policy under time-varying costs is a time-dependent ARP policy. Via a discretization of time, the optimal time-dependent ARP can be found using a linear programming formulation. We also present mixed integer linear programming models for parameter optimization of BRP and MBRP. We present a business case and apply our policies for maintenance planning of a wind turbine gearbox and show that we can achieve savings up-to 23%.(c) 2021 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )eninfo:eu-repo/semantics/openAccessModified Block-ReplacementMinimal-RepairModelsPolicySystemsModified Block-ReplacementMaintenanceMinimal-RepairAge replacement policyModelsBlock replacement policyPolicyTime-varying costsSystemsOffshore wind turbineArticle9799913300WOS:00078172800001310.1016/j.ejor.2021.09.0042-s2.0-85116688929Q1Q1