Impact of vessel logistics on floating wind farm availability

Abstract

ABSTRACT: This paper presents a study of the impact of the Operations and Maintenance (O&M) vessel logistics over the power availability of an Offshore Wind Farm. In particular, the vessel size and availability are considered. The study is performed with a life-span simulator, based on historical metocean data, walk-to-walk characterization based on a frequency domain hydrodynamic modelling of multibody systems, wind farm fault simulator (based on a catalogue of more than 1800 faults) and an algorithm to reproduce the O&M intelligence (i.e. sea transportation, workability, among others). The frequency domain model is applied on an hourly basis considering the specific significant wave height, peak period, peak enhancement factor, mean heading, directional spreading, and a wave-by-wave strategy is used to find if personnel transfer and workability criteria are met. The WindFloat Atlantic wind farm, located off the coast of Viana do Castello (Portugal), was chosen together with the TRL+ project semi-submersible platform and the 10MW turbine as a reference case. Different vessel logistics options are compared, including full vessel availability and several options of waiting times. The power availability changes among the different cases of study could be compared with the cost changes, optimizing the LCOE (Levelized Cost of Energy) of the wind farm. The presented study is a valuable example of the potential of the proposed O&M simulation model as an optimization tool.