Abstract
In recent years, ocean currents have been identified as a promising resource for renewable energy generation. However, most conversion devices remain at an early stage of technical development, hindering progress towards large-scale commercial deployment. In this scenario, the resource assessment, with particular attention to hydrodynamic characterisation, re-emerges as an essential activity that demands comprehensive knowledge to meet the requirements of any generation project and to support the reduction of the cost of energy. The present research aims to evaluate the energetic potential of an ocean current located in the insular shelf of Cozumel Island, emphasising on the definition of the fundamental parameters needed for the hydrodynamic design of a medium-scale horizontal-axis hydrokinetic turbine with a radius of about 0.5 m. The evaluation was divided into two main sections. In the first section, 192 current speed time series were obtained from the HYbrid Ocean Coordinate Model (HYCOM), each associated with a geo-referenced node and a depth of 50 m. Subsequently, the K-Means++ algorithm was applied to cluster nodes based on their statistical features. Three specific approaches were considered for the feature extraction: statistical moments, principal component analysis, and deep autoencoding. The clusters were compared using the Silhouette, Davies–Bouldin and Calinski–Harabasz scores. While the first and second approaches produced quite similar and consistent results, the performance of the third approach was unexpectedly inferior. In the second section, four potential harnessing regions were chosen. For each region, the optimal power per node and cluster was computed using 25 generic power curves. It was assumed that nodes within the same cluster shared a single optimal curve. For the most promising region, the best-performing power curve suggests a cut-in speed of 0.69 m/s, a rated speed of 2.3 m/s and an effective speed for hydrodynamic design of 1.52 m/s. The maximum capacity factor observed was 0.325, with a power production of 6.55 MWh/yr m^2. Although reported results focus on the maximum yield, alternative scenarios for power production are also discussed. Finally, a preliminary set of parameters to describe the operative state of the hydrokinetic turbine is presented.