Ocean Current Patterns and Variability around Curaçao: An Analysis for Ocean Thermal Energy Conversion

Abstract

The implications of installing and operating an Ocean Thermal Energy Conversion (OTEC) plant on the large temporal and spatial scales of the oceanographic features and the interaction between them are yet unknown. The aim of this research is to describe the natural patterns and variability of the ocean currents around Curaçao, an island in the Caribbean Sea and a potential OTEC location, to be able to assess possible risks and opportunities for the OTEC industry. Ten years of data from the Mercator Ocean Model with a spatial resolution of 1/12 ̊ and temporal resolution of one day was analyzed. In the Caribbean Sea, global ocean gyres and wind patterns force the water from the Lesser Antilles in the east towards the Yucatan Channel in the west in a fast-current jet, with a peak from December to March and a trough in October and November, related to wind stress. Largest surface velocities in the order of 1 m/s are found along the coast of Venezuela, where upwelling enhances surface flow to the west but subsurface countercurrents to the east. The period from April to September is characterized by meandering of the jet and the formation of large (diameter > 200 km) anticyclonic eddies that cause large local surface velocities and contribute to the great variability in the Caribbean Sea. Due to upwelling, no OTEC system should be deployed more than 50 km south of Curaçao to avoid cold surface water decreasing the system’s performance. Hydrodynamic forces and moments on the cold-water pipe due to calculated expected maximum velocities do not cause exceeding of the yield stress.