Grand Cayman’s Goal of 70% Sustainable Electricity: A Case Study

Abstract Renewable energy sources are a key technology for reaching net zero carbon emissions and reducing the contribution to climate change, but there are challenges and consequences of integrating large amounts into a grid. Grand Cayman is a Caribbean island with abundant solar resources and an ambitious energy policy, but neither the effect of the grid nor the implementation of the energy policy has been publicly modelled and analysed as of yet. In this research, the grid was modelled, and two solutions were designed and compared. The first solution was composed of mainly solar PV and aimed to follow the national energy policy while the second attempted to offer a stable base-load by using OTEC (Ocean Thermal Energy Conversion). The goal was to increase the share of DG (Distrusted Generation) to 70% of the island’s total electricity while not decreasing power quality. Both resulted in an improved voltage magnitude, power losses, and branch limits compared to the existing grid. This research provides a groundwork for further investigation to examine minute fluctuations throughout the day or seasonal changes throughout the year.