Statistical analysis for evaluating the energy storage requirements of offshore wind and solar plants in the Mediterranean sea

Abstract

This paper presents a statistical analysis for two case studies involving offshore wind and solar farms coupled to an offshore Hydro-Pneumatic Energy Storage system. The analysis aims to estimate the energy storage capacity and the number of energy conversion units required by the storage system to smoothen the intermittent power from offshore wind and solar plants operating under Central Mediterranean Sea conditions. Furthermore, each case study considers three different average centrifugal pump efficiencies and power smoothing levels to determine the influence on the storage capacity requirements of the storage system. Results indicate that power smoothing plays an essential role in optimally sizing the system. Through the case studies performed, it is found that a 5% reduction in energy storage system availability (i.e., where demand is not met) can lead to capacity requirement reductions of up to 71%. Additionally, the inclusion of more than one RES indicates a greater need for storage. Results indicate that sensitivity to different simple moving averages can be reduced by including multiple renewable energy sources.