Optimal sizing of Battery and Hydrogen Energy Storage Systems configurations in a Hybrid Renewable Microgrid

Abstract

Considering the increasing penetration of variable and non-dispatchable renewable energy in worldwide electricity mixes, an increasing requirement for energy storage capacity is foreseen in order to decouple production and demand. Electrochemical battery systems and/or hydrogen systems (electrolysers and fuel cells) provide a suitable alternative to be implemented in local small-to-medium scale microgrid environments. The research aims to address the optimal sizing of an Energy Storage System composed of lead acid batteries and a hydrogen loop (electrolyser, compressed storage tank and fuel cell) within an actual hybrid renewable microgrid located in Huelva, Spain. The energy storage systems must couple the variable production of 15 kWp of solar PV systems and a 3 kWnom horizontal axis wind turbine to a real monitored residential load, which present a time-shifted power demand. By making use of previously developed and validated component models, three storage configurations (battery-only, hydrogen-only and hybrid batteryhydrogen) are assessed via parametrical variation in yearly simulations in hourly timestep, analysing the Loss of Load (LL) and Over Production (OP) output values. The results provide quantitative information regarding the optimal storage system capacity in each configuration providing valuable insight in terms of sizing of the energy storage systems in the long-term.