1. Introduction and research hypoth

1. Introduction and research hypothesis1.1. Microgrids and distributed generationMicrogrids that employ hybrid energy storage systems have received significant attention in recent years as a means of exploitingdistributed renewable energy sources. They often incorporate multipletypes of equipment to transform different types of energy sources intopower (e.g. Photovoltaics, Wind generators etc.), while commonlyconsidered storage options include batteries or hydrogen infrastructure,to name but a few [1–4]. Storage is very important in order to enablehighly intermittent energy sources to be seen by the grid as dependablepower flows. However, together with different energy transformationoptions they result in the need to combine equipment of heterogeneoustechnical and temporal operating characteristics. This causes significantcomplexities pertaining to the selection of the appropriate energytransformation or storage option, of the amount of energy to be transformed or stored and of the appropriate time instant to initiate or terminate the operation of the corresponding equipment [5]. Furthermore,such systems are often required to serve multiple different loads whichare driven by variable and often difficult-to-predict demands [6].To address these challenges, published research includes a widecollection of works on energy management of the power generation[7,8], storage [9,1] and demand side response strategies of such systems [10]. Decisions regarding the equipment and energy carrier to use,the instant of their initiation and the duration of their operation areimplemented through Energy Management Strategies (EMS). The employed EMS either result from optimization approaches [10] or from apredetermined but non-trivial set of options [9,1].