Renewable energy communities (RECs) facilitate the local synergy between different energy forms and offer an opportunity to couple electrical and thermal energy demands with local renewable energy sources and locally sited thermal and electrical storage. This application presents a complex integration setting for the assessment of hybrid energy storage, motivating the development of a new assessment and benchmarking framework. This chapter will revisit relevant electrical and thermal storage technologies suitable for REC integration and hybrid energy and storage systems. A benchmarking framework for application-level assessment of hybrid energy storage systems is proposed. Requirements and relevant KPIs for the REC application of a multi-domain hybrid storage system are identified. To demonstrate the benchmarking framework on the REC application, a complete reference implementation is presented, including configurable system inpucts, optimisation and simulation modules as well as a calculation module for performance indicators. A showcase of the reference benchmark is computed and analysed.