Climate change is a real problem, which requires action atall levels to be tackled. In the field of energy, it seems essential to introduce renewablegeneration systems,bothcentralized and decentralized.Thus, communities can play an important role by generating their energy locally and from renewable sources.In this context, Santa Maria de Montserrat (or the monastery of Montserrat), a community located in the heart of the famous Catalan massif, wants to be part of the change and introduce renewable energies into its system.This project, which is part of a larger project called Smart Sanctuary,aimsto be a preliminary study to determine the potential of the integration of Renewable Energy Systems (RES)in Montserrat.This study consists of a techno-economic analysis, using the HOMER (Hybrid Optimization Model for Multiple Energy Resources) software,of a hybridgrid-connectedsystem that can be integrated in Montserrat’s current grid. Considering the community restrictions, an assessment of the available resources and technologies has been performed. To know the potential of different technologies, the indicators of systems with different architectures are presented and compared.The most interesting architectures from an economic point of view consider some PV systems but do not consider wind turbines andbatteries. These PV systems have a Levelized Cost of Electricity (LCOE) between 0.035 €/kWh and 0.05 €/kWh, and are able to provide around a 13% of the electricity in Montserrat, which is more or less what is consumed for the monastery and its residents. The winning architecture system have a slightly lower LCOE (0.1096 €/kWh) than the current system but they also include a natural gas generator, requested by the community in order to increase the reliability and resilience of the system. Finally, an economic,social and environmental sustainability analysis is provided in order to present the project and all its consequences to Larsa, group that represents the community of Montserrat.