Energy communities approach applied to optimize polygeneration systems in residential buildings: Case study in Zaragoza, Spain

The residential sector plays an important role to combat climate change. It requires alternatives to reduce its energy consumption and greenhouse gases emissions. Thus, polygeneration systems are a suitable alternative enabling efficient use of natural resources with low environmental impact. On the other hand, microgrids are considered a key component for improving power reliability and quality, besides they offer resilient and viable solution for integrating renewable energy sources at a large scale. Accordingly, this paper proposes an approach for the design of polygeneration systems for residential buildings considering them not only as a microgrid but as a smart energy system. A Mixed Integer Linear Programming (MILP) model was developed for the optimization of polygeneration systems considering different constraints which allow the energy system to work as a microgrid. Different thermal and electrical technologies where evaluated under different conditions, finding affordable and sustainable configurations and interesting synergies between technologies. Results show the importance to consider both thermal and electrical demands and technologies simultaneously for the design of energy systems. It is highlighted the displacement of batteries by thermal energy storage to achieve more cost-effective solutions in contrast to the current tendency to uphold battery systems as the key for future energy systems.