Implementation of a solar-biomass system for multi-family houses: Towards 100% renewable energy utilization

The decarbonization of the building sector cannot preclude from the vast diffusion of renewable-sourced polygeneration systems for covering both heating and cooling demand. In this context, this study shows the potentialities of a system based on solar thermal collectors, a biomass boiler and an innovative reversible hybrid heat pump/ORC concept for addressing heating, cooling and domestic hot water demand of residential buildings. The potential is investigated in three cities (Madrid, Berlin and Helsinki), representative of the different European climates. The share of renewables in different seasons and building typologies is presented and the possibility of obtaining a 100% renewable system when the solution proposed is installed in new and renovated buildings is discussed. The results show that in standard multi-family houses, up to 70% of heating demand and 100% of cooling demand can be covered by the system in warmer climates and up to 60% share of renewables can be reached in Northern climates. Moreover, the flexible configuration of the system shows the potential for the application in the future energy system of the EU.