Energy and economic sustainability in the renewal of centralized heating systems using hybrid heat pump systems

In the context of the energy transition policies desired by the EU, the objectives set by 2030 include the reduction of greenhouse gas emissions, the achievement of greater energy savings and the increase in the use of renewable energy. This study, after an analysis concerning the Italian building stock, aims to highlight a possible first step towards achieving these objectives: the renewal of centralized heating systems in multi-dwelling buildings. In fact, on the national scenario there are about 430,000 condominiums with centralized heating system built before 1990 and, therefore, possibly liable to energy efficiency. In this research a case study building was simulated using the software EnergyPlus in which a renovation of the existing heating system was modelled in the Matlab/Simulink environment with an innovative hybrid generator consisting of an air/water heat pump and a condensing boiler. The analysis of this solution, carried out for three different Italian climatic zones, highlights how significant reductions in CO2 emissions can be achieved, high energy savings in terms of primary energy use and savings regarding usage costs, thus achieving greater comfort and sustainability. In addition, an economic analysis was carried out comparing different combinations of systems with the aim of identifying the best solution for each application