Optimization of Road Solar Thermal Collectors Coupled to Borehole Thermal Energy Storage for Annual Climatization of a Multiplex Cinema in Italy: An Energy and Economic Analysis

The European Union has set an ambitious goal of achieving net-zero emissions by 2050, and 90% reduction by 2040, through its Green Deal policy. A promising solution to this challenge lies in the adoption of Fifth-Generation District Heating Networks (5GDHNs) that operate at low temperatures, collecting and distributing heat from diverse sources (energy geostructures, asphalt pavement solar thermal collectors, industrial waste heat and waste heat from buildings’ cooling plants). The system’s design allows for heat storage underground, primarily during summer months, with distribution occurring via pipelines during winter. As part of the REHEAT project, a study has been conducted focusing on a simulation model developed using TRNSYS software. This model incorporates solar thermal collectors installed beneath the parking area asphalt pavements as a thermal energy source, coupled with a borehole thermal energy storage system. The setup is designed to meet the heating and cooling demands of a multiplex cinema situated in Northern Italy. The study presents the optimization of the system, reporting the monthly and annual data on energy balances and system efficiency. The findings demonstrate significant energy savings when compared to traditional heating and cooling systems (50.6% non-renewable primary energy reduction) and even greater CO2 emission reduction (63.2%). Also, the economic analysis reveals positive results both from the point of view of operating costs and taking into account investment costs, highlighting the potential of 5GDHN as a sustainable solution for urban energy needs for a real case as the main novelty of this study.