An application of multi-source heat pump system

The HVAC sector has seen in recent years the growing interest in using the so-called multi-source heat pump systems. This type of system aims to enhance the energy performances of the heat pump technology leading to a significant saving of primary energy. As already known in this field, the heat pump represents the best solution in terms of potential for the environmental decarbonization, energy efficiency and exploitation of renewable energies. The common heat pump systems usually exploit the air, water, or the ground as heat source and sink. The multi-source heat pump system uses different heat sources in one system. This approach could lead, for example, to the reduction of the ground heat exchangers field size which represents one of the main investment issues in GSHP system applications. In fact, sun and air can be used as alternative source to the ground during the middle season or when they are available and convenient, while the ground could be used during the peak periods of the seasons keeping good energy performances of the system. The present work summarises the results of a real large-scale experimental plant used for the air conditioning of a 100 m2 snack bar located in Ferrara, Italy. The energy and thermal behaviour of the plant has been monitored for one year. The data about the operating conditions in summer and winter has been analysed to evaluate the contribution of the different sources and the global efficiency of the system.