Multi-criteria Analysis of a Residential Propane A-to-A Heat Pump integrated with Photovoltaic Solar Panels

To achieve the almost zero emissions goal by 2050, the residential sector will apply more stringent regulations as concerns the air conditioning appliances. According to the novel F-Gas regulation, in fact, the use and production of fluorinated gases will be further reduced until complete dismission by 2035, paving the way for the exclusive use of natural refrigerants, such as propane, which has proven to be particularly promising for these systems. Moreover, the use of self-produced electric energy in the residential sector by means of renewable sources such as photovoltaic panels will be more and more promoted in the next future to cope with the concept of energy communities. However, complex solutions may not always be economically competitive, especially for small-size appliances, and the environmental sustainability in terms of total equivalent CO2 emissions of the global system should be carefully verified. In this context, the paper presents a multi-criteria analysis of design configuration for a 2.5 kW residential split heat pump working with propane and driven by polycrystalline solar panels. Dedicated models are developed and employed for each component of the air conditioning appliance and for the photovoltaic panels. Multiple scenarios in terms of severity of refrigerant leakages (as most common malfunctioning occurring in these systems) are also examined. Simulations are run by exploring several geometrical solutions for the heat exchangers and different sizes of the solar panels installed, in order to estimate and discuss the system performance in terms of two opposing criteria, being the economic (total costs) and environmental (total CO2 emissions) ones.