Dimensionless and thermodynamic modelling of integrated photovoltaics-air source heat pump systems

It is necessary to know the max photovoltaic power generation and the thermodynamic performance of the integrated system when the photovoltaic system is integrated with the air source heat pump (ASHP). A dimensionless method to model the max PV conversion efficiency of the monocrystalline silicon cell by the light intensity and environmental temperature has been introduced in this paper. To evaluate the validation of the engineering application of the dimensionless model, exergy efficiency and exergy consumption cost of the integrated PV driven ASHP system (PV-ASHP) have also been modelled based on the max PV conversion efficiency. The dimensionless model of a PV module was developed based on the ambient air temperature and light intensity in the laboratory. The max difference between the actual values and the prediction values is less than 0.28%. The dimensionless model can be used in the practical application in Central-south China with a modified factor of 0.75. The results of a case study in Changsha, China show that the relative error of the exergy efficiency model of the integrated PV-ASHP system is less than 4.21%. The relative error of the exergy consumption cost model of the integrated PV-ASHP system is 1.5% for cooling and 0.3% for heating. The results illustrate the accuracy and the validity of the dimensionless model and thermodynamic model for validating the PV-ASHP system. The dimensionless method provided in this paper also could be used to predict the different types of PV modules such as the polycrystalline silicon photovoltaic cell. The thermodynamic model of the integrated PV-ASHP system also could be used to investigate the efficacy of the integrated PV-ASHP.