Numerical simulation and parametric study of various operational factors affecting a PV-battery-air conditioner system under prevailing European weather conditions

The building sector currently accounts for approximately 40 % of final energy consumption. In the near future, renewable energy driven heat pump systems will play an important role in the thermal management of buildings. The work described here deals with the effect of weather conditions as well as operational characteristics on the energy and economic performances of a solar PV powered air conditioning unit (ACU) with a battery system (PBAS) based on numerical and experimental investigations. The experiments were carried out to test the developed TRNSYS model. In the assessment, various performance indicators were used while a novel performance indicator, the so-called annual grid independence ratio, was also proposed. The simulated studies revealed that annual energy performance indicators (self-consumption, self-sufficiency, grid independence and energy conversion ratios) are greatly affected by climatic conditions and operational characteristics. Besides, the economic analysis has shown that the net present value and the energy consumption profiles or diverging values for state of charges are directly proportional for the hottest (Seville) climate. However, they are inversely proportional for the coldest (Stockholm) climate for the considered PBAS configuration (PV-2.5 kWp, ACU-2.52 kW cooling and 2.84 kW heating, batteries-9.6 kW h) under the selected economic status of the sites.