Analysis of Cooling and Heating of Water with Flat-plate Solar Radiators

Extensive analysis of flat-plate radiative panels operation using average hourly weather data for a maritime climate region was performed. The panels are integrated in the space ventilation system with air-cooling by means of a cold-water coil. Their primary function is to prepare sufficient quantity of cold water, integrating radiative and convective cooling, that is collected in the cold-water tank during the nighttime operation. That cold water is used for cooling of the air during daytime. By small modification during daytime, solar panels could be turned into collectors and used to produce the hot water that is collected in a separate tank. A simulation model for the parametric analysis of the system in summer operating conditions and influence of its components on the system's operation was developed. The model includes the control of the systems's operation, which prevents water circulation in the periods without cooling/heating contributions. The purpose of this research was to predict the system behaviour in Irish climatic conditions, to enable sizing and design of the test rig that is to be built for experimental validation as part of a current large research project. The results were presented in the appropriate charts, where the influence of the main parameters on the system's operation was illustrated. The results showed that the same system, with small modifications to the physical set-up, could provide a significant proportion of the hot water heating requirements in the daytime operation.