Hybrid Roof Panels for Night Cooling and Solar Energy Utilization in Buildings

The aim of this contribution is to evaluate the usability of solar hybrid panels, which were originally optimized for heat load removal from buildings by radiation against the night sky, for water preheating. First we created a surrogate model based on CFD simulations defining performance of the panel dependent on changing boundary conditions. This model was then implemented to the water heating model created in TRNSYS software. Estimated hot water usage would suffice for operation of 2 restaurant facilities in a building of our interest. Subsequent simulations were carried out using reference year climate data for Brno (Central Europe). Results demonstrated that in the given conditions, the average annual efficiency of solar energy usage is 55%. The results also showed that the system is able to cover approximately 7% of the heat demand for water heating.