Experts from the University Center for Energy-Efficient Buildings of CTU designed, produced and tested the first prototype of a combined solar collector for heating a pair of heat-carrying substances water/air.
The idea of combining both types of technology into a combined solar collector for heating the pair of water/air heat-carrying substances resulted from the need to make high use of energy gains from solar radiation throughout the year and to maximize the operating time of the solar system.
A combined solar collector with the use of two heat-carrying substances is basically based on a situation typical for a mild and cold climate zone. In it, the level of solar radiation in the summer is sufficient for the preparation of hot water (50 - 60 °C), while in the winter the output temperatures from the solar collectors usually do not reach values higher than 30 °C. However, they may still be sufficient, for example, for heating cold ventilation air.
Based on the data obtained during testing, we performed a year-long simulation analysis. Its results confirmed the possibility of increasing heat gains from solar systems by up to 20% when using combined solar collectors.