How Solar Thermal Systems Work
Solar Thermal systems capture the sun’s rays into heat, therefore raising the temperature of water to the desired utility. The solar system is comprised of several components, most important of which are the collectors that are classified under two main types – flat plate and evacuated tube type. The selection of the collector type is established based on several factors which includes performance and cost. The conversion efficiency of a solar thermal collector is influenced by the ambient temperature conditions, the amount of solar radiation, the temperature of the fluid inside the system, and the design of the entire solar system.
The collector alone cannot do the job, whereby heat is transferred to the required user at a set temperature, often in harmony with back-up heating systems such as electric calorifiers or boilers. There are many variations and design considerations in solar thermal systems – such as closed loop or drain back type – each customized to address the specific needs of a project in order to maximize the total output of the system, manage stagnation, and ease of operation and maintenance. The balance of plant is often comprised of circulating pumps, heat exchangers or double coil tanks, hot water storage tanks, expansion vessels and custom control systems.