The diagrams illustrate the design and function of two types of solar panel used to heat air and water.
Overall, it can be seen that both structures share a similar design that relies on solar rays. Each system consists of a box with a transparent top that allows sunlight to enter and transfer heat inside the boxes. It features two parallel but separate systems: one fore heating air and another for heating water, each one with its own inlet and outlet.
In the air-heating system, the solar panel designed to heat air includes a rectangular box with an inlet and an outlet. Cool air flows into the box through the inlet. In the box, it is heated via sun rays passing through the transparent top. Having been heated, it exits with the help of the outlet.
In contrast, the solar panel used for heating water involves the similar design and structure, but it also includes a coiled water pipe. Cool water enters the rectangular box through the inlet and travels through the coiled pipe. While travelling inside the box, it is warmed via solar radiation that has been absorbed by utilizing the transparent top. After that, the process results in warm water being discharged from the outlet.
To summarize, both solar panels function on the same principle of converting solar energy into heat. However, the key difference lies in their ways of doing it: one heats air directly in an open box, while another uses the coiled water pipe to heat water.