In a nutshell, solar hot water panels collect heat from the sun and use it to warm up your water. However, unlike solar electric panels, those used for heating water are not the same as those used to create electricity.
Solar water heating panels actually store heat from the sun and use it to warm the water directly.
Flat Plate Solar Water Heating Panels
This type of collector is great for those living in Arizona. A flat plate collector is usually made with copper tubes. These tubes hold the water and are fitted to flat absorber plates made out of copper. The whole assembly is contained inside an insulated box with a glass face that helps keep the sun-heated water inside the copper coils warm. There’s an inlet and outlet pipe to draw water into and out of the solar water heating panels.
This solar hot water collector is the most commonly used in the united states.