Flat plate solar water heating system

Flat-plate collectors capture the energy from the sun. There are different designs,
but for the most part they use heat transfer fluid. Once cold water has been
collected in the storage tank, the flat-plate collector starts looping the fluid
through the cold water and heats it up.
But this only happens after the radiation energy has been transformed into thermal
energy through the collector. After the fluid has been heated it will start to
circulate. The collector plate consists of a copper sheet and tubing. The surface is
coated with a dark material, specifically to increase absorbency efficiency.
The collector is also very well insulated in order to prevent heat from escaping.