The absorption layer

The absorption layer on solar collectors is a critical part of the device, which ensures efficient absorption of solar radiation and its conversion into heat. This layer is placed on the surface of the collector and is made of a material capable of quickly heating up and transferring heat to a heat-carrying medium (often water or antifreeze solution). The absorption layer is usually dark or black because these colors have a high ability to absorb light energy.

The main tasks of the absorbent layer are:

Absorption of solar radiation: The material from which the absorbent layer is made must have the ability to effectively absorb solar radiation and convert it into heat.

Minimal heat loss: The absorption layer should minimize heat loss to maximize the efficiency of solar heat recovery.

Fast conversion of light radiation into heat: The material of the absorption layer should be able to heat up quickly, which allows heat to be efficiently transferred to the heat-carrying medium.

The material used for the production of the absorption layer can be different and depends on the specific type of solar collector. Some of the commonly used materials include:

Copper: It is mainly used in solar collectors of the copper pipe type. Honey has a high thermal conductivity and is able to efficiently transfer heat to a heat-carrying medium.
Aluminum: Aluminum absorption layers are used in solar collectors for higher temperatures. Aluminum has good corrosion resistance.
Selective coatings: These coatings are composed of multiple layers of different materials and have the ability to selectively absorb light and emit minimal heat. This increases the efficiency of the collector.
The absorption layer is the key element that allows solar collectors to convert the sun's energy into heat, which is then used to heat hot water or to support heating.
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