Solar Water Heater System

Solar water heaters, sometimes called solar domestic hot water systems can be a cost-effective way to generate hot water for your home. They can be used in any shadow-free areas, and the fuel they use sunshine is free.

Working Of a Solar Water Heater

The Sun’s rays fall on the collector panel (a component of solar water heating system). A black absorbing surface (absorber) inside the collectors absorbs solar radiation and transfers the heat energy to water flowing through it. Heated water is collected in a tank which is insulated to prevent heat loss. Circulation of water from the tank through the collectors and back to the tank continues automatically due to thermo siphon system. Based on the collector system, solar water heaters can be of two types: A solar water heater consists of a collector to collect solar energy and an insulated storage tank to store hot water. The stored hot water can be used later any time.

Types Of Solar Water Heater

Basically two types of solar water heater are available in the market

Flat Plate Collector (FPC) Solar Water Heater

Flat Plate solar water heater – Solar radiation is absorbed by flat plate collectors which consist of an insulated outer metallic box covered on the top with glass sheet.

A black absorbing surface (absorber) inside the flat plate collectors absorbs solar radiation and transfers the energy to water flowing through it.

Evacuated Tube Collector (ETC) Based Solar Water Heater

Evacuated Tube Collector – The Collector is made of double layer borosilicate glass tubes evacuated for providing insulation.

An ETC collector is made of double layer borosilicate glass tubes evacuated for providing insulation. The outer wall of the inner tube is coated with selective absorbing material. This helps absorption of solar radiation and transfers the heat to the water which flows through the inner tube.