Solar Water Heater

Solar water heater use the sun energy to heat water during the day. This hot water is stored inside an insulated solar hot water tank for use whenever required. The sun rays have enough energy to heat water up to 55°C to 70°C which is more than sufficient for bathing and washing purpose in bathrooms and kitchen.

With no maintenance requirement, solar heater provides a low cost long term solution to getting hot water. For cloudy days, solar water heater have a inbuilt electric heating element for backup. Basically, solar water heater do conversion of sunlight into renewable energy for water heating using a solar thermal collector.

Solar water heater comes in two major technologies - FPC solar water heater and ETC solar water heater.

ETC Solar Water Heater

Evacuated Tube Collector (ETC) acts as an absorber in the solar water heater. Each evacuated tube consists of two glass tubes having vacuum in between which is an excellent insulator.

The incident solar radiation falling on the tube passes through the outer transparent tube and strikes the outer of inner tube. It absorbs heat energy and then passes to the cold water flowing in the tube. An evacuated tube technology based solar water heating system is most energy efficient and cost effective that are best suitable for home use.

FPC Solar Water Heater

In FPC solar water heater, the solar radiation is absorbed by Flat Plate Collectors (FPC) which consist of an insulated outer metallic box covered on the top with glass sheet. Inside there are blackened metallic absorber (selectively coated) sheets with built in channels or riser tubes to carry water. The absorber absorbs the solar radiation and transfers the heat to the flowing water. A Flat Plate technology based solar water heater is most energy efficient and long life. Suitable for home use.

Pressurized and Heat-Exchanger

Basically there only 2 types of solar system. In few areas water quality is very poor, heat-exchanger type solar system is recommended.

If the pressure pump is used to feed the bathrooms or utility, pressurized water heater is recommended.

If above mentioned both conditions are applied, pressurized with heat-exchanger solar water heater is recommended.