Solar Water Heating Systems


Solar Water Heating System (SHWS) is a popular device that harnesses the solar energy for our needs. The choice of system depends on heat requirement, weather conditions, heat transfer fluid quality, space availability, annual solar radiation, etc. The SHW systems are economical, pollution free and easy for operation in warm countries like ours. Evacuated Tube Collectors (ETC) based Solar Water Heaters Evacuated Tube Collector is made of tripal 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. Wide spread utilization of solar water heaters can reduce a significant portion of the conventional energy being used for heating water in homes, factories and other commercial and institutional establishments. Salient Features of Solar Water Heating System Solar Hot Water System turns…

Solar Water Heating System (SHWS) is a popular device that harnesses the solar energy for our needs.

The choice of system depends on heat requirement, weather conditions, heat transfer fluid quality, space availability, annual solar radiation, etc. The SHW systems are economical, pollution free and easy for operation in warm countries like ours.

Evacuated Tube Collectors (ETC) based Solar Water Heaters

Evacuated Tube Collector is made of tripal 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.

Wide spread utilization of solar water heaters can reduce a significant portion of the conventional energy being used for heating water in homes, factories and other commercial and institutional establishments.

Salient Features of Solar Water Heating System

Solar Hot Water System turns cold water into hot water with the help of sun’s rays.

  • Around 60 deg. – 80 deg. C temperature can be attained depending on solar radiation, weather conditions and solar collector system efficiency
  • Hot water for homes, hostels, hotels, hospitals, restaurants, dairies, industries etc.
  • Can be installed on roof-tops, building terrace and open ground where there is no shading, south orientation of collectors and over-head tank above SWH system
  • SWH system generates hot water on clear sunny days (maximum), partially clouded (moderate) but not in rainy or heavy overcast day
  • Only soft and potable water can be used
  • Stainless Steel is used for small tanks whereas Mild Steel tanks with anticorrosion coating inside are used for large tanks
  • Solar water heaters of 100-500 litres capacity are suited for domestic application.
  • Larger systems can be used in restaurants, guest houses, hotels, hospitals, industries etc.

Benefits:

A 100 litres capacity SWH can replace an electric geyser for residential use and saves 1500 units of electricity annually.

A SWH of 100 litres capacity can prevent emission of 1.5 tonnes of carbondioxide per year.

Life: 15-20 years

Payback period:

Though the initial investment for a solar water heater is high compared to available conventional alternatives, the return on investment has become increasingly attractive with the increase in prices of conventional energy. The payback period depends on the site of installation, utilization pattern and fuel replaced. The period is around 2 years when electricity is replaced.