Flat Plate Solar Water Heater Installation

   For most residential and small commercial hot water applications, the solar flat plate collector tends to be more cost effective due to their simple design, low cost, and relatively easier installation compared to other forms of hot water heating systems. Also, solar flat plate collectors are more than capable of delivering the necessary quantity of hot water at the required temperature.

   A large heat-absorbing plate, typically made of copper or aluminum because both are good heat conductors, is painted or chemically etched black to absorb as much solar radiation as possible for maximum efficiency in a solar flat plate collector.

   The heat transfer fluid, typically water, is contained in several parallel copper pipes or tubes known as risers that run lengthways across the blackened heat-absorbing surface.

  To assure 1maximum surface contact and heat transport,  these copper pipes are directly  brazed,  soldered, or bonded to the  absorber  plate. The temperature of the absorbing surface rises as a  effect of sunlight heating it. The fluid flowing through the copper pipes, which are then used by the household, absorbs the heat  generated as the plate heats up.

   An insulated metal or wooden box with a sheet of  glazing material- glass or plastic- on the front protects the pipes and absorber plate and generates  an insulating air space. The majority  of the incoming radiation is picked up  by the blackened absorber because this glazing material does not significantly  absorb the sun's thermal energy.

  This heat is trapped in the air space between the plate and glazing material, preventing it from reentering the atmosphere. The fluid inside the collector receives heat from the absorber plate as it warms up, but its surroundings also lose heat. A flat plate collector's bottom and sides are insulated with high temperature rigid foam or aluminum foil insulation, as shown, to reduce this heat loss.

   Flat plate collectors can heat the fluid inside using either direct or indirect sunlight from a wide range of different angles. They also function in diffused light, which is dominant on cloudy days as it is the surrounding heat that is being absorbed and not the light, unlike photovoltaic cells. How hot the circulating water gets will depend mostly on the time of the year, how clear the skies are and how slowly the water flows through the collectors pipes.