Passive Solar Water Heaters

Posted by admin on Jan 11, 2014 in Posts

Passive Solar Water Heaters – How are they different from Active Solar Water heaters?

Looking at the present scenario, Energy uses have risen tremendously in the last few decades which in turn have made it much costlier in the long run. The savings keep on reducing while the number electrical appliances in homes are on a rise; in this situation going for solar water heater can prove to be an excellent choice for cost cutting and sustainability.

Solar water heater can be broadly classified into two different types: Active and Passive. They both depend upon the sun’s energy, but they have differences in their working mechanisms. This article will explain all about passive solar heaters and why it is a cost effective way to water heating solutions. The two basic parts of a solar heater are an insulated water storage tank and a solar collector. The solar collector is the one which heats the water and move it up into the tank. The storage tank is similar in design to a tank type electric heater and performs almost the same functions. A drawback of a passive system is its lesser efficiency, but it is more durable, reliable and when compared is less costly than an active one.

They are generally available in two different varieties, one the integral collector storage (ICS) and the other thermo siphon system.
The ICS system has the storage tank situated below the solar collector, in which the cold water flows, gets heated and then transferred to the storage tank for use. This is suited for tropical or hot weather climate where temperatures never touch freezing point; moreover this water heater is practical for daytime and evening use.

The thermo siphon is a bit different than the ICS system as it keeps the storage tank above the solar collector tubes and relies on natural physics that hot water being less dense rises up and cold water sinks. The cold water leaves the base of the tank and moves into the tubes where it gets heated and rises up into the storage tank. It is suited for moderate climates and also for day and night use.

Solar heaters are a very reliable and economical source of hot water, but they also rely on the Sun for their working. On days when it is way too cloudy or additional amount of hot water is required, calls for a backup heater.