Zero Is The New Black

Solar water heaters very well qualifies for DIY project but before you start there are some basic facts that you should know . These will help in correctly identifing your requirments and selecting right solar water heater to make .

How does it work ?

Solar water heaters use the sun light to heat water in a collector and heated water is then stored in a storage tank for use. Depending on the requirements this heated water can be used to feed in to conventional water heater which has to spend little or no energy to heat it further.

Types of Solar Water Heater

There are two types of Solar water heaters - active or passive ,  active systems being the most common one .

Active solar water heaters rely on active components like electric pumps to circulate water, or other heat-transfer fluids through the collectors.

These are the three types of active solar water-heating systems:

Direct-circulation systems use pumps to circulate clean water directly through the collectors and is appropriate for the areas that  do not freeze for long periods and do not have hard/acidic water Indirect-circulation systems use pumps to  circulate heat transfer fluids through collectors and heat is transferred to water through heat exchangers .

Passive solar water heaters depends on gravity and natural circulation of hot water. No electrical components are used and hence these are more reliable .
The two most popular types of passive systems are:

Integral-collector storage systems with  storage tanks placed in an insulated box and glazed side facing the sun. These solar collectors are suited for areas where temperatures doesn't  go below freezing point and hot water needs are in daytime/evenings. They loses temperature overnight so not very much suited for early morning needs . Thermo Syphon systems systems rely on the natural convection of warm water. As water in the solar collector heats it becomes lighter and rises naturally into the tank above due to convection and cold water flows down the   to the collector, enhancing the circulation. Some manufacturers place the storage tank in the house's attic, concealing it from view.

Build or Buy ?
Commercially available  Solar water heater Kits or complete system  may be very costly but you can easily make one using a DIY guide and locally available parts  for  less than $70 !