Solar water heaters facts

Posted by admin on Jan 9, 2014 in Posts

Solar water heater is equipment which facilitates us by providing hot water for various purposes by using the energy from the sun. To make water hot by using solar energy, there are many new innovative ideas and renewable energy technologies that are well built since many years.

Solar water heating (SWH) systems comprise of solar collector and storage tanks in which the process of water heating by using solar energy is done. Mainly there are two different types of solar water heating (SWH) systems: active and passive. Active systems comprise of circulating pumps and controls but passive is not provided with any pumps. Active solar water heating systems are more efficient as compared to Passive solar water heating systems and hence are little more expensive than Passive solar water heating systems. Passive solar water heating systems are typically less expensive than active systems, but they’re usually not as efficient. Nonetheless passive systems are more reliable that active systems and they work for a long duration of time.

The main motive of solar water heating systems is making warm water available for most of the year. Even on cloudy days it is possible to get warm water as the water gets heated because of the diffused radiation which is available in the air. But during winters as the intensity of heat is less therefore sufficient hot water may not be delivered during that season. It does not make any such difference as the water which is coming from the system is stored in geyser which has an electric back up by which we can avail hot water whenever we switch on the power supply. If no geyser is present at home then the electric backup will be provided in the storage tank itself.

SWH systems provide many facilities and helps in using less non-renewable resources. Once it is installed in anybody’s home then there is hardly any cost for getting hot water as it heats up the water with the help of natural source. This system also helps in reducing carbon dioxide emissions when it is installed as it is a renewable source of heating. Even the maintenance cost of SWH system is very less. The solar water heating systems come with a warranty of five years or ten years and if anything happens to the system then it will be made proper without any charge. If the systems are under well maintained condition then the pumps are capable to operate for more than ten years.

To make solar water heater working there has to be a collector which should be located in the roof of the building or the ceiling facing the sun. The job of the collector is to heat the water which is flowing in the system and then the hot water is either pumped (active) or is flown naturally (passive) through it. The collector is manufactured with the help of glass topped insulated box which is having a flat solar absorber which is made up of sheet metal. These are attached to copper heat exchanger pipes or a set of metal tubes which is covered by a vacuum glass cylinder.

The solar collectors were present in the United States during 1900. At that time the system consisted of a black-painted tank which was kept on a roof. In 1896 Clarence Kemp of Baltimore of USA had an idea and closed the tank inside a wooden box which gave us our first ‘batch water heater’ as we know it today.

Two major issues should be kept in mind while designing any solar water heaters. These are: freeze protection and overheat protection. Freeze protection helps to prevent any sort of destruction of the water system which happens because of the extension of freezing transfer fluid. With the help of Drain back systems it is possible to drain the transferred fluid from the system when the pump is not under operation. The problem can also be overcome by using antifreeze in the heat transfer fluid which is used by various indirect systems. It also helps to keep the water temperature at a moderate heat level even after the hot water is not used for more than two or three days.

The price of a home solar water heating systems is very cheap and affordable by everyone which varies from $1,500 to $3,500. With this type of investment a lot more money for hot water can be saved and it is very promising in today’s rising energy cost.