Solar Hot Water System - Relying on the Old Clean Sun

Wouldn't it be great if there were some fairly easy way to reduce your electric bills? This is possible simply by installing a solar power hot water system.
These units rely on the natural heat from the sun in order to help heat water, thereby reducing your dependence on more conventional means which relies on electricity to heat up coils which then heat the water.
With solar hot water systems there will be some form of storage tank and collector.
The storage tank(s) hold the actual water supply while the collectors are for gathering the sun's heat.
There are basically two types of systems: active and passive.
Active have a series of pumps and controls which actively heat up the sun while passive do not have any of the elements and tend to rely much more heavily on the sun's heat in order to make water heat up.
Collectors are a major element of the solar hot water system and there are three types generally found in most units: flat-plat, integral, and evacuated tube.
Flat-plate collectors are boxes which have been insulated and weather proofed with some sort of glass or plastic cover.
Integral collector storage (ICS) systems are those black tubes that can be seen on the roofs of many homes.
Cold water first passes through the collectors to preheat the water.
This form of collector is most often teamed with a conventional water heater.
Finally there are the evacuated tube collectors which are rows of glass tubes.
The tubes are lined up and covered with a coating to absorb energy but prevent heat loss.
One type of active solar unit is a direct circulation system.
These units are found most often in warmer climates where freezing weather isn't an issue.
In this system the water is moved through collectors and then into the home for use.
The other type is the indirect unit where the water goes from the collectors to a heat exchanger and then into the house.
There are also a couple of passive solar hot water systems available: integral-collector and thermosysphon systems.
Thermosyphon systems work on the principal that heat raises while cold sinks.
This principal works with water as well as air.
In the thermosyphon system, the collector is installed below the tank so that the hot water will rise to the top enabling the cooler water to be siphoned from the bottom.
While most solar units do currently have to be teamed with a conventional water heater to ensure there's a constant steady stream of hot (and cold) water available, as technology improves this will cease to be the case and a number of solar hot water systems which do not have a conventional backup water heater are being tested.
The important issue is that man is seeking ways to reduce and in some cases, eliminate his dependence upon conventional energy and is looking for cleaner, more efficient means of meeting energy demands.