Solar water heaters save money because the fuel source, the sun, cost nothing. It is the means of storing the energy from the sun that is expensive. Although there still will be need for some other back up heat source such as electricity or gas, the use of solar heater will reduce the use of these considerably; if of course you live in a warmer climate your solar water heater will be more beneficial because there will be more sun shining. Too, in warmer climates, installation and the types of system needed may be less expensive.
Solar energy is a clean source of energy and is environmentally friendly and will not leave any left over side effects from its use as fossil fuel do. The initial cost and the weather are the prohibitive reason these are not widely used in colder areas. At present to install “an active flat plate solar collector system will cost you from $2,500 to $3,500 dollars; a passive system can be installed from about $1,000 to $2,000. This will create about 80 to 100 gallons of hot water daily.”
Solar hot water heaters are of two types, active and passive. Both need storage tanks but they differ in the mechanical means of supplying the necessary hot water. In active solar systems there are direct and indirect circulation systems: In the direct, its as it says, attached pumps collects hot water directly into the home. These are to be used only in warm climates with no freezing temperatures. In the indirect active systems the mechanism is different since these must assure that the water does not freeze. These are the choice for colder climates.
In the less expensive passive systems there are also two system types: In warmer climates the integral collector-storage and the thermosyphon system. These are different in that collector is installed below the storage tank. This is so because as the water warms it rises. In this case it rises and flows into the storage tank above. It is heavy system and will not be suitable for lightweight roofs. It is often more expensive of the two types of passive systems.
In addition to the solar water heating systems there is need for an additional means of energy when there is no sun. Conventional water heaters help out here. They are an added on expense or they may be included with the purchases system.
Another benefit from solar systems, especially the passive types, is that they are pretty much maintenance free; the active types require about the same care as the standard water heater. The biggest benefit of solar energy in general is that it is a pure source of energy and there will be no harmful after effects to the environment.
I predict great things not only for solar water heating but solar energy in general. There is much on-going research and the installation price of the solar panes are becoming reasonable. We simply will have to watch and wait.