SOLAR GEYSERS

It is estimated that depending on usage, electric geysers may account for as much as 20% of the average household electricity bill. 

There are two types of high pressure systems available namely the ‘split’ and ‘thermo-siphon’.

Split systems are suitable for use in urban areas where aesthetics are important. Only the vacuum tube collectors are mounted on the roof with the hot water tank placed inside the roof, the same as conventional geysers. A special circulation pump is fitted to circulate water from the internal geyser through the collectors where it is heated by the sun. This super reliable pump has no brushes or bearings to wear, and will assure a lifetime of reliable operation.

Thermo-siphon geysers are mounted on top of roof tiles or thatch. Because the geyser is mounted directly above the collectors it eliminates the need for a circulation pump, making the Thermo-siphon geyser a cheaper option. Geyser size determines the number of collectors per geyser.

Retro fitting is made possible by converting an existing geyser for solar operation by fitting a special injecting nozzle to the geyser.

Existing geyser can be retro-fitted providing the geyser is less than 5 years old.

High-pressure Split system:

These units are intended for use in town and cities with their primary aim to save the user on electricity.

Only the solar collector is mounted on the roof and the heated water is circulated to an internal water cylinder that stores the heated water.

An electrical element is also fitted to heat the water in the absence of sunlight during cloudy days. These units are much more suited for neat city housing where the primary function is to save electricity. 

Low-pressure units:

Low pressure units are best suited for rural areas where the water pressure is below 1.3bar and usually fed via an elevated water tank.

Typical installation is on the roof of a building and hot water gravitates from the tank to the hot water taps

Tank Capacity:

80Lt (100Lt if the water in the collectors is included)

Designing and sizing a system is especially important in areas where no electricity is available

The vacuum tubes are filled with water from the tank and heated by the sun. As the water in the tubes warms, it rises and mixes with the cold water from the tank, eventually heating all the water to a high temperature. This natural phenomenon is called the thermo-siphon effect. As the pressure inside the tank is equal to that in the glass tubes, the maximum pressure is limited to 0.3bar and the units are usually used in conjunction with a manual filling tap or a variable pressure regulator to limit the pressure in the system. These systems are very effective and ideal for farms, low-cost housing.