Solar Water Heating

Solar Water Heating is a method of heating water using panels fitted outdoors to harness heat from the sun, and then storing this heated water in a storage tank. The methods of generating solar heated water is categorised into two heat transfer types, namely Direct (used in frost-free/coastal regions in S.A) and In-Direct (used in frost-prone/inland regions in S.A).

Each of these heat transfer types can be further categorised by circulation type, namely Thermosiphon systems (natural flow of water between panel and an elevated geyser), and Pumped systems (pump operated by controller, with geyser in any location).

Any size geyser may be used for solar; however we will always align the storage capacity and panel surface area to suit the homes water heating requirements, as well as to gain the most from the available sun throughout the day.

If an existing electric geyser is in place and is in good working condition, the first offer would be to convert it to solar (termed “Retrofit”), in a pumped system, allowing the geyser to remain in its current location and reducing our clients initial capital layout. If a new geyser is needed, a pumped or thermosiphon system may be offered, using a solar

When offering a thermosiphon system we would always consider the number of users, as during summer seasons, if the hot water is not used, the water continues to heat until the Solar T/P (temperature/pressure) valve opens @ ±97°C to dissipate the excess heat. In a pumped system, this is controlled by the system controller to limit the water temperature in the geyser to 80°C, reducing strain and increasing the lifespan of the system.

For both high pressure thermosiphon and pumped systems, there are two main types of panels used, being either flat plate solar collectors or evacuated tube collectors. Either of these collectors have conditions that need to be assessed prior to being applied.

Besides supplying and installing for the residential sector, SolarJoy has installed Solar Water Heating systems for apartment blocks as well with uniquely innovated designs which include sophisticated PLC controllers (an Industrial Programmable controller) to have increased overall system efficiency with reduced components and materials.

SolarJoy has also compiled detailed energy audits, re-routed and insulated hot water lines for institutions in the medical sectors, reducing water heating costs by up to 50%.

Currently SolarJoy imports, Flat Plate Solar Panels, circulation pumps and solenoid valves, and combine these with local products and equipment to supply SABS approved Solar Water Heating systems to our clients. In addition we buy wholly or partially local products from other companies in the industry and provide these products to our clients.

Although the numbers of products are limited, we configure these in multiple systems to offer very efficient assemblies with lower cost to clients for better performance.

Solar Water Heating Simplified
For many, finding the correct solar water heating system to match their intended application is often misdirected by a number of factors.
For our clients to understand how solar water heating works and in turn knowing that their system was the correct system applied, is a key factor in our service.
Here is a simple breakdown of the selection process of a system:

This system shows a typical pumped solar water heating system. Sun heats the panel, cold water entering at the bottom, warms up and rises to the top of the panel, controller gets the signal that’s water is warm enough, pump switches on, water pumped to geyser, fresh cooler water pumps into panel, you open the tap and you’ve got FREE hot water.

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