ABOUT US

In today’s uncertain economic climate there isn’t much we can be certain of in the future. The things we can however be certain of, is the fact that Eskom is having serious problems in supplying electricity, and is likely to be a problem for the foreseeable future. The price of electricity to the consumer is likely to increase substantially over the next five years. The next thing we can be certain of, and according to the new law that domestic consumers using more than 500Kw per month will pay extra for electricity on a sliding scale. We can also be certain that the environment is being severely impacted by the insatiable demand for energy across the world.

EcoSmart is committed to a Green World and therefore specialize in providing Energy Efficient solutions to the domestic and commercial markets by utilising Renewable Energy.

Solar Hot Water Systems

How does a solar hot water system work?

A solar hot water system consists of a solar collector to harness the suns’ solar radiant energy. The solar collector may be a flat plate collector or one of several types of vacuum tube collectors.

Flat plate collectors are less expensive than vacuum tube collectors but normally are less effective.

This suns’ energy is used to heat the water in the solar collector which is then circulates by thermo syphon or circulating pump to a storage tank or solar geyser. There are two different types of solar water systems available.

Thermo syphon systems

A Thermo syphon system consists of a solar collector which is situated on the roof preferably facing north at a preferred angle perpendicular (90 degrees) to the sun’s rays. The solar geyser is placed or mounted above the solar collector. The water within the solar collector is heated by the sun radiant heat which in turn rises to the geyser. The geyser has two connections, one for the hot water which is rising from the collector and another connection for the cold water from the geyser to the solar collector which is then heated and rises via the first connection.

Split Pumped Systems

A split pumped system consists of a solar collector which is placed or mounted on the roof, facing as close as possible to north and preferably at an angle perpendicular to the sun’s rays. The pumped system has a circulating pump which is activated by a solar controller which has temperature sensors connected to the solar collector and to the bottom of the geyser. The pump is activated when the temperature difference rises between the solar collector and the geyser temperature, normally by 8 to 15 degrees Celsius. The circulating pump is then stopped when the temperature difference between the solar collector and the geyser has reduced, normally between 2 and 4 degrees Celsius.

Eskom approved Systems offered by EcoSmart™

Components of the Solar Hot Water Systems used by EcoSmart™

• EcoTherm Solartherm Geysers
  
  • The EcoTherm Solartherm Geysers are the best solar geysers available in the world today (Best under the Sun) guaranteed for 10 years and the only non-maintenance geyser available in South Africa. The geysers have a PEX (Polyethylene cross fibre) lining which cannot corrode, and can be used with any type of water effectively without the requirement of an artificial anode as is custom with all other type manufactured geysers.
• Solar Collectors
  
  • Flat Plate Collectors
    
  • Vacuum Tube Collectors
    EcoSmart™ are agents for various Flat Plate and Vacuum Tube Collectors, including collectors manufactured in Germany.
• Circulating Pumps
  
  • Grundfos Brass
    
  • Wilo Brass
    
  • EcoSmart™ have tested most pumps currently available and use what we consider is the best in the world. EcoSmart™ only use the brass version of these pumps
• Solar Controllers
  
  • SRC868C6/SRC868CQ
    
  • Geyserwise
    
  • EcoSmart™ use the controllers above firstly as they have a holiday function available which is imperative in South African conditions. The SRC868 controllers also have the added function of regulating a ring feed pump which is used to circulate hot water via a hot water ring feed which allows instant hot water at any hot water outlet in a home.
• Air/Steam Release Valve
  
  • EcoSmart™ after extensive testing only use the Caleffi Air/Steam release valves. These valves are essential in a pumped solar installation to protect the solar equipment when high temperatures are reached
• Copper Piping and fittings
  
  • EcoSmart™ only use class 1 copper tubing which allow the use of compression fittings and due to high temperatures give a much longer life expectancy
• Pipe Insulation
  
  • EcoSmart™ use UV protected pipe insulation with extra thick sides for minimum heat loss as well as protection for freezing conditions
    

Frequently Asked Questions

Why face collector north

In the southern hemisphere the sun’s energy is at its highest at midday facing north.
The sun’s energy gradually increases during the day to its highest level at midday and then gradually reduces.

What angle should the collector be mounted

The most energy is harvested from the sun when the collector is placed perpendicular (90 degrees) to the sun.
The angle of the collector is dependent on the energy required during the different seasons.
The angle will vary according to the seasons and the latitude of the area. The best angle should be used for winter conditions.

When to use flat plate collectors

Flat Plate Collectors generally are less effective and should therefore be used in areas with high sun irradiation levels.
Flat Plate Collectors should generally not be used near the coast. (see Interesting facts)

When to use vacuum tube collectors

Vacuum Tube Collectors should advisably be used near the coast.

How long will the system last

The system consists of different components which have different Warrantees or Guarantees.
EcoSmart™ only use EcoTherm Solartherm Geysers which have a 10 Year Guarantee and a life expectancy in excess of 50 years. (Best under the Sun)
The solar collectors have a warrantee of 10 years with a life expectancy far beyond.
The system will deteriorate faster if excess temperatures are not prevented normally caused by power failures causing circulation to stop.
We expect pumps to last for 15 Years although they have a 1 year warrantee.

How much electricity will I save

This is totally dependent on various factors such as

Summer or winter conditions
Storage tank or geyser capacity
Water usage at night as well as usage during early morning

Why use brass pumps

The pumps used is largely dependent on the quality of the water. EcoSmart™ used cast iron pumps in the past but had to replace the pumps on average within 1 year due to total corrosion caused by the deterioration of water.
EcoSmart™ now only use brass or stainless steel pumps

Interesting Information from EcoSmart™

Flat Plate collectors are not ideal for use near the coast for two main reasons. The first reason is that the solar irradiation levels are much lower at the coast than internally. The Vacuum Tubes are more efficient and therefore more appropriate near the coast.
Flat Plate Collectors are not totally sealed and allow air behind the glass panel which in turn is heated in the morning causing the moisture in the air to condensate against the glass panel. The flat plat collectors normally have weep holes for the condensation to escape. The minute salt particles in the condensation attaches itself to the glass and build up over the years. The salt deposits eventually cause reflection of the sun’s irradiation which in turn causes the flat plat panel to become less effective. This obviously leads to less and less electrical savings being achieved with the panels.
Vacuum Tube Collectors are extremely efficient and should be sized correctly to the amount of water being heated. The solar irradiation difference between summer and winter is huge. The example blow illustrates the solar irradiation levels for Cape Town with panels being placed horizontally compared to optimal summer at 19 degrees and optimal winter at 49 degrees.

We are able to deduce the following from the bar chart above.

A 200 Litre geyser with a 4kW electrical element will take 2 hours 20 minutes to heat the water from 15 degrees Celsius to 55 degrees Celsius. Assuming that electricity costs R1.35 per kWh, the total electrical consumption will be approximately 9.33 kWh which equates to R12.60 excluding standing losses, electrical losses etc.

A 200 litre geyser heated by 2 square meters of solar collectors in June with the panels placed horizontally will save the equivalent of R7.05 for the day and will only be able to heat the water from 15 degrees Celsius to about 37 degrees Celsius.

A 200 litre geyser heated by 2 square meters of solar collectors in January with the panels placed horizontally will save the equivalent of R21.35 for the day and will heat the water from 15 degrees Celsius to about 78 degrees Celsius.