Solar Water Heaters / Solar Geysers

Upon reviewing the full range of solar water heater technologies available, PDC Solar approached Professor Keith Palmer of Stellenbosch University for assistance in identifying the best product available. Solar heat pipes (Figure 1 and Figure 2) were identified as the most efficient technology for heating water and are offered at the most competitive prices when compared to the more conventional solar panel (Figure 3). Further research found NuPower delivering the appliances in Cape Town and with a distribution network in Gauteng.

Solar Water Heater
Figure 1: The solar heat pipes, holding tank and tank cover

One of the most exciting advances in the NuPower technology stable is the ability to pre-heat households’ water, using the solar heat pipes, and circulates the hot water into and through an existing electrical geyser. By using a small photovoltaic panel that drives a 12v pump (therefore only energized during the day) and setting the power on by means thermostat placed in the solar heated manifold, it is possible to ensure that the solar water is always hotter than the geyser setting (also controlled by a thermostat). In this way, when the sun shines it keeps the geyser in hot water at no cost. When the sun does not shine and a significant amount of water is drawn from the geyser, the electrical element will heat the water.

Solar Water Heater
Figure 2: High pressure split system

After a number of meetings PDC Solar has been offered a distribution agreement from ITAS Services (Pty) Ltd (trading as NuPower) for both the Western Cape and Gauteng. This ties PDC Solar to installing NuPower’s technology. However, given that the cost of the appliance in within the bottom third of all solar water heaters and the performance in the top one third, this is considered an advantage.

Solar Water Heater
Figure 3: The more conventional solar panel and header tank

For information relating to solar geyser solutions see:

PDC Solar Geysers
Susman Avenue, Blairgowrie
Johannesburg, Gauteng
South Africa
Phone: +27 (0)11 886 4661