Standard Bank invested in a hybrid solar water heating and heat pump system at the company’s head office in Johannesburg, as it moves to increase energy efficiency and reduce its carbon footprint.
The new R2.3-million system, installed by Kayema Energy Solutions, is expected to save nearly R1-million a year in energy costs, thus a return on investment would be seen in just under 4 years.
The 400-kW hybrid system consists of 100 solar water heater collectors, which will heat about 20 000 l of water, while another 28 000 l of water is heated using energy efficient heat pumps.
It reduces the building’s energy consumption by 5%, and Standard Bank noted that the energy saving was equivalent to powering seven households for a year.
The 100-collector installation, which took about four months to design and install, covers over 200 m2 on the roof of 6 Simmonds street in central Johannesburg. A back-up and top-up system consisting of two heat pumps supports the solar installation for days when the sunshine is not optimal.
The solar collectors were specifically chosen as they make use of a black chrome absorber, which performs better than painted collectors, and ensures a longer life-span of the panels.
There is an ultrasonic weld between the absorber thins and the copper pipes, which allows more efficient heat transfer.
The installation consists of some 700 m of copper piping.
The 4 mm tempered glass used in the panels is hail resistant, and has a low metal content, which also allows for better heat absorbency.
