An aerial view of the Senwes Head Office building, in Klerksdorp, gives the impression of a solar energy plant.
All the roofs of the Senwes buildings and carports are covered with 2 392 solar panels with a total capacity of 753.48kWp. The total projected solar utilisation per annum is 1 173 913 kWh, which constitutes 39% of the total electricity consumption at Senwes head office and will result in a cost saving of R2 million in the first year.
Joe Maswanganyi, Group Executive Director of Senwes said: “In line with our sustainability objectives and, inter alia, our contribution to reducing the carbon footprint, the Solar PV will save approximately 1kg CO2/kWh. The projected carbon savings will amount to 1172 tonnes CO2 per annum, equivalent to 270 running cars or 481 tons of coal per annum”.
This project commenced in January this year and was completed in June, when it was integrated into the existing electricity grid. The project manager, Johan le Roux, monitors the Solar PV with a special App, Sunny Portal, which gives you the total kWh produced per hour at a glimpse. He is very excited about the results yielded thus far – a total of approximately 70 000 kWh, which amounts to R117 600, was saved over a one month period.
In its endeavours to become a complete green building, Senwes replaced the old air conditioners with an HVAC VRV air conditioning system in 2009 and it has yielded a saving of 23% already. Another project was the replacement of all the old conventional light tubes with new motion-detection LED lighting, which will result in a 45% reduction in the current lighting-based electricity consumption.
The energy efficiency in commercial buildings according to the South African National Standard (SANS 204) for Climatic Zone 1 is 200kWh/m2. Senwes improved its energy efficiency from 228,43 kWh/m2 to 143kWh/m2. All the above-mentioned projects equate to a carbon saving of nearly 23 440 tonnes and a cost saving of approximately R47 million over a 20-year period.
