11 July 2012 – Manufacturer of lead acid batteries in South Africa, First National Battery (FNB), a subsidiary of JSE listed Metair Investments Limited, assisted with the installation of a solar water treatment station in the OR Tambo district municipality community of Mnxehazi, situated between Ntabankulu and Mount Frere in the Eastern Cape.
Before the installation, the village’s 1,596 people had no access to running water and travelled 6.0 km to the Umzimvubu River, South Africa’s third largest river, to collect water for their daily requirements. The ministry of water affairs became aware of the villagers’ plight and tasked the Development of Sustainable Technologies and the Council for Scientific Research respectively to find a solution to the problem. As the village is surrounded by mountains and has no access to electricity, solar energy was recommended for this site.
The complete solar system – that is, the 40 solar panels, charge controllers, inverters and 12 batteries – was supplied by FNB. The batteries used are the M-Solar deep cycle batteries manufactured by FNB in East London, and widely used in most solar applications in South Africa and in other countries, including Australia. The reason for selecting the M-Solar batteries is that these batteries last longer and require minimal maintenance. The power supply from the batteries is inverted to 220 volts to power the water treatment works.
Raw water is pumped from the Umzimvubu River into the water treatment works by submersible pumps (one duty and one standby). The water treatment system consists of three sets of dosing pumps (each containing a duty and a standby pump), a settling tank, a 5,000 litre balancing tank, and two sand filters. The clear water is stored in two 10,000 litre storage tanks, from where it is pumped by booster pumps to the reservoir at the village.
A total of 34,000 litres of water is pumped to the reservoir per day. It is then gravity fed to the village at various points. Each person receives 18 litres per day. The solar and water treatment systems are fully automatic. Only backwashing of the sand filters has to be done manually.