One of the three lighthouses along the Northern Cape coastline marked 35 years of service in November.
The Groenriviermond lighthouse is situated 80 km from the inland town of Garies, while the other two lighthouses on the Northern Cape coastline are at Port Nolloth and Hondeklipbaai.
The one at Groenriviermond is one of only two South African lighthouses to have a yellow tower. The 17,2 m cylindrical concrete tower is painted yellow with a black band and has a yellow lantern house. The other one with a yellow tower is at Cape Vidal along the KwaZulu-Natal coast.
The lighthouse is not connected to the main electricity supply and uses solar technology as the primary source of power. Photovoltaic (PV) panels convert sunlight into electrical energy, which is stored in batteries and used to power the lighthouse at night. Before the installation of solar technology, the lighthouse was powered by diesel generators that ran 24 hours a day, seven days a week.
The lighthouse still has one diesel generator on site, used as back-up.
It is fully automated and is not manned. Scheduled maintenance is carried out by teams from Transnet National Ports Authority (TNPA) in Port Nolloth and Cape Town.
Teams can spend up to a week at the station, checking and servicing the light, the solar system, and the standby engine. The change to solar has reduced the amount of fuel that must be purchased, transported to and stored on site, which in turn has reduced the environmental and safety risks, and associated costs.
TNPA is mandated by the National Ports Act to provide, operate, and maintain lighthouses and other marine Aids to Navigation (AtoNs) to assist the navigation of vessels within commercial port limits and along the coast of South Africa.
Lighthouses, beacons, and buoys are the most common types of visual AtoNs. Virtual AtoNs are new technology that use digital signals to warn of dangers in specific locations, without the need for physical buoys or lighthouses.
The digital signals are transmitted from Automatic Identification System (AIS) stations and are received by AIS units onboard vessels. Large vessels X such as container ships and passenger ships – are required to carry AIS, but smaller vessels are not.
Therefore, visual marine AtoNs cannot be done away with.
