In the Robben Island Microgrid, there are three key power production aspects. The first of these is a solar farm, consisting of 1960 mono-crystalline modules that produces 666.4 kW of power.

The second is a battery bank, consisting of 2420 lithium-ion battery cells, ready to store 837 kWh worth of electricity and supply 500 kV worth of peak power.

The third aspect is the diesel generators, which supply power to the island when the solar farm is not producing energy (for example at night), and the battery bank is depleted.

Combined, these three power production elements, coupled with a set of smart controllers, supply Robben Island power – all of the time.

The microgrid control system is based on a distributed intelligence approach which ensures that the grid behaves smartly for seamless power production. The only centralised component in the system is a data-collection system, similar to a small SCADA (Supervisory Control and Data Acquisition), which allows for set points to be altered and measured values to be recorded.

The Robben Island Microgrid is a great case study to explore the true value of solar PV and battery combinations, because it is already independent of the central grid. During its first two months of operation, the island produced 187 000 kWh clean electricity through solar power, resulting in 53 685 litres of diesel being saved, an equivalent of 495 tons CO2 emissions.