The “tremendous” success of the Robben Island solar photovoltaic (PV) microgrid project lends itself to “fantastic” replication potential, as it serves as a model example for retrofitting existing energy systems with solar and batteries to significantly reduce fossil fuel consumption and stabilise energy supply, proclaims solar energy company SOLA Future Energy CEO Dominic Wills.
“The microgrid has been running in auto mode for a few months, with negligible issues, and it has produced 187 000 kWh of clean electricity through solar power during its first two months of operation.”
During its first two months of operation, the island saved 53 685 ℓ of diesel, Wills says, with significant cost savings for the Robben Island Museum, which manages the island.
“In a country marred by government controversy and looming nuclear deals, it is incredibly inspiring to see an innovative renewables project implemented on one of South Africa’s trademark tourist destinations through cooperation from several government departments.”
Wills posits that the microgrid contains immense potential for replication in South Africa and Africa, considering that much of the continent remains off grid, or grid- connected but plagued by expensive tariffs and unreliable power supply.
This is being facilitated by SOLA Future Energy, as the company believes that Africa’s future depends on affordable, clean and accessible energy. It is pursuing this objective by actively harnessing, storing and distributing low-cost solar energy, thereby enabling African business and industry to thrive.
The company has, to date, designed and constructed more than 18 MW of solar projects across South Africa, including ground-mounted, rooftop and parking solutions. It is also working on a microgrid project on the West Coast, in the Western Cape, which Wills indicates will launch in the first quarter of 2018.
Several megawatt solar projects are also in the pipeline, with Wills highlighting 5 MW of projects across financial services provider Old Mutual’s portfolio, which includes Gateway Shopping Centre, in Durban; Cavendish Square Shopping Centre, in Cape Town; and Riverside Mall, in Nelspruit.
The company also opened a Johannesburg office in June this year to satisfy demand from the African market.
The Western Cape Department of Tourism awarded the Robben Island project in April 2016, and it was commissioned in July and officially launched in October. The project is being operated by SOLA Future Energy.
The microgrid consists of three power production elements. The solar PV farm consists of 1960 mono-crystalline modules with a power supply of 666.4 kW. The battery bank, consisting of 2 420 lithium-ion battery cells, can store 837 kWh, with a maximum output of 500 kVA. The diesel generators are used when no solar or battery storage is available.
The solar PV field produces excess power during the day, compared to the load. The excess energy is stored in the battery bank during daylight. After the sun sets, the batteries continue to power the island’s evening load, with diesel as a backup in case the batteries become depleted.
Multiple controllers between the power production elements balance the power supply and create a smart microgrid, ensuring a seamless supply of power. This is notable, as thousands of tourists visit Robben Island, 100 staff members live there permanently and it contains a lighthouse and a desalination plant. Therefore, the island’s energy requirements are quite high, at just under two-million kilowatt-hours a year.
The microgrid will save Robben Island about one-million kilowatt-hours a year of electricity, meaning that at least half of the island’s electricity needs are met by the solar and battery component. This means that an estimated 235 000 ℓ of diesel will be saved by the island yearly, which will also decrease costs associated with transporting this to the island.
The microgrid will meet the energy needs of the island, with no external supplementation, as the island is not connected to South Africa’s main energy grid. Robben Island is also embarking on its own energy-saving initiatives, such as retrofitting, which will further reduce its energy consumption, notes Wills.
Robben Island is ideally suited to this solution, as it boasts a good solar resource, and its close proximity to the sea keeps the panels relatively cool, thereby enhancing their performance.
“SOLA was delighted to have been selected to undertake this project. It was particularly inspiring to work with the Department of Tourism on such a forward-thinking project – although the uptake of solar PV is soaring, the battery-storage market is new. We are privileged to be associated with such an innovative project – the first of its kind in South Africa,” concludes Wills.