A new solar plant that can supply electricity even when the sun sets has been launched in the Northern Cape.
The 100MW Karoshoek Solar One project has gone live 30km east of Upington as part of the government's Renewable Energy Independent Power Producer Procurement Programme.
"The plant will provide power to approximately 100 000 households," Karoshoek Solar One CEO Niroshma Chetty told News24.
She added that, during construction, 1 500 jobs - of which 1 300 were local - had been created and that 62 people would be directly employed during the operational phase.
"Not many projects have been completed on time and within budget, as we have done today. It has been a massive effort, involving many teams of people," said Chetty.
Unlike a traditional solar photovoltaic (PV) system, the Karoshoek facility is based on concentrated solar plant (CSP) technology.
The installation will plug into the national grid at a time when Eskom is once again engaging in load shedding as a result of a lack of sufficient coal at traditional power stations.
CSPs do not require coal to produce electricity and do not produce any of the waste associated with either coal or nuclear power plants.
"We have shown once again that solar energy has a huge role to play in South Africa. With renewable energy we can combine the provision of power with positive social and environmental outcomes. Solar technology allows us to produce energy without releasing carbon or other harmful emissions. It is a crucial part of our energy mix," said Chetty.
Several parabolic mirrors focus the sun's rays onto a collector which holds a fluid. This fluid, which often consists of salt among other materials, will use the heat to turn a turbine, much like in a coal-powered plant.
The thermal fluid retains heat for several hours, enabling the turbine to generate electricity during the day and at night.
A solar PV system needs additional battery storage to deliver power after the sun sets.
"CSP compliments other renewables - such as wind and PV - because of its ability to store energy, making it a dispatchable power plant that can be operated as a peaking power plant or baseload power plant," Chetty explained.
"CSP is different from PV, as the power generated by a CSP plant can be stored and supplied after dark. This plant can store energy for five hours. This enables the plant to continue to supply electricity to the grid after sunset."
According to the International Renewable Energy Agency (Irena), the levelised cost of electricity from CSPs is higher than PV or wind systems, though the agency was careful to point out that in high sunlight areas, the costs could be significantly less.
Data from Stellenbosch University's Centre for Renewable and Sustainable Energy Studies shows that the Northern Cape province is ideal for solar power installations.
Northern Cape ideal
The province has Direct Normal Solar Irradiation of between 3 000kWh/m 2 and 3 200kWh/m 2 , the highest in the country.
According to Irena data, SA has seen significant installation of solar power since 2013. There has been a net addition of 2 173MW of solar PV and, since 2014, a net addition of about 300MW in CSP.
Chetty said that the Karoshoek Solar One project was the fifth CSP in the province, proving how ideal it was for the conditions.
SA has a cumulative total of 2 486MW of solar power generation, of which 300MW is CSP.
Commercial funding for the Karoshoek Solar One project came from ABSA, DBSA, IDC, Investec, Nedbank, Standard Bank, PIC and Vantage Capital.