Utility Scale: 10 Biggest Solar Projects In South Africa

South Africa's energy mix is diversifying, with renewables now making up 25% of the country's total installed generation capacity. The north-western region of the country is endowed with vast tracks of land where sunshine is abundant and intense, particularly in the Northern Cape. This has attracted several independent power producers (IPPs) into the region.

In contrast, concentrated solar power (CSP) farms use mirrors to focus sunlight onto a single point and can store the energy they produce in thermal systems for use at a later stage. CSP farms are only viable in areas with high direct normal irradiation - a measure of the intensity of sunlight - such as the arid regions of the Northern Cape. CSP solar farms that use thermal energy storage systems are also referred to as thermo-solar power plants.

TechCentral conducted desktop research into the largest, utility-scale solar power projects that feed energy into South Africa's grid as part of government's renewable IPP programme. These are the 10 largest solar farms, based on installed capacity, in South Africa

Spread over 850 000sq m near Pofadder in the Northern Cape, this 100MW thermos-solar power plant is the biggest solar power complex in Africa when combined with the adjacent Kaxu Solar One solar power plant mentioned further down the list.

The Xina Solar One plant makes use of cylindrical-parabolic collectors and a thermal storage system to generate electricity. The parabolic concentrators are made of curved mirrors that track the sun and concentrate solar energy onto synthetic oil-filled absorber pipes.

The oil in the pipes is heated to 395°C and transferred to a heat exchanger. The exchanger then heats water to generate steam, which turns the turbine and generates electricity.

The heat from the oil is also used to heat 47 000 t of molten salt stored in thermal energy storage tanks. This system can generate electricity for up to five hours after sunset.

Karoshoek Solar One , also referred to as the "Ilanga" project, is a 100MW CSP plant 30km east of Upington in the Northern Cape. Karashoek also makes use of arrays of curved cylindrical panels, known as parabolic troughs, to concentrate sunlight into a receiver tube that is filled with a heat transfer fluid. The heat transfer fluid heats water into steam, which turns a turbine and generates electricity.

Karoshoek went live in November 2018 and is expected to feed the national grid for the next 20 years or more.

Kathu Solar Park is named after the Khatu region of the Northern Cape in which the 100MW CSP plant is situated. Operations on this site commenced in January 2019 using parabolic trough technology and a molten storage system that can produce electricity for 4.5 hours after the sun has set.

According to the project website, Khatu will displace six million tons of carbon dioxide over its initial 20-year lifespan.

Kaxu Solar One is a 100MW thermos solar plant located in the same complex as the Xina Solar One plant in Pofadder. When combined, the two plants make up the largest solar power complex in Africa. Kaxu's molten salt storage system has the capacity to generate electricity for 2.5 hours without sunshine. The parabolic trough collectors used at Kaxu are 7.5m wide, 150m long and 3m high.

The Adams Solar PV2 solar park is a 75MW plant located in Hotazel in the Northern Cape. According to its owner Enel Green Energy, the plant produces 167GWh of energy per year and assists in displacing 171 700 metric tons of carbon dioxide while meeting the energy needs of 100 000 households annually. Construction on the site began in 2017 and the plant became operational that same year.

Dyason's Klip is situated in Upington and majority-owned by Norwegian power producer Scatec Solar. The project is the first phase of three 86MW PV farms that will have the combined generation capacity of 258MW.

According to the project's website, the first phase of Dayson's Klip produces 217GWh of electricity per year.

Once completed, the 258MW Dyason's Klip solar power complex is expected to provide energy to around 120 000 households and lead to the displacement of more than 600 000 t of carbon emissions annually. The last of the three solar plants under construction is expected to reach commercial operation within the next few months.

The Jasper Power Plant was jointly developed by SolarReserve, a US developer of utility-scale solar power projects, Kensani Capital Invest