Bookport concentrated solar power (CSP) plant in South Africa, built by Sener, Acciona and TSK, has set a new African record for the continuous, round-the-clock supply of electricity. Within the first month of commercial operation, the newly-inaugurated 50 MW Bokpoort CSP plant, produced electricity for a continuous period of 161 hours, equivalent to almost six days of continuous, full-load electricity – an African record.
CSP technology is considered an intermittent source of power which supplies electricity during daylight hours, when demand is highest. Nevertheless, Bokpoort’s design enables it to continue supplying electricity long after the sun has set thanks to a molten salt energy storage facility that can accumulate 9.3 hours of electricity production, the highest power storage facility on the African continent.
Round the clock electricity supply from a solar power plant is a significant milestone for South Africa and for the renewable industry as a whole, as it allows CSP technology to approximate the continuous power supply of conventional technologies such as hydroelectric, thermal or gas-fired power plants.
In South Africa the country’s daily evening peak demand is from 5 pm to 9 pm and the newly introduced CSP Peak tariff means that developers are encouraged to have thermal storage capacity.
Bokpoort CSP has shown that due to the good design of the plant and the solar radiation available at the site, its 9.3 hours of thermal storage can easily be extended to allow round-the-clock continuous operations.
Nandu Bhula, CEO of Bokpoort CSP plant, declared: “Globally the biggest challenge of CSP has been its ability to produce energy consistently long after sunset. The performance of this plant is a clear indication that CSP technology can be used as a base-load capacity option in the same way as conventional power plants.”