Bokpoort CSP

Bokpoort CSP is a concentrated solar power (CSP) thermal energy power plant, located near Groblershoop in the Northern Cape province of South Africa. The project was procured pursuant to the Renewable Energy Independent Power Producer Procurement Programme (REIPPPP) initiated by the South African Department of Energy. The Bokpoort Plant has a thermal molten salt storage capacity of 1‚300 MWht equivalent to around 9.3 hours full load generation. The plant synchronised for the first time on the South African Grid in November 2015, after a construction period of 29 months.

On 23 September 2013 the groundbreaking ceremony for the commencement of construction at the Bokpoort Concentrated Solar Power plant was held in the presence of ACWA Power Chairman Mohammad Abunayyan, Mayor Paul Vries and other dignitaries in Groblershoop, South Africa. Power developer ACWA Power Solafrica’s Bokpoort concentrated solar power (CSP) plant reached full operation capacity, ahead of schedule, in December 2015. On 16 March 2016 Trade Ministers from South Africa and Saudi Arabia jointly inaugurated the Bokpoort Concentrated Solar Power (CSP) Project, marking the official launch of the R 5 billion ($339.93 million) project. The South African solar power plant has set a new African record (25 March 2016) for the continuous, round the clock supply of renewable electricity for 161 hours. On 29 April 2021 Revego Africa Energy Limited announced a 12 percent stake in the plant, for R 204 million ($14.8 million). Revego is buying the stake from Métier, a South Africa private equity firm, who manages the Lereko Metier Sustainable Capital fund.

Bokpoort CSP has a gross capacity of 55 megawatts (MW) and 50 MW net. The solar field covers an area of less than 300 hectares (741 acres). With its 8600 solar collector elements (SCE) the solar field captures the solar energy. Through the heat-transfer fluid (HTF) circulating through large steam generators, the energy is transformed into steam at 103.6 bar and 380 °C. The 50MWe conventional steam turbine will then use the steam flow to generate electricity and two molten salt tanks will store excess heat energy for conversion into electric energy after sunshine hours.

One remarkable feature of the plant is the large energy storage capability. It is the world’s first commercial utility-scale CSP plant to have more than nine hours of storage, which provide the ability to deliver power well after sunset or when power demand is highest, effectively making it a peaking power plant. Bokpoort CSP Owners led by ACWA Power International (Saudi Arabia) describes this system as the largest thermal storage system ever built for a CSP plant of its size and capacity. The Bokpoort thermal energy storage consists out of one hot and one cold storage tank (each 40 m diameter and 14 m height) filled with 39,100 tons of environmental friendly molten salt (potassium and sodium nitrate).

The solar field consists out of 180 loops grouped into 8 sub-fields with a total of 8600 SCEs using SENER Trough Technology with Flabeg Glass Mirrors. There are in total 241,920 mirrors installed which have a total of 658,000 m2 of reflective surface.

The plant was built, starting in September 2013, by the EPC consortium of Spanish companies Acciona, SENER and TSK and South Africa’s Crowie. During peak construction period the project employed more than 1300 persons on site.

Power station data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).