John Cockerill to Supply Thermal Receivers to Redstone CSP Plant in SA

John Cockerill, a Belgium-based engineering company, has revealed that it will supply molten salt solar thermal receivers to Redstone’s 100 MW Concentrated Solar Power Plant (CSP) in the Northern Cape Province of South Africa.

Developed by Saudi Arabia-based ACWA Power and constructed by EPC SepcoIII, the Redstone CSP plant is expected to supply 2,00,000 households with clean power and save nearly 440,000 tons of CO2 emissions per year upon completion.

The receivers will be placed on top of Redstone’s solar tower, allowing the project to efficiently store energy and produce power round the clock.

With a total investment of around $162 million, the project has secured financing from leading international and South African financial institutions including African Development Bank (AfDB), ABSA Bank, Development Bank of Southern Africa (DBSA), CDC Group, Nedbank Limited, etc.

The Redstone CSP plant, which forms part of the South African Renewable Energy Independent Power Producer (REIPP) Procurement Program, is the first project financed CSP with molten salt central receiver project in the world and one of the largest investments in South Africa under the REIPP.

John Cockerill says that the state-of-the-art technologies utilized in the project will produce electricity through the day due to the use of molten salts as heat-transfer fluid. These salts will feed the receiver at the top of the tower and will be heated to 565°C. Once brought back down, they will conserve heat for up to 12 hours, enabling electricity to be produced night and day.

Energy storage is a particular challenge when storage needs last for more than a few hours; however, with the use of molten salt solar thermal receivers, power will be available twenty-four hours a day, said the company.

CSP refers to a type of solar technology that uses giant mirrors to direct sunlight on to a receiver, which converts it into heat. There are several types of such mirrors, they can parabolic troughs or rounded dishes, or power towers.

Concentrated solar power can be a lot more effective than solar photovoltaic technology. This is because PV uses solar panels that can only work when there is sunlight, meaning electricity can only be generated as long as sunlight falls on the panels.

CSP on the other hand, stores the sunlight as heat, which can be used at a later time, and even when there is no sunlight. In effect, CSP works like any other thermal power plant.

Rajit Nanda, ACWA Power’s Director of Portfolio Management and Acting Chief Investment Officer, said, “ACWA Power is proud to lead the development of the largest renewable energy investment in South Africa to date, the Redstone CSP project, and by while playing a leading role in supporting South Africa’s decarbonization efforts.”

Beyond solar energy, the John Cockerill Group is working on several projects that combine renewable solutions, in particular, green hydrogen.

The Redstone solar power plant equipped with a John Cockerill solar receiver will be the fifth John Cockerill solar tower in the world and the second project to be undertaken by the company in South Africa.

The company’s solar power plants currently in service include the 50 MW Khi Solar One plant in South Africa and the 50 MW Haixi plant in China, which recently achieved a production record.

In Chile, a third solar tower is in operation, the Cerro Dominador power plant (110 MW), which was connected to the grid recently. A fourth power plant, which is also being developed by ACWA Power, is currently under construction in Dubai and is expected to be connected to the electricity grid by the end of the year.

CSP technology is increasingly gaining popularity in the Middle East and North Africa (MENA), where it is of interest for its local content potential and because, unlike PV, it can easily store thermal energy, within massive tanks of molten salt, for use after sundown.

MENA is where most recent cost reductions have come from. In July 2017, for example, a Dubai Electricity and Water Authority tender attracted a record-low CSP bid of $94.50 per megawatt-hour. In 2019, ACWA Power was reported to be targeting a cost of close to $50 per megawatt-hour at another Dubai project, the 950-megawatt Noor Energy 1 hybrid CSP and PV plant.