Inaugural Lecture: Professor Craig McGregor

Join us for Prof Craig McGregor's professorial inaugural lecture – Sun, steel and storage: solar thermal in South Africa’s energy future, hosted by the Faculty of Engineering.
 

Professor Craig McGregor
Acwa Chair in Concentrating Solar Power
Mechanical and Mechatronic Engineering
Faculty of Engineering
Title: Sun, steel and storage: solar thermal in South Africa’s energy future

Event details
Date: Tuesday 19 May 2026
Time: 17:30 SAST
Venue: Room A5056, Main/General Engineering Building, Faculty of Engineering, 156 Banghoek Road, Stellenbosch
Format: Hybrid event

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Sun, steel and storage: solar thermal in South Africa’s energy future

South Africa’s ageing coal fleet provides most of the country’s electricity, but these power plants are reaching the end of their lives. South Africans have already experienced what happens when they fail: years of loadshedding that disrupted households, businesses and the economy. Within two decades, the country must find new sources for the bulk of its power. In his inaugural lecture, Prof Craig McGregor argues that one proven technology has been overlooked in this transition, namely concentrating solar power (CSP), which uses mirrors to focus sunlight, generate heat, and store that heat in tanks of molten salt for use after dark.

South Africa is one of the best places on earth to build CSP plants. The Northern Cape receives more direct sunlight than Spain or China, the world’s two leading CSP markets. Seven CSP plants already operate in the Northern Cape, representing over R85 billion in private investment. Two of these, Bokpoort and Redstone, provide operational data to Stellenbosch University’s Solar Thermal Energy Research Group (STERG) through the ACWA Power Chair in Concentrating Solar Power.

Unlike conventional solar panels, which rely on imported silicon cells from China, CSP plants are built from steel, concrete and glass, all of which South Africa manufactures domestically. The lecture presents evidence that more than 40% of current CSP project value has been sourced locally through genuine heavy manufacturing: steel fabrication, heat exchangers, storage tanks and civil construction. The Stellio heliostat, a mirror system conceived in South Africa and designed from the outset for local production, is now deployed commercially across four plants in China. It was designed for South Africa; China said yes instead.

Storing energy as heat in molten salt costs roughly a tenth of storing it in batteries, and CSP plants can dispatch electricity for 12 to 16 hours after sunset, which is far beyond the economic limit of battery systems. When the technologies are compared on the basis of power available on demand, CSP with storage costs over 40% less than solar panels paired with batteries.

Yet South Africa stopped purchasing CSP after only four procurement rounds, just as prices were falling steeply. Solar panels and wind continued to be purchased, continued to get cheaper, and now appear more competitive, simply because they were given the opportunity that CSP was denied.

Prof McGregor concludes that South Africa has the solar resource, the industrial capability and the proven technology to build CSP at scale. What remains is the decision to invest again. STERG’s research programme, supported by the ACWA Power Chair, is working to close the remaining gaps.

Biography

Prof Craig McGregor is a professor in Mechanical and Mechatronic Engineering at Stellenbosch University (SU), where he holds the ACWA Power Chair in Concentrating Solar Power and leads the Solar Thermal Energy Research Group (STERG). His research spans concentrating solar thermal systems, thermal energy storage, green hydrogen, and energy systems engineering, with a focus on the role of solar thermal technology in South Africa’s energy transition.

Before joining SU in 2019, Prof McGregor spent over 20 years at Sasol, where he led the South African development of the Stellio heliostat in collaboration with German engineering firm SBP Sonne. Stellio won the SolarPACES innovation award in 2015 and has since been deployed commercially in China. At Sasol, he also led two chemical technologies from development through to commercial operation.

Prof McGregor’s current work at STERG draws on operational performance data from the Bokpoort and Redstone CSP plants, provided through the ACWA Power Chair partnership. His group’s research addresses CSP cost reduction, grid integration modelling, and the economics of long-duration thermal energy storage in the South African context. Since joining SU, he has supervised over 40 postgraduate students and postdoctoral researchers.

He has a particular interest in how engineers learn to work effectively with artificial intelligence (AI) tools, and has developed training frameworks for both students and academic staff in the use of generative AI in engineering education.

Prof McGregor holds the Bill Neale-May gold medal from the South African Institution of Chemical Engineers, awarded for contributions to process technology. His work has been published in Solar Energy, Journal of Energy Storage and Energies, among others.