Stellenbosch University researchers believe concentrating solar power (CSP) has an extremely bright future in South Africa and could signal a tremendous economic opportunity for the country.
In terms of renewable-energy alternatives, they believe CSP is one of the most important electricity generation technologies for South Africa in the twenty-first century.
CSP supplies electricity to demand, as long as it is scaled appropriately. Its advantage is its very efficient thermal storage and hybridisation. Concentration of solar radiation is used to achieve higher operating temperatures. This is done with reflectors, typically mirrors.
Stellenbosch University Centre for Renewable & Sustainable Energy Studies director Professor Wikus van Niekerk told a packed gathering of the South African National Energy Association (Sanea), in Cape Town, that South Africa’s abundant sunshine made it an extremely viable technology.
“South Africa has 50% more solar irradiance than Spain and 20% more than North America,” he said.
Storage is a concern for solar electricity generation, especially bearing in mind South Africa’s electricity demand peak from 18:00 to 21:00 on weekdays, on the fringe of sunlight hours.
Van Niekerk explained that, fortunately, heat could be efficiently stored within CSP plants and dispatched when needed.
There are around 34 CSP plants in the world, including a handful of projects in South Africa, such as the 100 MWe CSP plant to be built north-west of Upington.
“After the sun has gone down, it can still generate electricity for 9 to 12 hours. The plant also aims to offset around 450 000 t/y of carbon dioxide,” said Van Niekerk.
He said countries like South Africa, Namibia, Botswana, Australia, Spain and Chile were suited to this kind of technology, particularly in areas where there are few clouds.
CSP technology forms only a sliver of the renewable-energy projects under the government’s Renewable Energy Independent Power Producer Procurement Programme.
Stellenbosch University Solar Thermal Energy Research Group director Paul Gauché also believes there is huge potential in CSP technology, particularly as it is competitive in terms of price.
“We see CSP as a potential ‘next big thing’ for South Africa. We have much more sun than we’ll ever need and now have immediate opportunities to leapfrog South Africa. We could be a world leader in this…not at the moment, but we have the potential,” he said.
Gauché is coordinating a university-developed CSP technology that could be piloted from 2014. His own research looks at systems analysis of CSP as part of South Africa’s future energy generation mix.
He said CSP could provide the country with a certain amount of energy security and was a big advantage, as it was not dependent on fuel prices.
“We could be vulnerable to fuel prices in the future and that means the entire electricity network becomes vulnerable. We need something to bail us out – and that’s CSP,” Gauché told the Sanea gathering.
The researchers would like to see added CSP capacity down the line from the Northern Cape to Cape Town.