The clean energy unit of JSE-listed Sasol, which is best known for the conversion of coal and gas into fuels and chemicals, is moving ahead with a front-end engineering and design (FEED) study for a utility-scale solar power plant in South Africa using a solution provided by BrightSource Energy, of the US.
Sasol confirmed on Thursday that it had selected the Californian group’s ‘power tower’ solar thermal technology for a possible concentrated solar power (CSP) project in South Africa, following a worldwide review of available technologies.
BrightSource and French energy equipment vendor Alstom would conduct a comprehensive FEED study for the domestic market and Sasol would use the information to determine whether or not to deploy the solution.
Sasol New Energy MD Henri Loubser told Engineering News Online the study should be completed by the third quarter of the 2012 calendar year. Thereafter, the group would make a decision on whether it planned to pursue a development that could involve an investment of “billions of rands”.
The location of the project had not been decided and would be informed by South Africa’s solar resource map.
The study would also determine the scale of any possible development – BrightSource Energy was currently building the 370 MW Ivanpah project in California’s Mojave Desert, which is scheduled to start production in 2013.
Loubser said the CSP project had the potential to expand Sasol’s new energy portfolio that was focused on the development of clean-coal solutions, such as underground coal gasification and carbon capture and storage, as well as low-carbon electricity solutions, including CSP.
The FEED study would not be completed in time for Sasol to submit a project proposal for the Department of Energy’s (DoE’s) second bid window under the Renewable Energy Independent Producer Procurement Programme, which would close in March. However, it could participate in subsequent rounds.
Government aimed to procure and initial 3 725 MW of renewables capacity by 2016, including capacity arising from CSP developments.
In December, the DoE named the first 28 preferred bidders under the programme – including two CSP projects, 18 solar photovoltaic (PV) projects and eight onshore wind projects – representing a combined potential capacity of 1 415.52 MW. The two solar CSP projects were identified as Khi Solar One (50 MW) and KaXu Solar One (100 MW).
Bidders had until June to advance their projects to financial closure, with a price cap of 285c/kWh having been set for the CSP developments.
Under South Africa’s current Integrated Resource Plan for electricity, the country is expected to double its generation capacity to more than 80 000 MW by 2030 and integrate nearly 18 000 MW of renewables capacity over the same time horizon.
Loubser said the Sasol had decided to focus on the power tower CSP solution as it was a less mature technology than solar trough CSP and there was, thus, probably greater potential to participate in the reduction of the levelised cost of production. Competition in the area of solar PV was also so robust that Sasol did not feel it could add much value.
BrightSource Energy president and CEO John Woolard described Sasol’s selection of its technology as a significant milestone in the company’s ambition to expand its solar thermal power systems globally.
The technology employs software-controlled mirrors, called heliostats, to reflect the sun’s energy to a boiler atop a tower to produce high temperature and high-pressure steam. The steam is then integrated with conventional power plant components to turn a turbine and produce power.
The technology employs an air-cooling system to convert the steam back into water in a closed-loop cycle, which reportedly uses 90% less water than wet-cooling parabolic trough plants.
Senior VP of communications and government affairs Joe Desmond told Engineering News Online that BrightSource had made significant advances in recent years in heliostat design, operation and control, as well as in matching steam, temperature and pressure to achieve high levels of operating efficiency.
But he also stressed that facilities lend themselves to localisation opportunities, as they were steel, concrete and glass intensive. He noted that Spain had raised the local content of their systems from 50% to 80% over the past decade, while localisation levels in the US had breached the 65% level.
In South Africa, the company was working with Alstom to identify and develop CSP prospects, but Desmond said the relationship with Sasol emerged following the South African company’s review of the CSP technology offerings available globally.
Desmond described South Africa as an ideal location for CSP projects, owing to its favourable direct normal irradiance, which was among the best globally, the country’s growing demand for power and the fact that there was access to transmission networks.
“South Africa is an ideal location for CSP and the opportunities are also spread across several locations in the country,” he enthused.