Spanish multinational Abengoa officially launched its third large-scale solar thermal plant on Friday, near Pofadder in the Northern Cape. It is expected to have an impact on the local community and demonstrate the viability of solar power as a sustainable source of electricity.
The parabolic thermal installation, Xina Solar One, has a total installed capacity of 100MW and follows the launch of KaXu and Khi, making it the largest such system in Africa.
“Khi, KaXu and Xina Solar One, all together, reach an installed capacity of 250MW of renewable and dispatchable energy, offset 831 000 tons of CO2 emissions every year and supply upward of 220 000 homes,” said Dominic Goncalves, vice-president of business development at Abengoa South Africa.
He said that the project delivered 1 800 jobs during the construction phase and is expected to create 80 permanent jobs during the operational phase over the next 20 years.
“Our commitment is to employ 70% South African people, although we are focusing on reaching 100%,” said Goncalves.
Electricity after sunset
Solar thermal plants such as Xina Solar One use a set of parabolic mirrors to reflect the sun’s rays to a central tower hub, which contains a salt.
Under the extreme heat, the salt melts and this is in turn used to heat water and the steam from the water is used to turn a turbine, creating electricity.
The inauguration was attended by dignitaries such as the Minister of Energy, Mr Jeff Radebe; members of the local community in Pofadder, the media; and the business fraternity.
Thanks to these projects Abengoa has helped to regenerate the economic, social, industrial and environmental fabric of this area in South Africa. During the construction phase of XiNa Solar One, job creation peaked at over 1 300 positions, to which another 80 have been added in the operation phase, the duration of which is for the next 20 years. Now that the project is operational, the plant produces clean energy to serve more than 95 000 South African households and prevents the emission of an estimated 348 000 tons of CO2 each year.
XiNa Solar One is the country’s first solar thermal plant designed to operate based on the so-called ‘energy sale windows’ that are detailed in an electricity calendar, in accordance with the agreement signed with Eskom, South Africa’s power utility and final client of the plant, to which the production at the plant is aligned. This energy sale windows corresponds to the peak hours, the periods of time with the higher consumption of electrical energy.
Unlike solar photovoltaic (PV) systems, the thermal plants, also known as concentrated solar plants (CSPs), are able to continue producing electricity even after the sun sets because the molten salt remains hot for hours.
“The efficiency of CSP plants is exceeding that of commercial PV installations. A direct comparison between those technologies is possible as both make use of the same resource, solar irradiation,” said Dr Matti Lubkoll, who teaches solar thermal energy at Stellenbosch University.
“Wind turbines tend to have a higher efficiency in terms of converting energy available in the wind into electric power,” he added.
CSP technology is still a relatively new technology in clean energy production, and the EU-inspired Desertec initiative has so far failed to get off the ground.
The project had aimed to place CSP plants in the Sahara Desert and to export electricity to Europe and create jobs in northern African countries.
IRENA’s Renewable Energy Technology: Cost Analysis Series on Concentrated Solar Power report says that, globally, renewable energy projects need to be scaled up six times to meet climate goals set out in the Paris Agreement on climate change.
The agency, however, calculates that CSP will make up just 4% of renewable electricity generation compared to 22% from PV and 36% from wind by 2050.
“As deployment of CSP technologies increased maturity follows. Increased deployment will result in component cost reduction and increased maturity in reduced cost of financing, both significantly enabling cost reduction for electricity production cost of CSP,” Lubkoll said.
A key challenge for developing CSPs is the state of the transmission network and Lubkoll highlighted the contrast of the location of projects and the availability of transmission lines.
“In South Africa the best solar resource for CSP plants (actually among the best in the world, second only to the Atacama Desert in Chile) can be found in the Northern Cape around Upington. The specific location of CSP plants in this region therefore has to consider the availability of electricity transmission infrastructure.”
By Duncan Alfreds. Source: News24
- See more info on all three solar plants here.