KaXu Solar One is South Africa’s first concentrated solar power plant using parabolic trough technology.

KaXu Solar One is South Africa’s first concentrated solar power plant using parabolic trough technology.

Abener and Teyma, two subsidiaries of Abengoa, were jointly awarded the engineering, procurement and construction (EPC) contract for the KaXu Solar One concentrated solar power project.

Rioglass manufactured the mirrors and Schott is the supplier of HCEs for the parabolic troughs used in the project. Siemens supplies the steam turbine for the solar thermal power plant. Mott MacDonald conducted the feasibility study for the project.

KaXu Solar One is a 100MW concentrated solar power (CSP) plant being constructed on a 1,100ha site near Pofadder in the Northern Cape Province of South Africa. It will be the first CSP plant in South Africa to use parabolic trough technology. The solar power project, scheduled for commissioning in 2015, will supply clean energy to approximately 90,000 African homes while offsetting 315,000t of CO2 emissions per year.

The KaXu Solar One project is jointly owned by Abengoa Solar (51%), state-owned Industrial Development Corporation (IDC, 29%), and a community trust owned by the Broad-Based Black Economic Empowerment (BBBEE, 20%).

KaXu Solar One is one of the 28 renewable energy projects announced by the South African Department of Energy (DoE) in 2011. South Africa has set a goal to achieve up to 17,800MW of renewable energy by 2030 in an effort to reduce its dependence on oil and natural gas resources.

Ground breaking for the KaXu Solar One project was held in November 2012. The project is expected to create about 1,500 jobs during the construction phase and 65 permanent jobs during operation.

The KaXu Solar One facility will encompass a 310ha solar field installed with 1,200 parabolic trough solar collector assemblies (SCA) supplied by Abengoa Solar and assembled in 300 loops, with each SCA comprised of ten modules.

The pivoting concave mirrors of the parabolic troughs focus sun light on to 4m long evacuated type receiver pipes or heat collection elements (HCE) running along the centre of each trough. The absorbed heat, in turn, heats up the oil flowing through the pipes. The heat transferred through the fluid is used to create steam to drive a 100MW turbine for power generation.

The solar thermal power plant, expected to operate for 30 years, will use the dry cooling method and provide three hours of thermal storage capacity using a two-tank indirect molten salt based thermal energy storage system. The stored thermal energy can be used to generate electricity for five hours after the sunset.

The power generated from the KaXu Solar One plant, which is estimated at 330,000MWh per year, will be sold to the South African electricity utility Eskom under a long-term power purchase agreement.

A 132kV overhead transmission line will be built to connect the KaXu Solar One facility to the Eskom Network through Eskom’s Paulputs Transmission Substation in Northern Cape, which is located 5km away from the plant site.

The International Finance Corporation, a member of the World Bank Group, is providing direct financing of R1.25bn ($143m) for two CSP projects in South Africa including KaXu Solar One and the 50MW Khi Solar One project, which is also being developed by Abengoa. The IFC has also arranged $264m of parallel loans for the construction of these two projects.

The lenders co-ordinated by IFC for the KaXu Solar One project include Clean Technology Fund (CTF), Development Bank of Southern Africa (DBSA), FirstRand Bank, IDC, and Nedbank.