Reported from CSPPLAZA:Abengoa announced on March 31, 2017 that it had achieved the completion of the financial restructuring.
Dr. Michael Geyer, Vice-President for Concessions and Business Development E&A of Abengoa Energia recently reported to the CSPPLAZA correspondent, that “during the restructuring process the construction of the 100 MW CSP plant Xina in South Africa and the Waad Al Shamal hybrid plant with 1390 MW Combined Cycle with 50 MW parabolic trough field in Saudi Arabia had progressed as scheduled. Therefore, Xina will reach scheduled commercial operation by August this year, as scheduled”.
Dr. Geyer also reported that “the Atacama-1 project in Chile, Abengoa is currently completing construction of the 100 MW PV part and expects to resume construction of the 110 MW CSP part later this year. Atacama -1 is located in the Atacama Desert, which has the highest solar radiation in the world. The CSP part of the Atacama-1 project is a 110 MW molten salt storage (TES) tower designed with 17.5 hours of molten salt storage, thereby guaranteeing 24 hours of production, 365 days a year for the mining industry. This project was the winner of an international competition organized by the Ministry of Energy of Chile and CORFO to support the construction of the first CSP plant in South America. It became the first CSP project to successfully compete with all other conventional and renewable technologies for a baseload electricity power purchase agreement”.
Figure: Abengoa solar company vice president Michael Geyer
Inflexion point: Molten Salt Storage for 24/7 Solar Power Generation
At its 280 MW Solana plant in Arizona, Abengoa has built world’s largest molten salt storage system in parabolic trough plants. In the Atacama-1 project, Abengoa will use molten salt both as a heat transfer fluid as well as a thermal energy storage medium for continuous 24/7 operation. The molten salt concentrating tower technology raises the operating temperature from the app. 400ºC achieved in parabolic troughs up to 560ºC in the tower receiver in order to increase turbine cycle efficiency and almost doubling the thermal capacity of the storage tanks. While up to a maximum temperature of 400ºC parabolic trough plants could use carbon steel for both the cold and hot tanks, for the over 500ºC in the hot tanks of molten salt towers high alloy stainless steel is required.
The developers of the first commercial molten salt tower plants – Gemasolar in Spain and Crescent Dunes in the US report – both had recently reported that were facing some initial challenges with their molten salt hot tanks.
Dr. Geyer told CSPPLAZA correspondent that, “the daily charging and discharging cycles of the solar tower’s hot tanks with molten salt over 500ºC additionally imposes upon the hydraulic stress cycle a very high thermomechanical stress cycle. Very strict requirements in design, material choice, welding and quality control need therefore to applied to avoid the risk of faults and leaks. Having learnt from experience at our R&D test site in Spain, Abengoa has developed its own technology to avoid such issues”.
China’s Market and International Cooperation
With over 2,000MW total capacity of installed CSP plants, Abengoa is a world leader in the engineering, procurement, construction and operation of CSP plants worldwide.
Michael Geyer commented that, “Chinese CSP market is promising and therefore attracts leading international CSP firms. Chinese developers naturally intend to maximize the local content of their CSP plants starting from the first plant in order to minimize cost and to build up a human and industrial knowledge base for the sustainable implementation of China’s future CSP plants. However, it has taken since the beginnings 1997 almost 20 years for Abengoa to achieve the technology upscale and bankable maturity of today’s advanced parabolic trough and solar tower CSP plants. Only some 20 months are left for the currently scheduled commissioning date of China’s first CSP round of demonstration program. To make the ambitious CSP projects of China’s first round a full success, it should be made use as much as possible of the world wide CSP knowhow and experience. We are offering our full engineering, procurement, construction and operation experience to Chinese developers and EPC partners. We have cooperated with international partners worldwide in over 20 CSP projects and have together made them a great success. We put our full faith on this kind of cooperation and are looking forward to cooperating with Chinese companies in domestic and international projects.”
Michael Geyer implied that，“ the 20 months period left for the first round of China’s CSP demonstration projects is considered extremely tight, according to Abengoa experience. In Spain, construction of the first 50 MW CSP plants took around 36 months that Abengoa could reduce later to 17 months construction time when replicating a 50 MW parabolic trough. This was possible, since Spanish climate allowed to work on the site without interruption along all the year day and night. First 100 MW CSP plants in new markets like South Africa required some 27-36 months of construction time also in a climate without prolonged winter frosts. We therefore have our fullest respect for our Chinese constructor colleagues that intend to construct the first 50-100 MW CSP plants in Chinese regions with long periods of deep frosts in very remote areas”.
Finally, it is to note that Abengoa also has the EPC experience in China, as had successfully designed, constructed and brought into operation a desalination plant in seaside Qindao city.