European project RAISELIFE to enhance the lifetime of materials for Concentrated Solar Power
In Concentrated Solar Power (CSP) plants, the quality and durability of the employed functional materials have a high impact on the cost of the produced solar heat or electricity. Eleven European partners from the R&D sector, universities and industry affiliated together with the Moroccan Research Institute of MASCIR and the Israeli company of BrightSource to work during the next 4 years on improving the lifetime of key materials used in CSP.
RAISELIFE (Raising the Lifetime of Functional Materials for Concentrated Solar Power Technology) focuses on extending the in-service lifetime of the following five key materials:
1) Protective and anti-soiling coatings of primary silvered-glass reflectors,
2) High-reflective surfaces for heliostats consisting of silvered ultra-thin glass reflectors,
3) High-temperature secondary reflectors,
4) Receiver coatings for solar towers and line-focus collectors,
5) Corrosion resistant high-temperature metals and coatings for steam and molten salt application.
The project is funded by the European Commission with a total budget of EUR 10,509,246.50 (EU contribution of EUR 9,291,722.75). It is coordinated by Dr. Florian Sutter from the German Aerospace Center, DLR, and will be carried out by a consortium of several organizations (industrial partners, SMEs, universities and research organizations) from both the concentrating solar thermal and the materials science areas, offering a broad set of interdisciplinary expertise. Besides European partners from Germany (DLR, Fraunhofer, DECHEMA and Flabeg), Spain (CIEMAT, Universidad Complutense de Madrid and INTA), France (PROMES, Corning and Vallourec) and Italy (Soltigua), the consortium includes two parties from the associated countries of Israel (BrightSource Industries) and Morocco (MASCIR), giving access to in-service testing in CSP relevant environments and commercial installations. The scope of the project has been significantly shaped by the leading EPC (engineering, procurement, construction) of solar tower technology, BrightSource, who constructed Ivanpah, the world’s largest solar tower plant. This unique constellation allows a direct transfer of the project results into new commercial central tower plants in less than 5 years and will contribute to solve the most urgent challenges of the existing commercial plants, such as high temperature oxidation of the absorber coatings of metallic receivers or reflector degradation (see Figure).
The five material types to be studied in the RAISELIFE project will be extensively tested under accelerated aging in climate chambers, relevant outdoor environments, accelerated outdoor tests under elevated solar flux, and in-service in commercial power plants. The appearing degradation mechanisms will be analyzed. The understanding of the failure modes will allow optimizing the material composition towards extended lifetimes. A second generation of materials, produced by the four involved material developer institutes, will be subjected to the same accelerated aging testing program to quantify the lifetime improvement. Finally, the economic impact of the improved RAISELIFE materials on typical CSP plant configurations will be evaluated using plant simulation tools.
So called solar salts are used as an energy storage media and heat transfer fluid in CSP plants. Fraunhofer IWM will contribute to the project by conducting complex corrosion tests of relevant metallic materials in contact with hot salt melts. Therefore special test setups will be used to simulate the corrosion considering the current of the salt that is flowing through the pipes. Stress corrosion tests will be performed by slow strain rate testing (SSRT) in a specialized tensile testing machine equipped with a high-temperature salt tank.
The project was officially launched in Brussels on the 6th and 7th of April 2016 in a kick- off meeting which was attended by all project partners and by the officer from the European Commission and is scheduled for a duration of 48 months. This first meeting served to discuss the organizational structure of the project and the technical content, to decide on matters relating to the dissemination of results, and to plan the activities to be performed in the next 6 months.