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%0 Thesis
%A Fritsch, Andreas
%T Potenzialanalyse von Solarturmkraftwerken mit Flüssigmetallen als Wärmeträgermedium
%I RWTH Aachen University
%V Dissertation
%C Berlin
%M RWTH-2018-226448
%@ 978-3-8325-4724-0
%P 1 Online-Ressource (xx, 244 Seiten) : Illustrationen, Diagramme
%D 2018
%Z Veröffentlicht auf dem Publikationsserver der RWTH Aachen University
%Z Dissertation, RWTH Aachen University, 2018
%X Today solar power plants with central receiver technology often use molten nitrate salts like Hitec or Solar Salt as heat transfer fluid and storage medium. Due to their high heat capacity and the low cost these are well suited for thermal energy storage. Nevertheless, these salts also inherit disadvantages, such as high melting points above 220°C demanding high energy for trace heating. The upper temperature limit of Solar Salt is at 565°C. Therefore, high temperature power conversion cycles with high efficiency are unfeasible. Additionally, its high density results in a high pressure drop in the riser, leading to additional parasitic losses. In plants operating with Solar Salt, freeze events and corrosion problems occur. Moreover, high pressure drops have to be accepted in the absorber tubes to achieve a reasonable heat transfer. In all the mentioned points liquid metals possess advantages compared to molten salts. Sodium is the most often used liquid metal in research and industry and was already tested at the solar test center PSA in Almería in Spain. The only disadvantage of sodium - its reactivity with water and oxygen - was demonstrated in a sodium fire and the eventual destruction of the test center in summer 1986. During the last 30 years measurement techniques and safety precautions were developed to avoid such accidents. The present work analyses the properties of liquid metals in detail and compares them with Solar Salt. The custom-built design and simulation tool for tubular receivers ASTRID makes a precise thermohydraulic calculation possible. The assessment of the liquid metal concepts is based on annual yields and LCOE calculations, which are compared to a reference system with Solar Salt. All concepts with liquid metals use electromagnetic pumps. After the solar heating in the receiver the heat is transferred from sodium to Solar Salt in a heat exchanger and then stored in a two-tank storage. Both the reference concept and the liquid metal concepts use the same power block and the same temperatures in storage and turbine. The results indicate a potential to reduction in LCOE with sodium of up to 16 
%F PUB:(DE-HGF)11 ; PUB:(DE-HGF)3
%9 Dissertation / PhD ThesisBook
%R 10.18154/RWTH-2018-226448
%U https://publications.rwth-aachen.de/record/729482