TY - CHAP A1 - Schulte, Jonas A1 - Schwager, Christian A1 - Noureldin, Kareem A1 - May, Martin A1 - Teixeira Boura, Cristiano José A1 - Herrmann, Ulf T1 - Gradient controlled startup procedure of a molten-salt power-to-heat energy storage plant based on dynamic process simulation T2 - SolarPACES: Solar Power & Chemical Energy Systems N2 - The integration of high temperature thermal energy storages into existing conventional power plants can help to reduce the CO2 emissions of those plants and lead to lower capital expenditures for building energy storage systems, due to the use of synergy effects [1]. One possibility to implement that, is a molten salt storage system with a powerful power-to-heat unit. This paper presents two possible control concepts for the startup of the charging system of such a facility. The procedures are implemented in a detailed dynamic process model. The performance and safety regarding the film temperatures at heat transmitting surfaces are investigated in the process simulations. To improve the accuracy in predicting the film temperatures, CFD simulations of the electrical heater are carried out and the results are merged with the dynamic model. The results show that both investigated control concepts are safe regarding the temperature limits. The gradient controlled startup performed better than the temperature-controlled startup. Nevertheless, there are several uncertainties that need to be investigated further. KW - Power plants KW - Energy storage KW - Associated liquids Y1 - 2023 SN - 978-0-7354-4623-6 U6 - https://doi.org/10.1063/5.0148741 SN - 1551-7616 (online) SN - 0094-243X (print) N1 - SolarPACES: SOLAR POWER & CHEMICAL ENERGY SYSTEMS: 27th International Conference on Concentrating Solar Power and Chemical Energy Systems, 27 September–1 October 2021, Online IS - 2815 / 1 PB - AIP conference proceedings / American Institute of Physics CY - Melville, NY ER - TY - CHAP A1 - Schwager, Christian A1 - Angele, Florian A1 - Nouri, Bijan A1 - Schwarzbözl, Peter A1 - Teixeira Boura, Cristiano José A1 - Herrmann, Ulf T1 - Impact of DNI forecast quality on performance prediction for a commercial scale solar tower: Application of nowcasting DNI maps to dynamic solar tower simulation T2 - SolarPACES 2022 conference proceedings N2 - Concerning current efforts to improve operational efficiency and to lower overall costs of concentrating solar power (CSP) plants with prediction-based algorithms, this study investigates the quality and uncertainty of nowcasting data regarding the implications for process predictions. DNI (direct normal irradiation) maps from an all-sky imager-based nowcasting system are applied to a dynamic prediction model coupled with ray tracing. The results underline the need for high-resolution DNI maps in order to predict net yield and receiver outlet temperature realistically. Furthermore, based on a statistical uncertainty analysis, a correlation is developed, which allows for predicting the uncertainty of the net power prediction based on the corresponding DNI forecast uncertainty. However, the study reveals significant prediction errors and the demand for further improvement in the accuracy at which local shadings are forecasted. KW - Process prediction KW - DNI forecasting KW - Nowcasting KW - Uncertainty analysis KW - Molten salt receiver system, Y1 - 2024 U6 - https://doi.org/10.52825/solarpaces.v1i.675 SN - 2751-9899 (online) N1 - SolarPACES 2022, 28th International Conference on Concentrating Solar Power and Chemical Energy Systems, 27-30 September, Albuquerque, NM, USA IS - 1 PB - TIB Open Publishing CY - Hannover ER - TY - CHAP A1 - Schwager, Christian A1 - Angele, Florian A1 - Schwarzbözl, Peter A1 - Teixeira Boura, Cristiano José A1 - Herrmann, Ulf T1 - Model predictive assistance for operational decision making in molten salt receiver systems T2 - SolarPACES: Solar Power & Chemical Energy Systems N2 - Despite the challenges of pioneering molten salt towers (MST), it remains the leading technology in central receiver power plants today, thanks to cost effective storage integration and high cost reduction potential. The limited controllability in volatile solar conditions can cause significant losses, which are difficult to estimate without comprehensive modeling [1]. This paper presents a Methodology to generate predictions of the dynamic behavior of the receiver system as part of an operating assistance system (OAS). Based on this, it delivers proposals if and when to drain and refill the receiver during a cloudy period in order maximize the net yield and quantifies the amount of net electricity gained by this. After prior analysis with a detailed dynamic two-phase model of the entire receiver system, two different reduced modeling approaches where developed and implemented in the OAS. A tailored decision algorithm utilizes both models to deliver the desired predictions efficiently and with appropriate accuracy. KW - Power plants KW - Associated liquids KW - Decision theory KW - Electrochemistry Y1 - 2023 SN - 978-0-7354-4623-6 U6 - https://doi.org/10.1063/5.0151514 SN - 1551-7616 (online) SN - 0094-243X (print) N1 - SolarPACES: SOLAR POWER & CHEMICAL ENERGY SYSTEMS: 27th International Conference on Concentrating Solar Power and Chemical Energy Systems, 27 September–1 October 2021, Online IS - 2815 / 1 PB - AIP conference proceedings / American Institute of Physics CY - Melville, NY ER - TY - JOUR A1 - Schwager, Christian A1 - Flesch, Robert A1 - Schwarzbözl, Peter A1 - Herrmann, Ulf A1 - Teixeira Boura, Cristiano José T1 - Advanced two phase flow model for transient molten salt receiver system simulation JF - Solar Energy N2 - In order to realistically predict and optimize the actual performance of a concentrating solar power (CSP) plant sophisticated simulation models and methods are required. This paper presents a detailed dynamic simulation model for a Molten Salt Solar Tower (MST) system, which is capable of simulating transient operation including detailed startup and shutdown procedures including drainage and refill. For appropriate representation of the transient behavior of the receiver as well as replication of local bulk and surface temperatures a discretized receiver model based on a novel homogeneous two-phase (2P) flow modelling approach is implemented in Modelica Dymola®. This allows for reasonable representation of the very different hydraulic and thermal properties of molten salt versus air as well as the transition between both. This dynamic 2P receiver model is embedded in a comprehensive one-dimensional model of a commercial scale MST system and coupled with a transient receiver flux density distribution from raytracing based heliostat field simulation. This enables for detailed process prediction with reasonable computational effort, while providing data such as local salt film and wall temperatures, realistic control behavior as well as net performance of the overall system. Besides a model description, this paper presents some results of a validation as well as the simulation of a complete startup procedure. Finally, a study on numerical simulation performance and grid dependencies is presented and discussed. KW - Molten salt solar tower KW - Molten salt receiver system KW - Dynamic simulation KW - Two-phase modelling KW - Transient flux distribution Y1 - 2022 U6 - https://doi.org/10.1016/j.solener.2021.12.065 SN - 0038-092X (print) SN - 1471-1257 (online) VL - 232 SP - 362 EP - 375 PB - Elsevier CY - Amsterdam ER - TY - BOOK A1 - Schwarzer, Klemens T1 - Verfahren zur Abscheidung von Spalt- und Aktivierungsprodukten aus einer Gasatmosphäre und Vorrichtung zur Durchführung des Verfahrens ; Patentschrift DE000002755881C3 ; Veröffentlichungstag: 11.6.81 / Patentinhaber: Kernforschungsanlage Jülich GmbH Y1 - 1981 N1 - Volltext über Datenbank: http://depatisnet.dpma.de/ PB - Deutsches Patentamt CY - München ER - TY - JOUR A1 - Schwarzer, Klemens T1 - Anwendung solarer Hochtemperaturwärme am Beispiel eines Solarkochers JF - Wege in die Solargesellschaft 4 : Dokumentation zur Vortragsreihe an der Fachhochschule Darmstadt in Zusammenarbeit mit dem IKU-Institut für kommunale Wirtschaft und Umweltplanung im Sommersemester 1993 / [Hrsg.: Projektgruppe Solarenergie an der Fachhochschule Darmstadt ; IKU-Inst. für Kommunale Wirtschaft u. Umweltplanung. Red.: Helmut C. Büscher] Y1 - 1993 N1 - Ringvorlesung Wege in die Solargesellschaft <4, 1993, Darmstadt> SP - 13 EP - 24 PB - FHD CY - Darmstadt ER - TY - BOOK A1 - Schwarzer, Klemens T1 - Gutachten zu möglichen Strahlenexpositionen durch äußere radioaktive Kontaminationen an Transportbehältern oder Transportwaggons beim Transport von abgebrannten Brennelementen nach Frankreich / Auftraggeber: Staatsanwaltschaft Hanau Y1 - 1999 PB - IBEU, Ing.-Büro für Energie- u. Umweltechnik CY - Jülich ER - TY - BOOK A1 - Schwarzer, Klemens T1 - Radionuklidtransport im Boden. - Als Ms. gedr. Y1 - 1979 N1 - (Berichte der Kernforschungsanlage Jülich ; 1572). - Zugl.: Aachen, Techn. Hochsch., Fak. für Maschinenwesen, Diss., 1979 PB - Zentralbibliothek der Kernforschungsanlage Jülich CY - Jülich ER - TY - BOOK A1 - Schwarzer, Klemens T1 - Lacasa : Einsatz von MATLAB-Simulink zur energetischen Analyse und Optimierung von Alt- und Neubauten inklusive Heizungs-, Lüftungs- und Klimatechnik / Hrsg.: FIA-Projekt, Forschungs-Informations-Austausch im Fachinstitut Gebäude-Klima e.V. Projekt: Solar-Institut Jülich an der Fachhochschule Aachen Y1 - 2004 SN - 3-938210-07-9 PB - FIA-Projekt im Fachinst. Gebäude-Klima CY - Bietigheim-Bissingen ER - TY - BOOK A1 - Schwarzer, Klemens A1 - Altes, Jürgen T1 - Zum Störungsverhalten des HTR 500 : eine Trendanalyse ; [Report] / von J. Altes ... K. Schwarzer ... - (Spezielle Berichte der Kernforschungsanlage Jülich ; 220) Y1 - 1983 N1 - Überarb. Fassung des internat. Berichtes KFA-ISF-IB-3/83. - Erg.-Bd. u. d. T.: Sicherheitstechnische Untersuchungen zum Störfallverhalten des HTR-500 PB - Zentralbibliothek der Kernforschungsanlage CY - Jülich ER -