@inproceedings{SchwagerAngeleNourietal.2022, author = {Schwager, Christian and Angele, Florian and Nouri, Bijan and Schwarzb{\"o}zl, Peter and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf}, title = {Impact of DNI forecast quality on performance prediction for a commercial scale solar tower: Application of nowcasting DNI maps to dynamic solar tower simulation}, series = {SolarPACES conference proceedings}, booktitle = {SolarPACES conference proceedings}, number = {Vol. 1}, publisher = {TIB Open Publishing}, address = {Hannover}, issn = {2751-9899 (online)}, doi = {10.52825/solarpaces.v1i.675}, pages = {9 Seiten}, year = {2022}, abstract = {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.}, language = {en} } @inproceedings{SchwagerAngeleSchwarzboezletal.2023, author = {Schwager, Christian and Angele, Florian and Schwarzb{\"o}zl, Peter and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf}, title = {Model predictive assistance for operational decision making in molten salt receiver systems}, series = {SolarPACES: Solar Power \& Chemical Energy Systems}, booktitle = {SolarPACES: Solar Power \& Chemical Energy Systems}, number = {2815 / 1}, publisher = {AIP conference proceedings / American Institute of Physics}, address = {Melville, NY}, isbn = {978-0-7354-4623-6}, issn = {1551-7616 (online)}, doi = {10.1063/5.0151514}, pages = {8 Seiten}, year = {2023}, abstract = {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.}, language = {en} } @article{SchwagerFleschSchwarzboezletal.2022, author = {Schwager, Christian and Flesch, Robert and Schwarzb{\"o}zl, Peter and Herrmann, Ulf and Teixeira Boura, Cristiano Jos{\´e}}, title = {Advanced two phase flow model for transient molten salt receiver system simulation}, series = {Solar Energy}, volume = {232}, journal = {Solar Energy}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0038-092X (print)}, doi = {10.1016/j.solener.2021.12.065}, pages = {362 -- 375}, year = {2022}, abstract = {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.}, language = {en} } @inproceedings{SchwagerTeixeiraBouraFleschetal.2019, author = {Schwager, Christian and Teixeira Boura, Cristiano Jos{\´e} and Flesch, Robert and Alexopoulos, Spiros and Herrmann, Ulf}, title = {Improved efficiency prediction of a molten salt receiver based on dynamic cloud passage simulation}, series = {AIP Conference Proceedings}, volume = {2126}, booktitle = {AIP Conference Proceedings}, number = {1}, isbn = {978-0-7354-1866-0}, doi = {10.1063/1.5117566}, pages = {030054-1 -- 030054-8}, year = {2019}, language = {en} } @inproceedings{SchwarzboezlPompKolletal.2010, author = {Schwarzb{\"o}zl, Peter and Pomp, Stefan and Koll, Gerrit and Hennecke, Klaus and Hartz, Thomas and Schmitz, Mark and Hoffschmidt, Bernhard}, title = {The solar tower J{\"u}lich - first operational experiences and test results}, series = {SolarPACES 2010 : the CSP Conference: electricity, fuels and clean water from concentrated solar energy ; 21 to 24 September 2010, Perpignan, France}, booktitle = {SolarPACES 2010 : the CSP Conference: electricity, fuels and clean water from concentrated solar energy ; 21 to 24 September 2010, Perpignan, France}, publisher = {Soc. OSC}, address = {Saint Maur}, pages = {8 -- 9}, year = {2010}, language = {en} } @inproceedings{Schwarzer1992, author = {Schwarzer, Klemens}, title = {A new kind of efficient solar cookers with and without temporary heat storage}, series = {Advances in solar cooking : proceedings of the First World Conference on Solar Cooking, Stockton, California, USA, June 19 - 20, 1992 / ed. by Edwin Pejack}, booktitle = {Advances in solar cooking : proceedings of the First World Conference on Solar Cooking, Stockton, California, USA, June 19 - 20, 1992 / ed. by Edwin Pejack}, publisher = {Solar Box Cookers International}, address = {Sacramento, Calif.}, pages = {107 -- 112}, year = {1992}, language = {en} } @inproceedings{Schwarzer2006, author = {Schwarzer, Klemens}, title = {Solarthermisches Entsalzungssystem mit W{\"a}rmer{\"u}ckgewinnung - Erste Feldtestergebnisse}, series = {16. Symposium Thermische Solarenergie : 17. bis 19. Mai 2006, Kloster Banz, Bad Staffelstein}, booktitle = {16. Symposium Thermische Solarenergie : 17. bis 19. Mai 2006, Kloster Banz, Bad Staffelstein}, publisher = {Ostbayer. Technologie-Transfer-Inst.}, address = {Regensburg}, isbn = {3-934681-45-X}, pages = {173 -- 178}, year = {2006}, language = {de} } @inproceedings{Schwarzer2008, author = {Schwarzer, Klemens}, title = {Desalination systems with renewable energies}, series = {DME Seminar Desalination and Renewable Energies : June 19 and 20 2008, Solar Institut J{\"u}lich / Deutsche Meerwasserentsalzung e.V.}, booktitle = {DME Seminar Desalination and Renewable Energies : June 19 and 20 2008, Solar Institut J{\"u}lich / Deutsche Meerwasserentsalzung e.V.}, publisher = {DME}, address = {Duisburg}, isbn = {978-3-86861-017-8}, pages = {219 Bl. in getr. Z{\"a}hlung : zahlr. Ill. und graph. Darst., Kt.}, year = {2008}, language = {en} } @inproceedings{SchwarzerBiegerRicking1990, author = {Schwarzer, Klemens and Bieger, W. and Ricking, N.}, title = {Entwicklung und Erprobung eines solaren Kochers mit tempor{\"a}rem Speicher}, series = {Rationelle Energieverwendung und Nutzung erneuerbarer Energiequellen im regionalen und kommunalen Bereich : : welchen Beitrag k{\"o}nnen sie zur Abwehr der Klimabedrohung leisten?; Frankfurt, 9. - 12. Oktober 1990; [Tagungsbericht] / 7. Internationales Sonnenforum. [Veranst.: Deutsche Gesellschaft f{\"u}r Sonnenenergie e.V., Deutsche Sektion der ISES. Red.: A. Hohmann; H. H. Hohmann]. Bd. 2.}, booktitle = {Rationelle Energieverwendung und Nutzung erneuerbarer Energiequellen im regionalen und kommunalen Bereich : : welchen Beitrag k{\"o}nnen sie zur Abwehr der Klimabedrohung leisten?; Frankfurt, 9. - 12. Oktober 1990; [Tagungsbericht] / 7. Internationales Sonnenforum. [Veranst.: Deutsche Gesellschaft f{\"u}r Sonnenenergie e.V., Deutsche Sektion der ISES. Red.: A. Hohmann; H. H. Hohmann]. Bd. 2.}, publisher = {DGS-Sonnenenergie-Verl.}, address = {M{\"u}nchen}, pages = {1002 -- 1007}, year = {1990}, language = {de} } @inproceedings{SchwarzerBiegerRickingetal.1991, author = {Schwarzer, Klemens and Bieger, W. and Ricking, N. and Bansal, Narenda K.}, title = {Solar cooker with a rock bed cum oil storage}, series = {1991 Solar World Congress : : proceedings of the Biennial Congress of the International Solar Energy Society, Denver, Colorado, USA, 19 - 23 August 1991 / ed. by M. E. Arden. Bd. 3,II}, booktitle = {1991 Solar World Congress : : proceedings of the Biennial Congress of the International Solar Energy Society, Denver, Colorado, USA, 19 - 23 August 1991 / ed. by M. E. Arden. Bd. 3,II}, publisher = {Pergamon Pr.}, address = {Oxford}, isbn = {0-08-041690-x}, pages = {3751 -- 3756}, year = {1991}, language = {en} } @inproceedings{SchwarzerFaberMelissetal.1993, author = {Schwarzer, Klemens and Faber, Christian and Meliß, Michael and Sp{\"a}te, F.}, title = {Solar-Institut J{\"u}lich (SIJ), Fachhochschule Aachen, Division J{\"u}lich Germany}, series = {Harmony with nature : proceedings / ISES Solar World Congress, Budapest 1993. International Solar Energy Society, Hungarian Section (H-ISES); Hungarian Solar Energy Society (HSES). Vol. 1: Energy policy, environment, education}, booktitle = {Harmony with nature : proceedings / ISES Solar World Congress, Budapest 1993. International Solar Energy Society, Hungarian Section (H-ISES); Hungarian Solar Energy Society (HSES). Vol. 1: Energy policy, environment, education}, publisher = {Hungarian Energy Society}, address = {Budapest}, pages = {349 -- 354}, year = {1993}, language = {en} } @techreport{SchwarzerGoettscheJellinghaus2006, author = {Schwarzer, Klemens and G{\"o}ttsche, Joachim and Jellinghaus, Sabine}, title = {Farblichtstudie : Beleuchtung mit gesteuertem Farblicht - Untersuchung und Optimierung von Systemen zur Farblichtsteuerung : Abschlussbericht M{\"a}rz 2006}, pages = {39 S.}, year = {2006}, language = {de} } @inproceedings{SchwarzerHafnerMeeretal.1993, author = {Schwarzer, Klemens and Hafner, B. and Meer, A. von and Krings, T.}, title = {Simulation and dimensioning program for solar cookers with temporal heat storage and comparison with measurements}, series = {Harmony with nature : : proceedings / ISES Solar World Congress, Budapest 1993. International Solar Energy Society, Hungarian Section (H-ISES); Hungarian Solar Energy Society (HSES). Bd 5: Active systems}, booktitle = {Harmony with nature : : proceedings / ISES Solar World Congress, Budapest 1993. International Solar Energy Society, Hungarian Section (H-ISES); Hungarian Solar Energy Society (HSES). Bd 5: Active systems}, publisher = {Hungarian Energy Society}, address = {Budapest}, pages = {473 -- 478}, year = {1993}, language = {en} } @techreport{SchwarzerHafner1999, author = {Schwarzer, Klemens and Hafner, Bernd}, title = {Aufbau und Erprobung eines Latentw{\"a}rmespeichers f{\"u}r den Einsatz in Raumheizungssystemen. Abschlussbericht BMBF 1700297}, pages = {64 S.}, year = {1999}, language = {de} } @techreport{SchwarzerHoeller1998, author = {Schwarzer, Klemens and H{\"o}ller, Robert}, title = {EOS Ertragsverbesserung und Optimierung von Energie Systemen. Abschlussbericht BMBF 1700796}, pages = {35 S.}, year = {1998}, language = {de} } @inproceedings{SchwarzerKringsFaberetal.1998, author = {Schwarzer, Klemens and Krings, T. and Faber, Christian and Hafner, B.}, title = {Erfahrungen mit Solarkochern verschiedener Gr{\"o}ße f{\"u}r Familien und Institutionen}, series = {Deutschlands Weg in eine solare Zukunft : Tagungsband; 26. - 30. Juni 1998 Fachhochschule K{\"o}ln / 11. Internationales Sonnenforum}, booktitle = {Deutschlands Weg in eine solare Zukunft : Tagungsband; 26. - 30. Juni 1998 Fachhochschule K{\"o}ln / 11. Internationales Sonnenforum}, publisher = {Solar Promotion}, address = {M{\"u}nchen}, organization = {Deutsche Gesellschaft f{\"u}r Sonnenenergie}, pages = {801 -- 809}, year = {1998}, language = {de} } @inproceedings{SchwarzerKrokerRusack2008, author = {Schwarzer, Klemens and Kroker, Jan and Rusack, Markus}, title = {Technical improvement of a small modular parabolic trough collector}, series = {EuroSun 2008 : 1st International Conference on Solar Heating, Cooling and Buildings ; 7th - 10th October 2008, Lisbon, Portugal : key lectures / ISES, International Solar Energy Society. Vol. 1}, booktitle = {EuroSun 2008 : 1st International Conference on Solar Heating, Cooling and Buildings ; 7th - 10th October 2008, Lisbon, Portugal : key lectures / ISES, International Solar Energy Society. Vol. 1}, publisher = {Sociedade Portuguesa De Energia Solar (SPES)}, address = {Lissabon}, isbn = {978-1-61782-228-5}, pages = {1395 -- 1402}, year = {2008}, language = {en} } @inproceedings{SchwarzerSchwarzer2009, author = {Schwarzer, Klemens and Schwarzer, Tarik}, title = {Stand und Entwicklung der Meerwasserentsalzung}, series = {Neue Herausforderungen und Chancen in der Wasserversorgung : Seminar des Fachgebiets Wasserversorgung und Grundwasserschutz im Rahmen des 1. Darmst{\"a}dter Ingenieurkongresses Bau und Umwelt am 14. und 15.09.2009. Schriftenreihe WAR. 205}, booktitle = {Neue Herausforderungen und Chancen in der Wasserversorgung : Seminar des Fachgebiets Wasserversorgung und Grundwasserschutz im Rahmen des 1. Darmst{\"a}dter Ingenieurkongresses Bau und Umwelt am 14. und 15.09.2009. Schriftenreihe WAR. 205}, publisher = {Inst. WAR}, address = {Darmstadt}, isbn = {978-3-940897-01-5}, pages = {99 -- 120}, year = {2009}, language = {de} } @article{SchwarzerVieiradaSilvaSchwarzer2011, author = {Schwarzer, Klemens and Vieira da Silva, Maria Eugenia and Schwarzer, Tarik}, title = {Field results in Namibia and Brazil of the new solar desalination system for decentralised drinking water production}, series = {Desalination and water treatment. Vol. 31 (2011), iss. 1-3: selected papers presented at EuroMed 2010 — Desalination for Clean Water and Energy: Cooperation among Mediterranean Countries of Europe and MENA Region, 3-7 October 2010, Tel Aviv, Israel}, journal = {Desalination and water treatment. Vol. 31 (2011), iss. 1-3: selected papers presented at EuroMed 2010 — Desalination for Clean Water and Energy: Cooperation among Mediterranean Countries of Europe and MENA Region, 3-7 October 2010, Tel Aviv, Israel}, pages = {379 -- 386}, year = {2011}, language = {en} } @inproceedings{SchwarzerVieiraMuelleretal.2003, author = {Schwarzer, Klemens and Vieira, Maria Eugenia and M{\"u}ller, Christoph and Lehmann, Harry and Coutinho, Lecimara}, title = {Modular solar thermal desalination system with flat plate collector}, series = {RIO 3 - World Climate \& Energy Event : proceedings of the international conference held in Rio de Janeiro, Brazil, 1 -5 december 2003 / chief-ed.: Stefan Krauter ...}, booktitle = {RIO 3 - World Climate \& Energy Event : proceedings of the international conference held in Rio de Janeiro, Brazil, 1 -5 december 2003 / chief-ed.: Stefan Krauter ...}, publisher = {Krauter}, address = {Rio de Janeiro}, isbn = {85-902710-2-1}, pages = {281 -- 286}, year = {2003}, language = {en} }