@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{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{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} } @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} } @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} } @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} } @inproceedings{SchwarzerWiedenfeldBansaletal.1991, author = {Schwarzer, Klemens and Wiedenfeld, M. and Bansal, Narenda K. and Ertl, Karl-Heinz}, title = {A novel solar sterilization and water destillation system : experiment and thermodynamic analysis}, 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. 2,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. 2,II}, publisher = {Pergamon Pr.}, address = {Oxford}, isbn = {0-08-041690-x}, pages = {2276 -- 2281}, year = {1991}, language = {en} } @inproceedings{SpaeteHafnerSchwarzer2000, author = {Sp{\"a}te, Frank and Hafner, B. and Schwarzer, Klemens}, title = {A system for solar process heat for decentralized applications in developing countries}, series = {ISES 1999 Solar World Congress, Jerusalem, Israel, July 4-9, 1999 : conference proceedings / ed. Gershon Grossman. Vol. 3}, booktitle = {ISES 1999 Solar World Congress, Jerusalem, Israel, July 4-9, 1999 : conference proceedings / ed. Gershon Grossman. Vol. 3}, publisher = {Elsevier}, address = {Oxford}, isbn = {0-080-043895-4}, pages = {236 -- 291}, year = {2000}, language = {en} } @inproceedings{TeixeiraBouraEcksteinFelinksetal.2011, author = {Teixeira Boura, Cristiano Jos{\´e} and Eckstein, J. and Felinks, J. and G{\"o}ttsche, Joachim and Hoffschmidt, Bernhard and Schmitz, S.}, title = {3-D CFD simulation of an air-sand heat exchanger}, series = {SolarPACES 2011 : concentrating solar power and chemical energy systems : 20 - 23 September, 2011, Granada, Spain}, booktitle = {SolarPACES 2011 : concentrating solar power and chemical energy systems : 20 - 23 September, 2011, Granada, Spain}, address = {Granada}, pages = {1 CD-ROM}, year = {2011}, language = {en} } @inproceedings{TeixeiraBouraNiederwestbergMcLeodetal.2016, author = {Teixeira Boura, Cristiano Jos{\´e} and Niederwestberg, Stefan and McLeod, Jacqueline and Herrmann, Ulf and Hoffschmidt, Bernhard}, title = {Development of heat exchanger for high temperature energy storage with bulk materials}, series = {AIP Conference Proceedings}, volume = {1734}, booktitle = {AIP Conference Proceedings}, number = {1}, doi = {10.1063/1.4949106}, pages = {050008-1 -- 050008-7}, year = {2016}, language = {en} } @article{VelrajSeenirajHafneretal.1999, author = {Velraj, R. and Seeniraj, R. V. and Hafner, B. and Faber, Christian and Schwarzer, Klemens}, title = {Heat transfer enhancement in a latent heat storage system}, series = {Solar energy. Vol. 65, iss. 3}, journal = {Solar energy. Vol. 65, iss. 3}, issn = {0038-092X}, pages = {171 -- 180}, year = {1999}, language = {en} } @article{VieiradaSilvaSchwarzerHoffschmidtetal.2013, author = {Vieira da Silva, Maria Eugenia and Schwarzer, Klemens and Hoffschmidt, Bernhard and Pinheiro Rodrigues, Frederico and Schwarzer, Tarik and Costa Rocha, Paulo Alexandre}, title = {Mass transfer correlation for evaporation-condensation thermal process in the range of 70 °C-95 °C}, series = {Renewable energy}, volume = {Vol. 53}, journal = {Renewable energy}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1879-0682 (E-Journal); 0960-1481 (Print)}, pages = {174 -- 179}, year = {2013}, language = {en} } @inproceedings{WarerkarSchmitzGoettscheetal.2008, author = {Warerkar, S. and Schmitz, S. and G{\"o}ttsche, Joachim and Hoffschmidt, Bernhard and Tamme, R.}, title = {Performance analysis of an air-sand heat exchanger prototype for high-temperature storage}, 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 = {2215 -- 2222}, year = {2008}, language = {en} } @inproceedings{WarerkarSchmitzGoettscheetal.2009, author = {Warerkar, Shashikant and Schmitz, Stefan and G{\"o}ttsche, Joachim and Hoffschmidt, Bernhard and Reißel, Martin and Tamme, Rainer}, title = {Air-sand heat exchanger for high-temperature storage}, series = {Proceedings of the ASME 3rd International Conference on Energy Sustainability : July 19 - 23, 2009, San Francisco, California, USA. Vol. 2}, booktitle = {Proceedings of the ASME 3rd International Conference on Energy Sustainability : July 19 - 23, 2009, San Francisco, California, USA. Vol. 2}, publisher = {ASME}, address = {New York, NY}, isbn = {978-0-7918-4890-6}, pages = {655 -- 661}, year = {2009}, language = {en} } @article{WemhoenerHafnerSchwarzer2000, author = {Wemh{\"o}ner, Carsten and Hafner, Bernd and Schwarzer, Klemens}, title = {Simulation of solar thermal systems with CARNOT blockset in the environment MATLAB-Simulink}, pages = {1 -- 6}, year = {2000}, language = {en} } @article{WoliszSchuetzBlankeetal.2017, author = {Wolisz, Henryk and Sch{\"u}tz, Thomas and Blanke, Tobias and Hagenkamp, Markus and Kohrn, Markus and Wesseling, Mark and M{\"u}ller, Dirk}, title = {Cost optimal sizing of smart buildings' energy system components considering changing end-consumer electricity markets}, series = {Energy}, volume = {137}, journal = {Energy}, publisher = {Elsevier}, address = {Amsterdam}, doi = {10.1016/j.energy.2017.06.025}, pages = {715 -- 728}, year = {2017}, language = {en} } @inproceedings{ZahraPhaniSrujanCaminosetal.2022, author = {Zahra, Mahdi and Phani Srujan, Merige and Caminos, Ricardo Alexander Chico and Schmitz, Pascal and Herrmann, Ulf and Teixeira Boura, Cristiano Jos{\´e} and Schmitz, Mark and Gielen, Hans and Gedle, Yibekal and Dersch, J{\"u}rgen}, title = {Modeling the thermal behavior of solar salt in electrical resistance heaters for the application in PV-CSP hybrid power plants}, series = {SOLARPACES 2020}, booktitle = {SOLARPACES 2020}, number = {2445 / 1}, publisher = {AIP conference proceedings / American Institute of Physics}, address = {Melville, NY}, isbn = {978-0-7354-4195-8}, issn = {1551-7616 (online)}, doi = {10.1063/5.0086268}, pages = {9 Seiten}, year = {2022}, abstract = {Concentrated Solar Power (CSP) systems are able to store energy cost-effectively in their integrated thermal energy storage (TES). By intelligently combining Photovoltaics (PV) systems with CSP, a further cost reduction of solar power plants is expected, as well as an increase in dispatchability and flexibility of power generation. PV-powered Resistance Heaters (RH) can be deployed to raise the temperature of the molten salt hot storage from 385 °C up to 565 °C in a Parabolic Trough Collector (PTC) plant. To avoid freezing and decomposition of molten salt, the temperature distribution in the electrical resistance heater is investigated in the present study. For this purpose, a RH has been modeled and CFD simulations have been performed. The simulation results show that the hottest regions occur on the electric rod surface behind the last baffle. A technical optimization was performed by adjusting three parameters: Shell-baffle clearance, electric rod-baffle clearance and number of baffles. After the technical optimization was carried out, the temperature difference between the maximum temperature and the average outlet temperature of the salt is within the acceptable limits, thus critical salt decomposition has been avoided. Additionally, the CFD simulations results were analyzed and compared with results obtained with a one-dimensional model in Modelica.}, language = {en} } @inproceedings{ZiolkoSchmitzSattleretal.2010, author = {Ziolko, C. and Schmitz, M. and Sattler, Johannes, Christoph and Khedim, Ahmed and Hoffschmidt, Bernhard}, title = {AlSol - the open volumetric receiver technology moves to Africa}, 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 = {93 -- 94}, year = {2010}, language = {en} }