@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{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} } @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{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} } @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{SchulzeBuxlohGrossUlbrich2021, author = {Schulze-Buxloh, Lina and Groß, Rolf Fritz and Ulbrich, Michelle}, title = {Digital planning using building information modelling and virtual reality: new approach for students' remote practical training under lockdown conditions in the course of smart building engineering}, series = {Proceedings of International Conference on Education in Mathematics, Science and Technology 2021}, booktitle = {Proceedings of International Conference on Education in Mathematics, Science and Technology 2021}, publisher = {ISTES Organization}, address = {San Antonio, TX}, isbn = {978-1-952092-17-6}, pages = {118 -- 123}, year = {2021}, abstract = {The worldwide Corona pandemic has severely restricted student projects in the higher semesters of engineering courses. In order not to delay the graduation, a new concept had to be developed for projects under lockdown conditions. Therefore, unused rooms at the university should be digitally recorded in order to develop a new usage concept as laboratory rooms. An inventory of the actual state of the rooms was done first by taking photos and listing up all flaws and peculiarities. After that, a digital site measuring was done with a 360° laser scanner and these recorded scans were linked to a coherent point cloud and transferred to a software for planning technical building services and supporting Building Information Modelling (BIM). In order to better illustrate the difference between the actual and target state, two virtual reality models were created for realistic demonstration. During the project, the students had to go through the entire digital planning phases. Technical specifications had to be complied with, as well as documentation, time planning and cost estimate. This project turned out to be an excellent alternative to on-site practical training under lockdown conditions and increased the students' motivation to deal with complex technical questions.}, language = {en} } @inproceedings{SchulzeBuxlohGross2021, author = {Schulze-Buxloh, Lina and Groß, Rolf Fritz}, title = {Miniature urban farming plant: a complex educational "Toy" for engineering students}, series = {The Future of Education 11th Edition 2021}, booktitle = {The Future of Education 11th Edition 2021}, pages = {4 Seiten}, year = {2021}, abstract = {Urban farming is an innovative and sustainable way of food production and is becoming more and more important in smart city and quarter concepts. It also enables the production of certain foods in places where they usually dare not produced, such as production of fish or shrimps in large cities far away from the coast. Unfortunately, it is not always possible to show students such concepts and systems in real life as part of courses: visits of such industry plants are sometimes not possible because of distance or are permitted by the operator for hygienic reasons. In order to give the students the opportunity of getting into contact with such an urban farming system and its complex operation, an industrial urban farming plant was set up on a significantly smaller scale. Therefore, all needed technical components like water aeriation, biological and mechanical filtration or water circulation have been replaced either by aquarium components or by self-designed parts also using a 3D-printer. Students from different courses like mechanical engineering, smart building engineering, biology, electrical engineering, automation technology and civil engineering were involved in this project. This "miniature industrial plant" was also able to start operation and has now been running for two years successfully. Due to Corona pandemic, home office and remote online lectures, the automation of this miniature plant should be brought to a higher level in future for providing a good control over the system and water quality remotely. The aim of giving the student a chance to get to know the operation of an urban farming plant was very well achieved and the students had lots of fun in "playing" and learning with it in a realistic way.}, language = {en} } @inproceedings{SchulzeBuxlohGross2021, author = {Schulze-Buxloh, Lina and Groß, Rolf Fritz}, title = {Interdisciplinary Course Smart Building Engineering: A new approach of teaching freshmen in remote teamwork project under pandemic restrictions}, series = {New Perspectives in Science Education -International Conference (virtual event, 18-19 March 2021)}, booktitle = {New Perspectives in Science Education -International Conference (virtual event, 18-19 March 2021)}, publisher = {Filodiritto}, address = {Bologna}, pages = {4 Seiten}, year = {2021}, abstract = {In the context of the Corona pandemic and its impact on teaching like digital lectures and exercises a new concept especially for freshmen in demanding courses of Smart Building Engineering became necessary. As there were hardly any face-to-face events at the university, the new teaching concept should enable a good start into engineering studies under pandemic conditions anyway and should also replace the written exam at the end. The students should become active themselves in small teams instead of listening passively to a lecture broadcast online with almost no personal contact. For this purpose, a role play was developed in which the freshmen had to work out a complete solution to the realistic problem of designing, construction planning and implementing a small guesthouse. Each student of the team had to take a certain role like architect, site manager, BIM-manager, electrician and the technitian for HVAC installations. Technical specifications must be complied with, as well as documentation, time planning and cost estimate. The final project folder had to contain technical documents like circuit diagrams for electrical components, circuit diagrams for water and heating, design calculations and components lists. On the other hand construction schedule, construction implementation plan, documentation of the construction progress and minutes of meetings between the various trades had to be submitted as well. In addition to the project folder, a model of the construction project must also be created either as a handmade model or as a digital 3D-model using Computer-aided design (CAD) software. The first steps in the field of Building information modelling (BIM) had also been taken by creating a digital model of the building showing the current planning status in real time as a digital twin. This project turned out to be an excellent training of important student competencies like teamwork, communication skills, and self -organisation and also increased motivation to work on complex technical questions. The aim of giving the student a first impression on the challenges and solutions in building projects with many different technical trades and their points of view was very well achieved and should be continued in the future.}, language = {en} } @inproceedings{SchulteSchwagerNoureldinetal.2023, author = {Schulte, Jonas and Schwager, Christian and Noureldin, Kareem and May, Martin and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf}, title = {Gradient controlled startup procedure of a molten-salt power-to-heat energy storage plant based on dynamic process simulation}, 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 = {10.1063/5.0148741}, pages = {9 Seiten}, year = {2023}, abstract = {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.}, language = {en} } @inproceedings{SchulteSchwagerFrantzetal.2022, author = {Schulte, Jonas and Schwager, Christian and Frantz, Cathy and Schloms, Felix and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf}, title = {Control concept for a molten salt receiver in star design: Development, optimization and testing with cloud passage scenarios}, 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.693}, pages = {9 Seiten}, year = {2022}, abstract = {A promising approach to reduce the system costs of molten salt solar receivers is to enable the irradiation of the absorber tubes on both sides. The star design is an innovative receiver design, pursuing this approach. The unconventional design leads to new challenges in controlling the system. This paper presents a control concept for a molten salt receiver system in star design. The control parameters are optimized in a defined test cycle by minimizing a cost function. The control concept is tested in realistic cloud passage scenarios based on real weather data. During these tests, the control system showed no sign of unstable behavior, but to perform sufficiently in every scenario further research and development like integrating Model Predictive Controls (MPCs) need to be done. The presented concept is a starting point to do so.}, language = {en} } @inproceedings{SauerbornLiebenstundRaueetal.2017, author = {Sauerborn, Markus and Liebenstund, Lena and Raue, Markus and Mang, Thomas and Herrmann, Ulf and Dueing, Andreas}, title = {Analytic method for material aging and quality analyzing to forecast long time stability of plastic micro heliostat components}, series = {AIP Conference Proceedings}, volume = {1850}, booktitle = {AIP Conference Proceedings}, number = {1}, doi = {10.1063/1.4984388}, pages = {030045-1 -- 030045-8}, year = {2017}, language = {en} } @inproceedings{SauerbornKlimekHoffschmidtetal.2012, author = {Sauerborn, Markus and Klimek, J. and Hoffschmidt, Bernhard and Essen, H. and Sieger, S. and Biegel, G. and G{\"o}ttsche, Joachim and Hilger, Patrick}, title = {Eurosun 2012 : radar technology for heliostat posititon control}, series = {Eurosun 2012 : Solar energy for a brighter future : conference proceedings : Rijeka, 18.-22.09.2012}, booktitle = {Eurosun 2012 : Solar energy for a brighter future : conference proceedings : Rijeka, 18.-22.09.2012}, address = {Rijeka}, pages = {ID 80}, year = {2012}, language = {en} } @inproceedings{SauerbornHoffschmidtTelleetal.2012, author = {Sauerborn, Markus and Hoffschmidt, Bernhard and Telle, R. and Wagner, M.}, title = {Heatable optical analyse system for high temperature absorbers}, series = {30th ISES Biennial Solar World Congress 2011 : : Kassel, Germany, 28 August - 2 September 2011. Vol. 5}, booktitle = {30th ISES Biennial Solar World Congress 2011 : : Kassel, Germany, 28 August - 2 September 2011. Vol. 5}, publisher = {Curran}, address = {Red Hook, NY}, organization = {International Solar Energy Society}, isbn = {978-1-61839-364-7}, pages = {3852 -- 3860}, year = {2012}, language = {en} } @inproceedings{SauerbornArshadiRohrmoser2012, author = {Sauerborn, Markus and Arshadi, S. and Rohrmoser, R.}, title = {Influence of clouds and aerosols to the haze of the sunshape}, series = {30th ISES Biennial Solar World Congress 2011 : Kassel, Germany, 28 August - 2 September 2011. Vol. 5}, booktitle = {30th ISES Biennial Solar World Congress 2011 : Kassel, Germany, 28 August - 2 September 2011. Vol. 5}, publisher = {Curran}, address = {Red Hook, NY}, organization = {International Solar Energy Society}, pages = {3887 -- 3894}, year = {2012}, language = {en} } @inproceedings{Sauerborn2011, author = {Sauerborn, Markus}, title = {Investigations to the influence of clouds and aerosols to the haze of the sunshape}, 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} } @article{SattlerRoegerSchwarzboezletal.2020, author = {Sattler, Johannes, Christoph and R{\"o}ger, Marc and Schwarzb{\"o}zl, Peter and Buck, Reiner and Macke, Ansgar and Raeder, Christian and G{\"o}ttsche, Joachim}, title = {Review of heliostat calibration and tracking control methods}, series = {Solar Energy}, volume = {207}, journal = {Solar Energy}, publisher = {Elsevier}, address = {Amsterdam}, doi = {10.1016/j.solener.2020.06.030}, pages = {110 -- 132}, year = {2020}, abstract = {Large scale central receiver systems typically deploy between thousands to more than a hundred thousand heliostats. During solar operation, each heliostat is aligned individually in such a way that the overall surface normal bisects the angle between the sun's position and the aim point coordinate on the receiver. Due to various tracking error sources, achieving accurate alignment ≤1 mrad for all the heliostats with respect to the aim points on the receiver without a calibration system can be regarded as unrealistic. Therefore, a calibration system is necessary not only to improve the aiming accuracy for achieving desired flux distributions but also to reduce or eliminate spillage. An overview of current larger-scale central receiver systems (CRS), tracking error sources and the basic requirements of an ideal calibration system is presented. Leading up to the main topic, a description of general and specific terms on the topics heliostat calibration and tracking control clarifies the terminology used in this work. Various figures illustrate the signal flows along various typical components as well as the corresponding monitoring or measuring devices that indicate or measure along the signal (or effect) chain. The numerous calibration systems are described in detail and classified in groups. Two tables allow the juxtaposition of the calibration methods for a better comparison. In an assessment, the advantages and disadvantages of individual calibration methods are presented.}, language = {en} } @inproceedings{SattlerCaminosUerlingsetal.2020, author = {Sattler, Johannes, Christoph and Caminos, Ricardo Alexander Chico and {\"U}rlings, Nicolas and Dutta, Siddharth and Ruiz, Victor and Kalogirou, Soteris and Ktistis, Panayiotis and Agathokleous, Rafaela and Jung, Christian and Alexopoulos, Spiros and Atti, Vikrama Nagababu and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf}, title = {Operational experience and behaviour of a parabolic trough collector system with concrete thermal energy storage for process steam generation in Cyprus}, series = {AIP Conference Proceedings}, booktitle = {AIP Conference Proceedings}, number = {2303}, doi = {10.1063/5.0029278}, pages = {140004-1 -- 140004-10}, year = {2020}, language = {en} } @inproceedings{SattlerAlexopoulosCaminosetal.2019, author = {Sattler, Johannes, Christoph and Alexopoulos, Spiros and Caminos, Ricardo Alexander Chico and Mitchell, John C. and Ruiz, Victor C. and Kalogirou, Soteris and Ktistis, Panayiotis K. and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf}, title = {Dynamic simulation model of a parabolic trough collector system with concrete thermal energy storage for process steam generation}, series = {AIP Conference Proceedings}, volume = {2126}, booktitle = {AIP Conference Proceedings}, issn = {0094243X}, doi = {10.1063/1.5117663}, pages = {150007-1 -- 150007-8}, year = {2019}, language = {en} } @inproceedings{SattlerSchneiderAngeleetal.2022, author = {Sattler, Johannes Christoph and Schneider, Iesse Peer and Angele, Florian and Atti, Vikrama and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf}, title = {Development of heliostat field calibration methods: Theory and experimental test results}, 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.678}, pages = {9 Seiten}, year = {2022}, abstract = {In this work, three patent pending calibration methods for heliostat fields of central receiver systems (CRS) developed by the Solar-Institut J{\"u}lich (SIJ) of the FH Aachen University of Applied Sciences are presented. The calibration methods can either operate in a combined mode or in stand-alone mode. The first calibration method, method A, foresees that a camera matrix is placed into the receiver plane where it is subjected to concentrated solar irradiance during a measurement process. The second calibration method, method B, uses an unmanned aerial vehicle (UAV) such as a quadrocopter to automatically fly into the reflected solar irradiance cross-section of one or more heliostats (two variants of method B were tested). The third calibration method, method C, foresees a stereo central camera or multiple stereo cameras installed e.g. on the solar tower whereby the orientations of the heliostats are calculated from the location detection of spherical red markers attached to the heliostats. The most accurate method is method A which has a mean accuracy of 0.17 mrad. The mean accuracy of method B variant 1 is 1.36 mrad and of variant 2 is 1.73 mrad. Method C has a mean accuracy of 15.07 mrad. For method B there is great potential regarding improving the measurement accuracy. For method C the collected data was not sufficient for determining whether or not there is potential for improving the accuracy.}, language = {en} } @inproceedings{SattlerAttiAlexopoulosetal.2022, author = {Sattler, Johannes Christoph and Atti, Vikrama and Alexopoulos, Spiros and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf and Dutta, Siddharth and Kioutsioukis, Ioannis}, title = {DNI forecast tool for the smart operation of a parabolic trough collector system with concrete thermal energy storage: Theory, results and outlook}, 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.731}, pages = {9 Seiten}, year = {2022}, abstract = {This work presents a basic forecast tool for predicting direct normal irradiance (DNI) in hourly resolution, which the Solar-Institut J{\"u}lich (SIJ) is developing within a research project. The DNI forecast data shall be used for a parabolic trough collector (PTC) system with a concrete thermal energy storage (C-TES) located at the company KEAN Soft Drinks Ltd in Limassol, Cyprus. On a daily basis, 24-hour DNI prediction data in hourly resolution shall be automatically produced using free or very low-cost weather forecast data as input. The purpose of the DNI forecast tool is to automatically transfer the DNI forecast data on a daily basis to a main control unit (MCU). The MCU automatically makes a smart decision on the operation mode of the PTC system such as steam production mode and/or C-TES charging mode. The DNI forecast tool was evaluated using historical data of measured DNI from an on-site weather station, which was compared to the DNI forecast data. The DNI forecast tool was tested using data from 56 days between January and March 2022, which included days with a strong variation in DNI due to cloud passages. For the evaluation of the DNI forecast reliability, three categories were created and the forecast data was sorted accordingly. The result was that the DNI forecast tool has a reliability of 71.4 \% based on the tested days. The result fulfils SIJ's aim to achieve a reliability of around 70 \%, but SIJ aims to still improve the DNI forecast quality.}, language = {en} } @inproceedings{RendonSchwagerGhiasietal.2020, author = {Rendon, Carlos and Schwager, Christian and Ghiasi, Mona and Schmitz, Pascal and Bohang, Fakhri and Caminos, Ricardo Alexander Chico and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf}, title = {Modeling and upscaling of a pilot bayonettube reactor for indirect solar mixed methane reforming}, series = {AIP Conference Proceedings}, booktitle = {AIP Conference Proceedings}, number = {2303}, doi = {10.1063/5.0029974}, pages = {170012-1 -- 170012-9}, year = {2020}, language = {en} } @inproceedings{RendonDieckmannWeidleetal.2018, author = {Rendon, Carlos and Dieckmann, Simon and Weidle, Mathias and Dersch, J{\"u}rgen and Teixeira Boura, Cristiano Jos{\´e} and Polklas, Thomas and Kuschel, Marcus and Herrmann, Ulf}, title = {Retrofitting of existing parabolic trough collector power plants with molten salt tower systems}, series = {AIP Conference Proceedings}, volume = {2033}, booktitle = {AIP Conference Proceedings}, number = {1}, doi = {10.1063/1.5067030}, pages = {030014-1 -- 030014-8}, year = {2018}, language = {en} } @article{ReisgenSchleserAbdurakhmanovetal.2012, author = {Reisgen, Uwe and Schleser, Markus and Abdurakhmanov, Aydemir and Turichin, Gleb and Valdaitseva, Elena and Bach, Friedrich-Wilhelm and Hassel, Thomas and Beniyashi, Alexander}, title = {Investigation of factors influencing the formation of weld defects in non-vacuum electron beam welding}, series = {The Paton welding journal}, volume = {2012}, journal = {The Paton welding journal}, number = {2}, publisher = {Paton Publishing House}, address = {Kiev}, issn = {0957-798X}, pages = {11 -- 18}, year = {2012}, abstract = {The influence of welding condition parameters and properties of material on formation of defects, such as humping and undercuts, in non-vacuum electron beam welding was investigated. The influence of separate welding parameters on the quality of welds was determined.}, language = {en} } @article{RauAlexopoulosBreitbachetal.2014, author = {Rau, Christoph and Alexopoulos, Spiros and Breitbach, Gerd and Hoffschmidt, Bernhard and Latzke, Markus and Sattler, Johannes, Christoph}, title = {Transient simulation of a solar-hybrid tower power plant with open volumetric receiver at the location Barstow}, series = {Energy procedia : proceedings of the SolarPACES 2013 International Conference}, volume = {49}, journal = {Energy procedia : proceedings of the SolarPACES 2013 International Conference}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1876-6102}, doi = {10.1016/j.egypro.2014.03.157}, pages = {1481 -- 1490}, year = {2014}, abstract = {In this work the transient simulations of four hybrid solar tower power plant concepts with open-volumetric receiver technology for a location in Barstow-Daggett, USA, are presented. The open-volumetric receiver uses ambient air as heat transfer fluid and the hybridization is realized with a gas turbine. The Rankine cycle is heated by solar-heated air and/or by the gas turbine's flue gases. The plant can be operated in solar-only, hybrid parallel or combined cycle-only mode as well as in any intermediate load levels where the solar portion can vary between 0 to 100\%. The simulated plant is based on the configuration of a solar-hybrid power tower project, which is in planning for a site in Northern Algeria. The meteorological data for Barstow-Daggett was taken from the software meteonorm. The solar power tower simulation tool has been developed in the simulation environment MATLAB/Simulink and is validated.}, language = {en} } @article{PuppeGiulianoFrantzetal.2018, author = {Puppe, Michael and Giuliano, Stefano and Frantz, Cathy and Uhlig, Ralf and Schumacher, Ralph and Ibraheem, Wagdi and Schmalz, Stefan and Waldmann, Barbara and Guder, Christoph and Peter, Dennis and Schwager, Christian and Teixeira Boura, Cristiano Jos{\´e} and Alexopoulos, Spiros and Spiegel, Michael and Wortmann, J{\"u}rgen and Hinrichs, Matthias and Engelhard, Manfred and Aust, Michael}, title = {Techno-economic optimization of molten salt solar tower plants}, series = {AIP Conference Proceedings art.no. 040033}, volume = {2033}, journal = {AIP Conference Proceedings art.no. 040033}, number = {Issue 1}, publisher = {AIP Publishing}, address = {Melville, NY}, doi = {10.1063/1.5067069}, year = {2018}, abstract = {In this paper the results of a techno-economic analysis of improved and optimized molten salt solar tower plants (MSSTP plants) are presented. The potential improvements that were analyzed include different receiver designs, different designs of the HTF-system and plant control, increased molten salt temperatures (up to 640°C) and multi-tower systems. Detailed technological and economic models of the solar field, solar receiver and high temperature fluid system (HTF-system) were developed and used to find potential improvements compared to a reference plant based on Solar Two technology and up-to-date cost estimations. The annual yield model calculates the annual outputs and the LCOE of all variants. An improved external tubular receiver and improved HTF-system achieves a significant decrease of LCOE compared to the reference. This is caused by lower receiver cost as well as improvements of the HTF-system and plant operation strategy, significantly reducing the plant own consumption. A novel star receiver shows potential for further cost decrease. The cavity receiver concepts result in higher LCOE due to their high investment cost, despite achieving higher efficiencies. Increased molten salt temperatures seem possible with an adapted, closed loop HTF-system and achieve comparable results to the original improved system (with 565°C) under the given boundary conditions. In this analysis all multi tower systems show lower economic viability compared to single tower systems, caused by high additional cost for piping connections and higher cost of the receivers. REFERENCES}, language = {en} } @inproceedings{PompSchwarzboezlKolletal.2010, author = {Pomp, Stefan and Schwarzb{\"o}zl, Peter and Koll, Gerrit and Hennecke, Klaus and Schmitz, Mark and Hoffschmidt, Bernhard}, title = {Advanced concept for a solar thermal power plant with open volumetric air receiver}, 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 = {97 -- 98}, year = {2010}, language = {en} } @article{PeereBlanke2022, author = {Peere, Wouter and Blanke, Tobias}, title = {GHEtool: An open-source tool for borefield sizing in Python}, series = {Journal of Open Source Software}, volume = {7}, journal = {Journal of Open Source Software}, number = {76}, editor = {Vernon, Chris}, issn = {2475-9066}, doi = {10.21105/joss.04406}, pages = {1 -- 4, 4406}, year = {2022}, abstract = {GHEtool is a Python package that contains all the functionalities needed to deal with borefield design. It is developed for both researchers and practitioners. The core of this package is the automated sizing of borefield under different conditions. The sizing of a borefield is typically slow due to the high complexity of the mathematical background. Because this tool has a lot of precalculated data, GHEtool can size a borefield in the order of tenths of milliseconds. This sizing typically takes the order of minutes. Therefore, this tool is suited for being implemented in typical workflows where iterations are required. GHEtool also comes with a graphical user interface (GUI). This GUI is prebuilt as an exe-file because this provides access to all the functionalities without coding. A setup to install the GUI at the user-defined place is also implemented and available at: https://www.mech.kuleuven.be/en/tme/research/thermal_systems/tools/ghetool.}, language = {en} } @inproceedings{NiederwestbergSchneiderTeixeiraBouraetal.2022, author = {Niederwestberg, Stefan and Schneider, Falko and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf}, title = {Introduction to a direct irradiated transparent tube particle receiver}, 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 = {10.1063/5.0086735}, pages = {9 Seiten}, year = {2022}, abstract = {New materials often lead to innovations and advantages in technical applications. This also applies to the particle receiver proposed in this work that deploys high-temperature and scratch resistant transparent ceramics. With this receiver design, particles are heated through direct-contact concentrated solar irradiance while flowing downwards through tubular transparent ceramics from top to bottom. In this paper, the developed particle receiver as well as advantages and disadvantages are described. Investigations on the particle heat-up characteristics from solar irradiance were carried out with DEM simulations which indicate that particle temperatures can reach up to 1200 K. Additionally, a simulation model was set up for investigating the dynamic behavior. A test receiver at laboratory scale has been designed and is currently being built. In upcoming tests, the receiver test rig will be used to validate the simulation results. The design and the measurement equipment is described in this work.}, language = {en} } @inproceedings{NeumannAdamBackesetal.2021, author = {Neumann, Hannah and Adam, Mario and Backes, Klaus and B{\"o}rner, Martin and Clees, Tanja and Doetsch, Christian and Glaeser, Susanne and Herrmann, Ulf and May, Johanna and Rosenthal, Florian and Sauer, Dirk Uwe and Stadler, Ingo}, title = {Development of open educational resources for renewable energy and the energy transition process}, series = {ISES SWC 2021}, booktitle = {ISES SWC 2021}, publisher = {International Solar Energy Society}, address = {Freiburg}, doi = {10.18086/swc.2021.47.03}, pages = {6 Seiten}, year = {2021}, abstract = {The dissemination of knowledge about renewable energies is understood as a social task with the highest topicality. The transfer of teaching content on renewable energies into digital open educational resources offers the opportunity to significantly accelerate the implementation of the energy transition. Thus, in the here presented project six German universities create open educational resources for the energy transition. These materials are available to the public on the internet under a free license. So far there has been no publicly accessible, editable media that cover entire learning units about renewable energies extensively and in high technical quality. Thus, in this project, the content that remains up-to-date for a longer period is appropriately prepared in terms of media didactics. The materials enable lecturers to provide students with in-depth training about technologies for the energy transition. In a particular way, the created material is also suitable for making the general public knowledgeable about the energy transition with scientifically based material.}, language = {en} } @inproceedings{MohanGrossMenzeletal.2021, author = {Mohan, Nijanthan and Groß, Rolf Fritz and Menzel, Karsten and Theis, Fabian}, title = {Opportunities and Challenges in the Implementation of Building Information Modeling for Prefabrication of Heating, Ventilation and Air Conditioning Systems in Small and Medium-Sized Contracting Companies in Germany - A Case Study}, series = {WIT Transactions on The Built Environment, Vol. 205}, booktitle = {WIT Transactions on The Built Environment, Vol. 205}, publisher = {WIT Press}, address = {Southampton}, issn = {1743-3509}, doi = {10.2495/BIM210101}, pages = {117 -- 126}, year = {2021}, abstract = {FEven though BIM (Building Information Modelling) is successfully implemented in most of the world, it is still in the early stages in Germany, since the stakeholders are sceptical of its reliability and efficiency. The purpose of this paper is to analyse the opportunities and obstacles to implementing BIM for prefabrication. Among all other advantages of BIM, prefabrication is chosen for this paper because it plays a vital role in creating an impact on the time and cost factors of a construction project. The project stakeholders and participants can explicitly observe the positive impact of prefabrication, which enables the breakthrough of the scepticism factor among the small-scale construction companies. The analysis consists of the development of a process workflow for implementing prefabrication in building construction followed by a practical approach, which was executed with two case studies. It was planned in such a way that, the first case study gives a first-hand experience for the workers at the site on the BIM model so that they can make much use of the created BIM model, which is a better representation compared to the traditional 2D plan. The main aim of the first case study is to create a belief in the implementation of BIM Models, which was succeeded by the execution of offshore prefabrication in the second case study. Based on the case studies, the time analysis was made and it is inferred that the implementation of BIM for prefabrication can reduce construction time, ensures minimal wastes, better accuracy, less problem-solving at the construction site. It was observed that this process requires more planning time, better communication between different disciplines, which was the major obstacle for successful implementation. This paper was carried out from the perspective of small and medium-sized mechanical contracting companies for the private building sector in Germany.}, language = {en} } @inproceedings{MelissSpaeteLange1999, author = {Meliß, Michael and Sp{\"a}te, Frank and Lange, Harald}, title = {The Solar-Campus J{\"u}lich - an interdisciplinary project}, series = {Building a new century. 5th Conference on Solar Architecture and Design, Bonn, 27th of May 1998. Ed. by Eurosolar e.V. Ed. by Irm Pontenagel.}, booktitle = {Building a new century. 5th Conference on Solar Architecture and Design, Bonn, 27th of May 1998. Ed. by Eurosolar e.V. Ed. by Irm Pontenagel.}, publisher = {Eurosolar-Verl.}, address = {Bonn}, isbn = {3-933745-03-9}, pages = {382 -- 387}, year = {1999}, language = {en} } @article{MelissSpaete2000, author = {Meliß, Michael and Sp{\"a}te, Frank}, title = {The solar heating system with seasonal storage at the Solar-Campus J{\"u}lich}, series = {Solar energy. Vol. 69 (2000), iss. 6}, journal = {Solar energy. Vol. 69 (2000), iss. 6}, issn = {0038-092X}, pages = {525 -- 533}, year = {2000}, language = {en} } @inproceedings{MelissSpaete1996, author = {Meliß, Michael and Sp{\"a}te, Frank}, title = {Solar-Campus J{\"u}lich - an interdisciplinary project}, series = {EuroSun '96 ; 10. Internationales Sonnenforum : proceedings. Bd 3}, booktitle = {EuroSun '96 ; 10. Internationales Sonnenforum : proceedings. Bd 3}, publisher = {DGS-Sonnenenergie}, address = {M{\"u}nchen}, pages = {1281 -- 1285}, year = {1996}, language = {en} } @inproceedings{MelissSpaete1993, author = {Meliß, Michael and Sp{\"a}te, F.}, title = {The "Summerschool Renewable Energies" at the Fachhochschule Aachen, Abteilung 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 and 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 and education}, publisher = {Hungarian Energy Society}, address = {Budapest}, pages = {371 -- 376}, year = {1993}, language = {en} } @inproceedings{MelissNeskakisUsbecketal.1993, author = {Meliß, Michael and Neskakis, A. and Usbeck, S. and Wagner, L. and Wiediger, J{\"u}rgen}, title = {Energy supply by coupled solar systems for decentralized application}, 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. 8: Biomass, agriculture, wind}, 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. 8: Biomass, agriculture, wind}, publisher = {Hungarian Energy Society}, address = {Budapest}, pages = {343 -- 348}, year = {1993}, language = {en} } @inproceedings{MelissNeskakisUsbecketal.1992, author = {Meliß, Michael and Neskakis, A. and Usbeck, S. and Vogelsang, E. and Wagner, L. and Wiediger, J{\"u}rgen}, title = {PV-transmitter and receiver}, 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. 3: Photovoltaics}, 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. 3: Photovoltaics}, publisher = {Hungarian Energy Society}, address = {Budapest}, pages = {375 -- 380}, year = {1992}, language = {en} } @article{MelissNeskakisPlettnerMarlianietal.1998, author = {Meliß, Michael and Neskakis, A. and Plettner-Marliani, J. and Lange, C. and H{\"o}velmann, A. and Schumacher, J.}, title = {Waste water recycling supplied by renewable energies : basic conditions and possible treatment technologies}, series = {Renewable energy. Vol. 14 (1998), iss. 1-4. 6th Arab International Solar Energy Conference: Bringing Solar Energy into the Daylight, Muscat, Sultanate of Oman, 29.03.-01.04.1998}, journal = {Renewable energy. Vol. 14 (1998), iss. 1-4. 6th Arab International Solar Energy Conference: Bringing Solar Energy into the Daylight, Muscat, Sultanate of Oman, 29.03.-01.04.1998}, issn = {1879-0682 (E-Book); 0960-1481 (Print)}, pages = {325 -- 331}, year = {1998}, language = {en} } @inproceedings{MayBreitbachAlexopoulosetal.2019, author = {May, Martin and Breitbach, Gerd and Alexopoulos, Spiros and Latzke, Markus and B{\"a}umer, Klaus and Uhlig, Ralf and S{\"o}hn, Matthias and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf}, title = {Experimental facility for investigations of wire mesh absorbers for pressurized gases}, series = {AIP Conference Proceedings}, volume = {2126}, booktitle = {AIP Conference Proceedings}, issn = {0094243X}, doi = {10.1063/1.5117547}, pages = {030035-1 -- 030035-9}, year = {2019}, language = {en} } @inproceedings{MarcusMelissSpaete1993, author = {Marcus, W. and Meliß, Michael and Sp{\"a}te, F.}, title = {Street lighting and advertising with photovoltaics}, 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. 3: Photovoltaics}, 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. 3: Photovoltaics}, publisher = {Hungarian Energy Society}, address = {Budapest}, pages = {509 -- 514}, year = {1993}, language = {en} } @inproceedings{MahdiRendonSchwageretal.2019, author = {Mahdi, Zahra and Rend{\´o}n, Carlos and Schwager, Christian and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf}, title = {Novel concept for indirect solar-heated methane reforming}, series = {AIP Conference Proceedings}, volume = {2126}, booktitle = {AIP Conference Proceedings}, publisher = {AIP Publishing}, address = {Melville, NY}, issn = {0094-243X}, doi = {10.1063/1.5117694}, pages = {180014-1 -- 180014-7}, year = {2019}, language = {en} } @inproceedings{MahdiDerschSchmitzetal.2022, author = {Mahdi, Zahra and Dersch, J{\"u}rgen and Schmitz, Pascal and Dieckmann, Simon and Caminos, Ricardo Alexander Chico and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf and Schwager, Christian and Schmitz, Mark and Gielen, Hans and Gedle, Yibekal and B{\"u}scher, Rauno}, title = {Technical assessment of Brayton cycle heat pumps for the integration in hybrid PV-CSP 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 = {10.1063/5.0086269}, pages = {11 Seiten}, year = {2022}, abstract = {The hybridization of Concentrated Solar Power (CSP) and Photovoltaics (PV) systems is a promising approach to reduce costs of solar power plants, while increasing dispatchability and flexibility of power generation. High temperature heat pumps (HT HP) can be utilized to boost the salt temperature in the thermal energy storage (TES) of a Parabolic Trough Collector (PTC) system from 385 °C up to 565 °C. A PV field can supply the power for the HT HP, thus effectively storing the PV power as thermal energy. Besides cost-efficiently storing energy from the PV field, the power block efficiency of the overall system is improved due to the higher steam parameters. This paper presents a technical assessment of Brayton cycle heat pumps to be integrated in hybrid PV-CSP power plants. As a first step, a theoretical analysis was carried out to find the most suitable working fluid. The analysis included the fluids Air, Argon (Ar), Nitrogen (N2) and Carbon dioxide (CO2). N2 has been chosen as the optimal working fluid for the system. After the selection of the ideal working medium, different concepts for the arrangement of a HT HP in a PV-CSP hybrid power plant were developed and simulated in EBSILON®Professional. The concepts were evaluated technically by comparing the number of components required, pressure losses and coefficient of performance (COP).}, language = {en} } @inproceedings{LuepfertHerrmannPriceetal.2004, author = {L{\"u}pfert, E. and Herrmann, Ulf and Price, Henry and Zarza, E. and Kistener, R.}, title = {Towards Standard Performance Analysis for Parabolic Trough Collector Fields}, series = {12th International Symposium Solar Power and Chemical Energy Systems, October 6-8, 2004, Oaxaca Mexico ; SolarPACES International Symposium, 12}, booktitle = {12th International Symposium Solar Power and Chemical Energy Systems, October 6-8, 2004, Oaxaca Mexico ; SolarPACES International Symposium, 12}, editor = {Ramos, C.}, publisher = {Instituto de Investigaciones Electricas}, address = {[s.l.]}, isbn = {968-6114-18-1}, year = {2004}, language = {en} } @inproceedings{LatzkeAlexopoulosKronhardtetal.2015, author = {Latzke, Markus and Alexopoulos, Spiros and Kronhardt, Valentina and Rend{\´o}n, Carlos and Sattler, Johannes, Christoph}, title = {Comparison of Potential Sites in China for Erecting a Hybrid Solar Tower Power Plant with Air Receiver}, series = {Energy Procedia}, booktitle = {Energy Procedia}, issn = {1876-6102}, doi = {10.1016/j.egypro.2015.03.142}, pages = {1327 -- 1334}, year = {2015}, language = {en} } @inproceedings{LahrsKrisamHerrmann2023, author = {Lahrs, Lennart and Krisam, Pierre and Herrmann, Ulf}, title = {Envisioning a collaborative energy system planning platform for the energy transition at the district level}, series = {The 36th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems}, booktitle = {The 36th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems}, publisher = {Procedings of ECOS 2023}, doi = {10.52202/069564-0284}, pages = {3163 -- 3170}, year = {2023}, abstract = {Residential and commercial buildings account for more than one-third of global energy-related greenhouse gas emissions. Integrated multi-energy systems at the district level are a promising way to reduce greenhouse gas emissions by exploiting economies of scale and synergies between energy sources. Planning district energy systems comes with many challenges in an ever-changing environment. Computational modelling established itself as the state-of-the-art method for district energy system planning. Unfortunately, it is still cumbersome to combine standalone models to generate insights that surpass their original purpose. Ideally, planning processes could be solved by using modular tools that easily incorporate the variety of competing and complementing computational models. Our contribution is a vision for a collaborative development and application platform for multi-energy system planning tools at the district level. We present challenges of district energy system planning identified in the literature and evaluate whether this platform can help to overcome these challenges. Further, we propose a toolkit that represents the core technical elements of the platform. Lastly, we discuss community management and its relevance for the success of projects with collaboration and knowledge sharing at their core.}, language = {en} } @inproceedings{KruegerAnthrakidisFischeretal.2009, author = {Kr{\"u}ger, Dirk and Anthrakidis, Anette and Fischer, Stephan and Lokurlu, Ahmet and Walder, Markus and Croy, Reiner and Quaschning, Volker}, title = {Experiences with solar steam supply for an industrial steam network in the P3 Project}, series = {SolarPACES 2009 : electricity, fuels and clean water powered by the sun ; 15 - 18 September 2009, Berlin, Germany ; the 15th SolarPACES conference ; proceedings}, booktitle = {SolarPACES 2009 : electricity, fuels and clean water powered by the sun ; 15 - 18 September 2009, Berlin, Germany ; the 15th SolarPACES conference ; proceedings}, publisher = {Deutsches Zentrum f. Luft- u. Raumfahrt}, address = {Stuttgart}, isbn = {9783000287558}, pages = {1 CD-ROM}, year = {2009}, language = {en} } @article{KronhardtAlexopoulosReisseletal.2014, author = {Kronhardt, Valentina and Alexopoulos, Spiros and Reißel, Martin and Sattler, Johannes, Christoph and Hoffschmidt, Bernhard and H{\"a}nel, Matthias and Doerbeck, Till}, title = {High-temperature thermal storage system for solar tower power plants with open-volumetric air receiver simulation and energy balancing of a discretized model}, series = {Energy procedia}, volume = {49}, journal = {Energy procedia}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1876-6102 (E-Journal) ; 1876-6102 (Print)}, doi = {10.1016/j.egypro.2014.03.094}, pages = {870 -- 877}, year = {2014}, abstract = {This paper describes the modeling of a high-temperature storage system for an existing solar tower power plant with open volumetric receiver technology, which uses air as heat transfer medium (HTF). The storage system model has been developed in the simulation environment Matlab/Simulink®. The storage type under investigation is a packed bed thermal energy storage system which has the characteristics of a regenerator. Thermal energy can be stored and discharged as required via the HTF air. The air mass flow distribution is controlled by valves, and the mass flow by two blowers. The thermal storage operation strategy has a direct and significant impact on the energetic and economic efficiency of the solar tower power plants.}, language = {en} } @incollection{KrokerHoffschmidtSchwarzeretal.2008, author = {Kroker, Jan and Hoffschmidt, Bernhard and Schwarzer, Klemens and Sp{\"a}te, Frank}, title = {PTC 1000 modular parabolic trough collector}, series = {Process heat collectors : state of the art within task 33/IV ; IEA SHC-Task 33 and SolarPACES-Task IV: Solar heat for industrial processes : F{\"o}rderkennzeichen BMBF 0329273A / Solar Heating and Cooling Executive Committee of the International Energy Agency (IEA) ; ed. Werner Weiss}, booktitle = {Process heat collectors : state of the art within task 33/IV ; IEA SHC-Task 33 and SolarPACES-Task IV: Solar heat for industrial processes : F{\"o}rderkennzeichen BMBF 0329273A / Solar Heating and Cooling Executive Committee of the International Energy Agency (IEA) ; ed. Werner Weiss}, publisher = {AEE INTEC}, address = {Gleisdorf}, pages = {45 -- 46}, year = {2008}, language = {en} } @inproceedings{KreyerMuellerEsch2020, author = {Kreyer, J{\"o}rg and M{\"u}ller, Marvin and Esch, Thomas}, title = {A Map-Based Model for the Determination of Fuel Consumption for Internal Combustion Engines as a Function of Flight Altitude}, series = {Deutscher Luft- und Raumfahrtkongress 2019, „Luft- und Raumfahrt - technologische Br{\"u}cke in die Zukunft", Darmstadt, 30. September bis 2. Oktober 2019}, booktitle = {Deutscher Luft- und Raumfahrtkongress 2019, „Luft- und Raumfahrt - technologische Br{\"u}cke in die Zukunft", Darmstadt, 30. September bis 2. Oktober 2019}, publisher = {Deutsche Gesellschaft f{\"u}r Luft- und Raumfahrt - Lilienthal-Oberth e.V}, address = {Bonn}, doi = {10.25967/490162}, pages = {13 Seiten}, year = {2020}, language = {en} } @inproceedings{KollSchwarzboezlHenneckeetal.2009, author = {Koll, Gerrit and Schwarzb{\"o}zl, Peter and Hennecke, Klaus and Hartz, Thomas and Schmitz, Mark and Hoffschmidt, Bernhard}, title = {The Solar Tower J{\"u}lich - a research and demonstration plant for central receiver systems}, series = {SolarPACES 2009 : electricity, fuels and clean water powered by the sun ; 15 - 18 September 2009, Berlin, Germany ; the 15th SolarPACES conference ; proceedings}, booktitle = {SolarPACES 2009 : electricity, fuels and clean water powered by the sun ; 15 - 18 September 2009, Berlin, Germany ; the 15th SolarPACES conference ; proceedings}, publisher = {Deutsches Zentrum f. Luft- u. Raumfahrt}, address = {Stuttgart}, isbn = {9783000287558}, pages = {1 CD-ROM}, year = {2009}, language = {en} } @article{KluczkaEcksteinAlexopoulosetal.2014, author = {Kluczka, Sven and Eckstein, Julian and Alexopoulos, Spiros and Vaeßen, Christiane and Roeb, Martin}, title = {Process simulation for solar steam and dry reforming}, series = {Energy procedia : Proceedings of the SolarPACES 2013 International Conference}, volume = {49}, journal = {Energy procedia : Proceedings of the SolarPACES 2013 International Conference}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1876-6102 (E-Journal)}, doi = {10.1016/j.egypro.2014.03.092}, pages = {850 -- 859}, year = {2014}, abstract = {In co-operation with the German Aerospace Center, the Solar-Institut J{\"u}lich has been analyzing the different technologies that are available for methanol production from CO2 using solar energy. The aim of the project is to extract CO2 from industrial exhaust gases or directly from the atmosphere to recycle it by use of solar energy. Part of the study was the modeling and simulating of a methane reformer for the production of synthesis gas, which can be operated by solar or hybrid heat sources. The reformer has been simplified in such a way that the model is accurate and enables fast calculations. The developed pseudo-homogeneous one- dimensional model can be regarded as a kind of counter-current heat exchanger and is able to incorporate a steam reforming reaction as well as a dry reforming reaction.}, language = {en} } @inproceedings{KellyHerrmannHale2001, author = {Kelly, Bruce and Herrmann, Ulf and Hale, M.-J.}, title = {Optimization Studies for Integrated Solar Combined Cycle Systems}, series = {Solar engineering 2001 : proceedings of the International Solar Energy Conference ; presented at the 2001 International Solar Energy Conference, a part of Forum 2001 - Solar energy: the power to choose, April 21 - 25, 2001, Washington, D.C.}, booktitle = {Solar engineering 2001 : proceedings of the International Solar Energy Conference ; presented at the 2001 International Solar Energy Conference, a part of Forum 2001 - Solar energy: the power to choose, April 21 - 25, 2001, Washington, D.C.}, publisher = {ASME}, address = {New York, NY}, isbn = {0-7918-1670-2}, pages = {393 -- 398}, year = {2001}, language = {en} } @article{KearneyKellyHerrmannetal.2002, author = {Kearney, David W. and Kelly, Bruce and Herrmann, Ulf and Cable, R. and Pacheco, J. and Mahoney, R. and Price, Henry and Blake, D. and Nava, P. and Potrovitza, N.}, title = {Engineering Aspects of a Molten Salt Heat Transfer Fluid in a Trough Solar Field}, series = {Energy : the international journal}, volume = {29}, journal = {Energy : the international journal}, number = {5-6 (Special Issue SolarPaces)}, issn = {0360-5442}, doi = {10.1016/S0360-5442(03)00191-9}, pages = {861 -- 870}, year = {2002}, language = {en} } @article{KearneyHerrmannNavaetal.2003, author = {Kearney, D. and Herrmann, Ulf and Nava, P. and Kelly, B. and Mahoney, R. and Pacheco, J. and Cable, R. and Potrovitza, N. and Blake, D. and Price, H.}, title = {Assessment of a Molten Salt Heat Transfer Fluid in a Parabolic Trough Solar Field}, series = {Journal of Solar Energy Engineering}, volume = {125}, journal = {Journal of Solar Energy Engineering}, number = {2}, issn = {1528-8986}, doi = {10.1115/1.1565087}, pages = {170 -- 176}, year = {2003}, language = {en} } @inproceedings{JanotteFecklerKoetteretal.2014, author = {Janotte, N. and Feckler, G. and K{\"o}tter, Jens and Decker, Stefan and Herrmann, Ulf and Schmitz, Mark and L{\"u}pfert, E.}, title = {Dynamic performance evaluation of the HelioTrough® collector demonstration loop : towards a new benchmark in parabolic trough qualification}, series = {SolarPACES International Conference 2013, Las Vegas, Nevada, USA, 17 - 20 September 2013 : [proceedings]. - Pt. 1. - (Energy procedia ; 49)}, booktitle = {SolarPACES International Conference 2013, Las Vegas, Nevada, USA, 17 - 20 September 2013 : [proceedings]. - Pt. 1. - (Energy procedia ; 49)}, publisher = {Curran}, address = {Red Hook, NY}, isbn = {978-1-63266-904-9}, issn = {1876-6102}, doi = {10.1016/j.egypro.2014.03.012}, pages = {109 -- 117}, year = {2014}, language = {en} } @inproceedings{HoffschmidtTelleSauerbornetal.2011, author = {Hoffschmidt, Bernhard and Telle, R. and Sauerborn, Markus and Wagner, M.}, title = {Optical measurement system for high temperature absorbers}, 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{HoffschmidtSchwarzerSpaeteetal.2006, author = {Hoffschmidt, Bernhard and Schwarzer, Klemens and Sp{\"a}te, Frank and K{\"o}tter, Jens and Ebert, Miriam and Sierck, Olaf}, title = {Development of a small modular parabolic trough collector}, series = {13th International Symposium Concentrated Solar Power and Chemical Energy Technologies : SolarPaces : June 20 - 23, 2006, Seville, Spain}, booktitle = {13th International Symposium Concentrated Solar Power and Chemical Energy Technologies : SolarPaces : June 20 - 23, 2006, Seville, Spain}, publisher = {SolarPaces}, address = {[o.O.]}, organization = {International Symposium on Concentrating Solar Power and Chemical Energy Systems <13, 2006, Sevilla>}, isbn = {8478345191}, pages = {1 CD-ROM}, year = {2006}, language = {en} } @incollection{HoffschmidtFaber2007, author = {Hoffschmidt, Bernhard and Faber, Christian}, title = {Lighthouse project for North-Rhine Westfalia - Solar thermal R \& D Power Planet in J{\"u}lich}, series = {Energy security, climate change and sustainable development / ed. Jyotirmay Mathur ...}, booktitle = {Energy security, climate change and sustainable development / ed. Jyotirmay Mathur ...}, publisher = {Anamaya Publ.}, address = {New Delhi}, isbn = {81-88342-81-5}, pages = {101 -- 116}, year = {2007}, language = {en} } @incollection{HoffschmidtAlexopoulosRauetal.2022, author = {Hoffschmidt, Bernhard and Alexopoulos, Spiros and Rau, Christoph and Sattler, Johannes, Christoph and Anthrakidis, Anette and Teixeira Boura, Cristiano Jos{\´e} and O'Connor, B. and Chico Caminos, R.A. and Rend{\´o}n, C. and Hilger, P.}, title = {Concentrating solar power}, series = {Comprehensive Renewable Energy (Second Edition) / Volume 3: Solar Thermal Systems: Components and Applications}, booktitle = {Comprehensive Renewable Energy (Second Edition) / Volume 3: Solar Thermal Systems: Components and Applications}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {978-0-12-819734-9}, pages = {670 -- 724}, year = {2022}, abstract = {The focus of this chapter is the production of power and the use of the heat produced from concentrated solar thermal power (CSP) systems. The chapter starts with the general theoretical principles of concentrating systems including the description of the concentration ratio, the energy and mass balance. The power conversion systems is the main part where solar-only operation and the increase in operational hours. Solar-only operation include the use of steam turbines, gas turbines, organic Rankine cycles and solar dishes. The operational hours can be increased with hybridization and with storage. Another important topic is the cogeneration where solar cooling, desalination and of heat usage is described. Many examples of commercial CSP power plants as well as research facilities from the past as well as current installed and in operation are described in detail. The chapter closes with economic and environmental aspects and with the future potential of the development of CSP around the world.}, language = {en} } @incollection{HoffschmidtAlexopoulosRauetal.2021, author = {Hoffschmidt, Bernhard and Alexopoulos, Spiros and Rau, Christoph and Sattler, Johannes, Christoph and Anthrakidis, Anette and Teixeira Boura, Cristiano Jos{\´e} and O'Connor, B. and Caminos, R.A. Chico and Rend{\´o}n, C. and Hilger, P.}, title = {Concentrating Solar Power}, series = {Earth systems and environmental sciences}, booktitle = {Earth systems and environmental sciences}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {978-0-12-409548-9}, doi = {10.1016/B978-0-12-819727-1.00089-3}, year = {2021}, abstract = {The focus of this chapter is the production of power and the use of the heat produced from concentrated solar thermal power (CSP) systems. The chapter starts with the general theoretical principles of concentrating systems including the description of the concentration ratio, the energy and mass balance. The power conversion systems is the main part where solar-only operation and the increase in operational hours. Solar-only operation include the use of steam turbines, gas turbines, organic Rankine cycles and solar dishes. The operational hours can be increased with hybridization and with storage. Another important topic is the cogeneration where solar cooling, desalination and of heat usage is described. Many examples of commercial CSP power plants as well as research facilities from the past as well as current installed and in operation are described in detail. The chapter closes with economic and environmental aspects and with the future potential of the development of CSP around the world.}, language = {en} } @incollection{HoffschmidtAlexopoulosRauetal.2012, author = {Hoffschmidt, Bernhard and Alexopoulos, Spiros and Rau, Christoph and Sattler, Johannes, Christoph and Anthrakidis, Anette and Teixeira Boura, Cristiano Jos{\´e} and O'Connor, P. and Hilger, Patrick}, title = {Concentrating solar power}, series = {Comprehensive renewable energy / ed. Ali Sayigh. Vol. 3: Solar thermal systems: components and applications}, volume = {3}, booktitle = {Comprehensive renewable energy / ed. Ali Sayigh. Vol. 3: Solar thermal systems: components and applications}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {978-0-08-087872-0}, doi = {10.1016/B978-0-08-087872-0.00319-X}, pages = {595 -- 636}, year = {2012}, language = {en} } @incollection{HoffschmidtAlexopoulosGoettscheetal.2022, author = {Hoffschmidt, Bernhard and Alexopoulos, Spiros and G{\"o}ttsche, Joachim and Sauerborn, Markus and Kaufhold, O.}, title = {High Concentration Solar Collectors}, series = {Comprehensive Renewable Energy (Second Edition) / Volume 3: Solar Thermal Systems: Components and Applications}, booktitle = {Comprehensive Renewable Energy (Second Edition) / Volume 3: Solar Thermal Systems: Components and Applications}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {978-0-12-819734-9}, doi = {10.1016/B978-0-12-819727-1.00058-3}, pages = {198 -- 245}, year = {2022}, abstract = {Solar thermal concentrated power is an emerging technology that provides clean electricity for the growing energy market. To the solar thermal concentrated power plant systems belong the parabolic trough, the Fresnel collector, the solar dish, and the central receiver system. For high-concentration solar collector systems, optical and thermal analysis is essential. There exist a number of measurement techniques and systems for the optical and thermal characterization of the efficiency of solar thermal concentrated systems. For each system, structure, components, and specific characteristics types are described. The chapter presents additionally an outline for the calculation of system performance and operation and maintenance topics. One main focus is set to the models of components and their construction details as well as different types on the market. In the later part of this article, different criteria for the choice of technology are analyzed in detail.}, language = {en} } @incollection{HoffschmidtAlexopoulosGoettscheetal.2012, author = {Hoffschmidt, Bernhard and Alexopoulos, Spiros and G{\"o}ttsche, Joachim and Sauerborn, Markus}, title = {High concentration solar collectors}, series = {Comprehensive renewable energy / ed. Ali Sayigh. Vol. 3: Solar thermal systems: components and applications}, volume = {3}, booktitle = {Comprehensive renewable energy / ed. Ali Sayigh. Vol. 3: Solar thermal systems: components and applications}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {978-0-08-087873-7}, doi = {10.1016/B978-0-08-087872-0.00306-1}, pages = {165 -- 209}, year = {2012}, abstract = {Solar thermal concentrated power is an emerging technology that provides clean electricity for the growing energy market. To the solar thermal concentrated power plant systems belong the parabolic trough, the Fresnel collector, the solar dish, and the central receiver system. For high-concentration solar collector systems, optical and thermal analysis is essential. There exist a number of measurement techniques and systems for the optical and thermal characterization of the efficiency of solar thermal concentrated systems. For each system, structure, components, and specific characteristics types are described. The chapter presents additionally an outline for the calculation of system performance and operation and maintenance topics. One main focus is set to the models of components and their construction details as well as different types on the market. In the later part of this chapter, different criteria for the choice of technology are analyzed in detail.}, language = {en} } @inproceedings{Hoffschmidt2008, author = {Hoffschmidt, Bernhard}, title = {Solar tower power plants}, 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 = {Duisbrug}, 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{HirschAhlbrinkPitzPaaletal.2011, author = {Hirsch, Tobias and Ahlbrink, Nils and Pitz-Paal, Robert and Teixeira Boura, Cristiano Jos{\´e} and Hoffschmidt, Bernhard and Gall, Jan and Abel, Dirk and Nolte, Vera and Wirsum, Manfred and Andersson, Joel and Diehl, Moritz}, title = {Dynamic simulation of a solar tower system with open volumetric receiver - a review on the ViCERP project}, 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{HirschAbelBohnetal.2009, author = {Hirsch, Tobias and Abel, Dirk and Bohn, Dieter and Diehl, Moritz and Hoffschmidt, Bernhard and Pitz-Paal, Robert}, title = {The Virtual Institute for Central Receiver Power Plants - vICERP}, series = {SolarPACES 2009 : electricity, fuels and clean water powered by the sun ; 15 - 18 September 2009, Berlin, Germany ; the 15th SolarPACES conference ; proceedings}, booktitle = {SolarPACES 2009 : electricity, fuels and clean water powered by the sun ; 15 - 18 September 2009, Berlin, Germany ; the 15th SolarPACES conference ; proceedings}, publisher = {Deutsches Zentrum f. Luft- u. Raumfahrt}, address = {Stuttgart}, isbn = {9783000287558}, pages = {1 CD-ROM}, year = {2009}, language = {en} } @inproceedings{HerrmannWorringerGraeteretal.2006, author = {Herrmann, Ulf and Worringer, S. and Graeter, F. and Nava, P.}, title = {Three Years of Operation Experience of the SKAL-ET Collector Loop at SEGS V}, series = {13th International Symposium Concentrated Solar Power and Chemical Energy Technologies, June 20 - 23, 2006, Seville, Spain}, booktitle = {13th International Symposium Concentrated Solar Power and Chemical Energy Technologies, June 20 - 23, 2006, Seville, Spain}, editor = {Romero, Manuel}, publisher = {SolarPACES [u.a.]}, address = {[s.l.]}, isbn = {84-7834-519-1}, pages = {1 CD-ROM}, year = {2006}, language = {en} } @inproceedings{HerrmannVorbruggNava2009, author = {Herrmann, Ulf and Vorbrugg, O. and Nava, P.}, title = {Construction and Commissioning Process of the Andasol Solar Field}, series = {SolarPACES 2009 : electricity, fuels and clean water powered by the sun ; 15 - 18 September 2009, Berlin, Germany ; the 15th SolarPACES conference ; proceedings}, booktitle = {SolarPACES 2009 : electricity, fuels and clean water powered by the sun ; 15 - 18 September 2009, Berlin, Germany ; the 15th SolarPACES conference ; proceedings}, publisher = {Deutsches Zentrum f{\"u}r Luft- u. Raumfahrt}, address = {Stuttgart}, isbn = {978-3-00-028755-8}, pages = {1 CD-ROM}, year = {2009}, language = {en} } @inproceedings{HerrmannRheinlaenderLippke1997, author = {Herrmann, Ulf and Rheinl{\"a}nder, J. and Lippke, F.}, title = {Solar Fields for Direct Steam Generation in Parabolic Trough Collectors}, series = {Components, tools, facilities and measurement techniques. - (Solar thermal concentrating technologies : proceedings of the 8th international symposium, October, 6 - 11, 1996, K{\"o}ln, Germany ; Vol. 2)}, booktitle = {Components, tools, facilities and measurement techniques. - (Solar thermal concentrating technologies : proceedings of the 8th international symposium, October, 6 - 11, 1996, K{\"o}ln, Germany ; Vol. 2)}, editor = {Becker, Manfred}, publisher = {M{\"u}ller}, address = {Heidelberg}, isbn = {3-7880-7616-X}, pages = {815 -- 834}, year = {1997}, language = {en} } @article{HerrmannLippke1999, author = {Herrmann, Ulf and Lippke, F.}, title = {The influence of transients on the design of DSG solar fields}, series = {Journal de Physique IV : proceedings}, volume = {9}, journal = {Journal de Physique IV : proceedings}, number = {PR3}, isbn = {2-86883-402-7}, issn = {1764-7177 (Online)}, doi = {10.1051/jp4:1999377}, pages = {489 -- 494}, year = {1999}, language = {en} } @article{HerrmannKellyPrice2002, author = {Herrmann, Ulf and Kelly, Bruce and Price, Henry}, title = {Two Tank Molten Salt Storage for Parabolic Trough Solar Power Plants}, series = {Energy : the international journal}, volume = {29}, journal = {Energy : the international journal}, number = {5-6 (Special Issue SolarPaces)}, issn = {0360-5442}, doi = {10.1016/S0360-5442(03)00193-2}, pages = {883 -- 893}, year = {2002}, language = {en} } @inproceedings{HerrmannKellyPrice2002, author = {Herrmann, Ulf and Kelly, Bruce and Price, Henry}, title = {Two Tank Molten Salt Storage for Parabolic Trough Solar Power Plants}, series = {Proceedings of the 11th SolarPACES International Symposium on Concentrated Solar Power and Chemical Energy Technologies : September 4 - 6, 2002, Zurich, Switzerland / Paul Scherrer Institut, PSI; ETH, Eidgen{\"o}ssische Technische Hochschule Z{\"u}rich}, booktitle = {Proceedings of the 11th SolarPACES International Symposium on Concentrated Solar Power and Chemical Energy Technologies : September 4 - 6, 2002, Zurich, Switzerland / Paul Scherrer Institut, PSI; ETH, Eidgen{\"o}ssische Technische Hochschule Z{\"u}rich}, editor = {Steinfeld, Aldo}, publisher = {Paul Scherrer Inst.}, address = {Villingen}, isbn = {3-9521409-3-7}, pages = {517 -- 524}, year = {2002}, language = {en} } @article{HerrmannKearney2002, author = {Herrmann, Ulf and Kearney, David W.}, title = {Survey of Thermal Energy Storage for Parabolic Trough Power Plants}, series = {Journal of Solar Energy Engineering}, volume = {124}, journal = {Journal of Solar Energy Engineering}, number = {2}, issn = {1528-8986 (Online)}, doi = {10.1115/1.1467601}, pages = {145 -- 152}, year = {2002}, language = {en} } @incollection{HerrmannKearneyRoegeretal.2017, author = {Herrmann, Ulf and Kearney, D. and R{\"o}ger, M. and Prahl, C.}, title = {System performance measurements}, series = {The Performance of Concentrated Solar Power (CSP) Systems : Modelling, Measurement and Assessment}, booktitle = {The Performance of Concentrated Solar Power (CSP) Systems : Modelling, Measurement and Assessment}, publisher = {Woodhead Publishing}, address = {Duxford}, isbn = {978-0-08-100448-7}, doi = {https://doi.org/10.1016/B978-0-08-100447-0.00005-5}, pages = {115 -- 165}, year = {2017}, abstract = {This chapter introduces performance and acceptance testing and describes state-of-the-art tools, methods, and instruments to assess the plant performance or realize plant acceptance testing. The status of the development of standards for performance assessment is given.}, language = {en} } @inproceedings{HerrmannGraeterNava2004, author = {Herrmann, Ulf and Graeter, F. and Nava, P.}, title = {Performance of the SKAL-ET Collector Loop at KJC Operating Company}, series = {12th International Symposium Solar Power and Chemical Energy Systems, October 6-8, 2004, Oaxaca Mexico ; SolarPACES International Symposium, 12}, booktitle = {12th International Symposium Solar Power and Chemical Energy Systems, October 6-8, 2004, Oaxaca Mexico ; SolarPACES International Symposium, 12}, editor = {Ramos, C.}, publisher = {Instituto de Investigaciones Electricas}, address = {[s.l.]}, isbn = {968-6114-18-1}, year = {2004}, language = {en} } @article{HenneckeSchwarzboezlHoffschmidtetal.2007, author = {Hennecke, Klaus and Schwarzb{\"o}zl, Peter and Hoffschmidt, Bernhard and G{\"o}ttsche, Joachim and Koll, G. and Beuter, M. and Hartz, T.}, title = {The solar power tower J{\"u}lich - a solar thermal power plant for test and demonstration of air receiver}, series = {Solar energy and human settlement : Elektronische Ressource : proceedings of ISES world congress 2007 ; (Vol. I - Vol. V) / [ISES Solar World Congress. ISES, International Solar Energy Society]. D. Yogi Goswami ; Yuwen Zhao}, journal = {Solar energy and human settlement : Elektronische Ressource : proceedings of ISES world congress 2007 ; (Vol. I - Vol. V) / [ISES Solar World Congress. ISES, International Solar Energy Society]. D. Yogi Goswami ; Yuwen Zhao}, publisher = {Tsinghua Univ. Press}, address = {Beijing}, isbn = {978-7-302-16146-2}, pages = {1749 -- 1753}, year = {2007}, language = {en} } @inproceedings{HahneHerrmannRheinlaender1997, author = {Hahne, E. and Herrmann, Ulf and Rheinl{\"a}nder, J.}, title = {The Effect of Tilt on Flow Pattern of Water/Steam Flow Through Heated Tubes}, series = {Experimental heat transfer, fluid mechanics and thermodynamics 1997 : proceedings of the 4th World Conference on Experimental Heat Transfer, Fluid Mechanics and Thermodynamics, Brussels, June 2 - 6, 1997. - Vol. 2}, booktitle = {Experimental heat transfer, fluid mechanics and thermodynamics 1997 : proceedings of the 4th World Conference on Experimental Heat Transfer, Fluid Mechanics and Thermodynamics, Brussels, June 2 - 6, 1997. - Vol. 2}, editor = {Girot, Michel}, publisher = {Ed. ETS}, address = {Pisa}, isbn = {88-467-0014-7}, pages = {925 -- 934}, year = {1997}, language = {en} } @inproceedings{GoettscheSchwarzerRoetheretal.2009, author = {G{\"o}ttsche, Joachim and Schwarzer, Klemens and R{\"o}ther, Sascha and Jellinghaus, Sabine and Helten, G. and Wittmann, R.}, title = {Efficient daylighting, heating and shading with rooflight heliostats}, series = {Renewables in a changing climate : from Nano to Urban Scale : CISBAT 2009 : 2-3 September 2009, EPFL, Lausanne, Switzerland : proceedings}, booktitle = {Renewables in a changing climate : from Nano to Urban Scale : CISBAT 2009 : 2-3 September 2009, EPFL, Lausanne, Switzerland : proceedings}, publisher = {Ecole Polytechnique F{\´e}d{\´e}rale de Lausanne}, address = {Lausanne}, pages = {243 -- 246}, year = {2009}, language = {en} } @article{GoettscheSchwarzerRoetheretal.2009, author = {G{\"o}ttsche, Joachim and Schwarzer, Klemens and R{\"o}ther, S. and Jellinghaus, Sabine}, title = {Efficient daylighting, heating and shading with rooflight heliostats}, series = {Conference Internationale Energie Solaire et Batiment}, journal = {Conference Internationale Energie Solaire et Batiment}, publisher = {EPFL}, address = {Lausanne}, pages = {243 -- 248}, year = {2009}, language = {en} } @article{GoettscheReillyWittwer1991, author = {G{\"o}ttsche, Joachim and Reilly, S. and Wittwer, Volker}, title = {Advanced window systems and building energy performance / S. Reilly ; J. G{\"o}ttsche ; V. Wittwer}, series = {Solar World Congress, 1991 : proceedings of the biennial congress of the International Solar Energy Society, Denver, Colorado, USA, 19-23 August 1991 / ed. by M. E. Arden ...}, journal = {Solar World Congress, 1991 : proceedings of the biennial congress of the International Solar Energy Society, Denver, Colorado, USA, 19-23 August 1991 / ed. by M. E. Arden ...}, publisher = {Pergamon Press}, address = {Oxford [u.a.]}, isbn = {0-08-041690-X}, pages = {3211 -- 3216}, year = {1991}, language = {en} } @article{GoettscheHove1999, author = {G{\"o}ttsche, Joachim and Hove, T.}, title = {Mapping global, diffuse and beam solar radiation over Zimbabwe / T. Hove ; J. G{\"o}ttsche}, series = {Renewable energy. 18 (1999), H. 4}, journal = {Renewable energy. 18 (1999), H. 4}, isbn = {1879-0682}, pages = {535 -- 556}, year = {1999}, language = {en} } @article{GoettscheHoffschmidtSchmitzetal.2009, author = {G{\"o}ttsche, Joachim and Hoffschmidt, Bernhard and Schmitz, Stefan and Sauerborn, Markus}, title = {Solar Concentrating Systems Using Small Mirror Arrays / G{\"o}ttsche, Joachim ; Hoffschmidt, Bernhard ; Schmitz, Stefan ; Sauerborn, Markus ; Buck, Reiner ; Teufel, Edgar ; Badst{\"u}bner, Karin ; Ifland, David ; Rebholz, Christian}, series = {Proceedings of the 2nd International Conference on Energy Sustainability - 2008 : : presented ... August 10 - 14, 2008, Jacksonville, Florida, USA / sponsored by Advanced Energy Systems Division, ASME; Solar Energy Division, ASME}, journal = {Proceedings of the 2nd International Conference on Energy Sustainability - 2008 : : presented ... August 10 - 14, 2008, Jacksonville, Florida, USA / sponsored by Advanced Energy Systems Division, ASME; Solar Energy Division, ASME}, publisher = {ASME}, address = {New York, NY}, isbn = {9780791843208}, pages = {1 -- 5}, year = {2009}, language = {en} } @article{GoettscheHoffschmidtSchmitzetal.2010, author = {G{\"o}ttsche, Joachim and Hoffschmidt, Bernhard and Schmitz, Stefan and Sauerborn, Markus}, title = {Solar Concentrating Systems Using Small Mirror Arrays}, series = {Journal of solar energy engineering}, volume = {Vol. 132}, journal = {Journal of solar energy engineering}, number = {Iss. 1}, isbn = {0199-6231}, pages = {4 S.}, year = {2010}, language = {en} } @inproceedings{GoettscheHoffschmidtSchmitzetal.2008, author = {G{\"o}ttsche, Joachim and Hoffschmidt, Bernhard and Schmitz, S. and Sauerborn, Markus and Rebholz, C. and Iffland, D. and Badst{\"u}bner, R. and Buck, R. and Teufel, E.}, title = {Test of a mini-mirror array for solar concentrating systems}, 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 = {1242 -- 1250}, year = {2008}, language = {en} } @article{GoettscheHoffschmidtAlexopoulosetal.2008, author = {G{\"o}ttsche, Joachim and Hoffschmidt, Bernhard and Alexopoulos, Spiros and Funke, J. and Schwarzb{\"o}zl, P.}, title = {First Simulation Results for the Hybridization of Small Solar Power Tower Plants}, series = {EuroSun 2008 : 1st International Conference on Solar Heating, Cooling and Buildings, 2008-10-07 - 2008-10-10, Lissabon (Portugal). Vol. 1}, journal = {EuroSun 2008 : 1st International Conference on Solar Heating, Cooling and Buildings, 2008-10-07 - 2008-10-10, Lissabon (Portugal). Vol. 1}, publisher = {Sociedade Portuguesa De Energia Solar (SPES)}, address = {Lisbon}, isbn = {978-1-61782-228-5}, pages = {1299 -- 1306}, year = {2008}, language = {en} } @article{GoettscheHinschWittwer1993, author = {G{\"o}ttsche, Joachim and Hinsch, Andreas and Wittwer, Volker}, title = {Electrochromic mixed WO3-TiO2 thin films produced by sputtering and the sol-gel technique : a comparison / J. G{\"o}ttsche ; A. Hinsch ; V. Wittwer}, series = {Solar Energy Materials and Solar Cells. 31 (1993), H. 3}, journal = {Solar Energy Materials and Solar Cells. 31 (1993), H. 3}, isbn = {0927-0248}, pages = {415 -- 428}, year = {1993}, language = {en} } @article{GoettscheGoetzbergerDengleretal.1992, author = {G{\"o}ttsche, Joachim and Goetzberger, Adolf and Dengler, J. and Rommel, M. (u.a.)}, title = {A new transparently insulated, bifacially irradiated solar flat-plate collector / A. Goetzberger ; J. Dengler ; M. Rommel ; J. G{\"o}ttsche ; V. Wittwer}, series = {Solar energy. 49 (1992), H. 5}, journal = {Solar energy. 49 (1992), H. 5}, isbn = {0038-092X}, pages = {403 -- 411}, year = {1992}, language = {en} } @article{GoettscheGabryschSchilleretal.2004, author = {G{\"o}ttsche, Joachim and Gabrysch, K. and Schiller, H. and Kauert, B. and Schwarzer, Klemens}, title = {Energetic Effects of demand - controlled ventilation retrofitting in a biochemical laboratory building}, series = {AIVC publications [Elektronische Ressource] / Air Infiltration and Ventilation Centre}, journal = {AIVC publications [Elektronische Ressource] / Air Infiltration and Ventilation Centre}, publisher = {INIVE EEIG}, address = {Brussels}, pages = {50}, year = {2004}, language = {en} } @article{GoettscheGabryschDelahayeetal.2002, author = {G{\"o}ttsche, Joachim and Gabrysch, K. and Delahaye, A. and Schwarzer, Klemens}, title = {Solar-Campus Juelich - Energy performance and indoor climate}, series = {AIVC 23rd conference - EPIC 2002 AIVC (in conjunction with 3rd European Conference on Energy Performance and Indoor Climate in Buildings) - 23-26 October 2002 - Lyon - France - vol 2}, journal = {AIVC 23rd conference - EPIC 2002 AIVC (in conjunction with 3rd European Conference on Energy Performance and Indoor Climate in Buildings) - 23-26 October 2002 - Lyon - France - vol 2}, pages = {381 -- 386}, year = {2002}, language = {en} } @article{GoettscheAlexopoulosDuemmleretal.2019, author = {G{\"o}ttsche, Joachim and Alexopoulos, Spiros and D{\"u}mmler, Andreas and Maddineni, S. K.}, title = {Multi-Mirror Array Calculations With Optical Error}, pages = {1 -- 6}, year = {2019}, abstract = {The optical performance of a 2-axis solar concentrator was simulated with the COMSOL Multiphysics® software. The concentrator consists of a mirror array, which was created using the application builder. The mirror facets are preconfigured to form a focal point. During tracking all mirrors are moved simultaneously in a coupled mode by 2 motors in two axes, in order to keep the system in focus with the moving sun. Optical errors on each reflecting surface were implemented in combination with the solar angular cone of ± 4.65 mrad. As a result, the intercept factor of solar radiation that is available to the receiver was calculated as a function of the transversal and longitudinal angles of incidence. In addition, the intensity distribution on the receiver plane was calculated as a function of the incidence angles.}, language = {en} } @article{Goettsche1994, author = {G{\"o}ttsche, Joachim}, title = {Eldorado summer schools}, series = {Progress in solar energy education. 3 (1994)}, journal = {Progress in solar energy education. 3 (1994)}, isbn = {1018-5607}, pages = {31 -- 33}, year = {1994}, language = {en} } @incollection{GrossHeckenRenz1999, author = {Groß, Rolf Fritz and Hecken, M. and Renz, Ulrich}, title = {Hot gas filtration with ceramic filter candles: experimental and numerical investigations on fluid flow during element cleaning}, series = {High temperature gas cleaning. Vol. 2}, booktitle = {High temperature gas cleaning. Vol. 2}, editor = {Dittler, A. and Hemmer, G. and Kasper, G.}, publisher = {KIT Institut f{\"u}r Mechanische Verfahrenstechnik und Mechanik}, address = {Karlsruhe}, isbn = {3-9805220-1-6}, pages = {862 -- 873}, year = {1999}, abstract = {Ceramic hot gas filters are widely used in combined cycles based on pressurised fluidised beds. They fulfil most of the demands with respect to cleaning efficiency and long time durability, but their operation regarding the consumption of pulse gas and energy still has to be optimised. Experimental investigations were carried out to measure the flow field, the pressure and the gas temperature inside the filter candle during pulse jet cleaning. These results are compared with the results of a numerical procedure based on a solution of the two - dimensional conservation equations for momentum and energy. The observed difficulties handling different flow regimes like highly turbulent flow as well as Darcy flow simultaneously are discussed.}, language = {en} } @article{GorzalkaSchmiedtSchorn2021, author = {Gorzalka, Philip and Schmiedt, Jacob Estevam and Schorn, Christian}, title = {Automated Generation of an Energy Simulation Model for an Existing Building from UAV Imagery}, series = {Buildings}, volume = {11}, journal = {Buildings}, number = {9}, publisher = {MDPI}, address = {Basel}, issn = {2075-5309}, doi = {10.3390/buildings11090380}, pages = {15 Seiten}, year = {2021}, abstract = {An approach to automatically generate a dynamic energy simulation model in Modelica for a single existing building is presented. It aims at collecting data about the status quo in the preparation of energy retrofits with low effort and costs. The proposed method starts from a polygon model of the outer building envelope obtained from photogrammetrically generated point clouds. The open-source tools TEASER and AixLib are used for data enrichment and model generation. A case study was conducted on a single-family house. The resulting model can accurately reproduce the internal air temperatures during synthetical heating up and cooling down. Modelled and measured whole building heat transfer coefficients (HTC) agree within a 12\% range. A sensitivity analysis emphasises the importance of accurate window characterisations and justifies the use of a very simplified interior geometry. Uncertainties arising from the use of archetype U-values are estimated by comparing different typologies, with best- and worst-case estimates showing differences in pre-retrofit heat demand of about ±20\% to the average; however, as the assumptions made are permitted by some national standards, the method is already close to practical applicability and opens up a path to quickly estimate possible financial and energy savings after refurbishment.}, language = {en} } @inproceedings{GorzalkaDahlkeGoettscheetal.2018, author = {Gorzalka, Philip and Dahlke, Dennis and G{\"o}ttsche, Joachim and Israel, Martin and Patel, Dhruvkumar and Prahl, Christoph and Schmiedt, Jacob Estevam and Frommholz, Dirk and Hoffschmidt, Bernhard and Linkiewicz, Magdalena}, title = {Building Tomograph-From Remote Sensing Data of Existing Buildings to Building Energy Simulation Input}, series = {EBC, Annex 71, Fifth expert meeting, October 17-19, 2018, Innsbruck, Austria}, booktitle = {EBC, Annex 71, Fifth expert meeting, October 17-19, 2018, Innsbruck, Austria}, pages = {17 Seiten}, year = {2018}, language = {en} } @inproceedings{GedleSchmitzGielenetal.2022, author = {Gedle, Yibekal and Schmitz, Mark and Gielen, Hans and Schmitz, Pascal and Herrmann, Ulf and Teixeira Boura, Cristiano Jos{\´e} and Mahdi, Zahra and Caminos, Ricardo Alexander Chico and Dersch, J{\"u}rgen}, title = {Analysis of an integrated CSP-PV hybrid power plant}, 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 = {10.1063/5.0086236}, pages = {9 Seiten}, year = {2022}, abstract = {In the past, CSP and PV have been seen as competing technologies. Despite massive reductions in the electricity generation costs of CSP plants, PV power generation is - at least during sunshine hours - significantly cheaper. If electricity is required not only during the daytime, but around the clock, CSP with its inherent thermal energy storage gets an advantage in terms of LEC. There are a few examples of projects in which CSP plants and PV plants have been co-located, meaning that they feed into the same grid connection point and ideally optimize their operation strategy to yield an overall benefit. In the past eight years, TSK Flagsol has developed a plant concept, which merges both solar technologies into one highly Integrated CSP-PV-Hybrid (ICPH) power plant. Here, unlike in simply co-located concepts, as analyzed e.g. in [1] - [4], excess PV power that would have to be dumped is used in electric molten salt heaters to increase the storage temperature, improving storage and conversion efficiency. The authors demonstrate the electricity cost sensitivity to subsystem sizing for various market scenarios, and compare the resulting optimized ICPH plants with co-located hybrid plants. Independent of the three feed-in tariffs that have been assumed, the ICPH plant shows an electricity cost advantage of almost 20\% while maintaining a high degree of flexibility in power dispatch as it is characteristic for CSP power plants. As all components of such an innovative concept are well proven, the system is ready for commercial market implementation. A first project is already contracted and in early engineering execution.}, language = {en} } @inproceedings{GallAbelAhlbrinketal.2010, author = {Gall, J. and Abel, Dirk and Ahlbrink, N. and Pitz-Paal, R. and Andersson, J. and Diehl, M. and Teixeira Boura, Cristiano Jos{\´e} and Schmitz, M. and Hoffschmidt, Bernhard}, title = {Simulation and control of solar thermal power plants}, series = {International Conference on Renewable Energies and Power Quality : ICREPQ '10 : Granada 23rd - 25th March 2010}, booktitle = {International Conference on Renewable Energies and Power Quality : ICREPQ '10 : Granada 23rd - 25th March 2010}, pages = {1 -- 5}, year = {2010}, language = {en} } @inproceedings{GallAbelAhlbrinketal.2009, author = {Gall, J. and Abel, D. and Ahlbrink, N. and Andersson, J. and Diehl, M. and Pitz-Paal, R. and Schmitz, M. and Teixeira Boura, Cristiano Jos{\´e}}, title = {Optimized control of hot-gas cycle for solar thermal power plants}, series = {Proceedings of the 7th International Modelica Conference : Como, Italy, 20-22 September 2009 / Francesco Casella, ed.}, booktitle = {Proceedings of the 7th International Modelica Conference : Como, Italy, 20-22 September 2009 / Francesco Casella, ed.}, publisher = {The Modelica Association}, isbn = {978-91-7393-513-5}, pages = {490 -- 495}, year = {2009}, language = {en} } @inproceedings{FrickeZiolkoAnthrakidisetal.2012, author = {Fricke, Barbara and Ziolko, C. and Anthrakidis, Anette and Alexopoulos, Spiros and Hoffschmidt, Bernhard and Giese, F. and Dillig, M.}, title = {InnoSol - environmental aspects of the open volumetric receiver technology}, series = {30th ISES Biennial Solar World Congress 2011 : : Kassel, Germany, 28 August - 2 September 2011. Vol. 5}, booktitle = {30th ISES Biennial Solar World Congress 2011 : : Kassel, Germany, 28 August - 2 September 2011. Vol. 5}, publisher = {Curran}, address = {Red Hook, NY}, organization = {International Solar Energy Society}, pages = {3895 -- 3900}, year = {2012}, language = {en} } @inproceedings{FrickeZiolkoAnthrakidisetal.2011, author = {Fricke, Barbara and Ziolko, C. and Anthrakidis, Anette and Alexopoulos, Spiros and Hoffschmidt, Bernhard and Dillig, M. and Giese, F.}, title = {InnoSol - life cycle analysis of solar power tower plants}, 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{FrickeHoffschmidt2010, author = {Fricke, Barbara and Hoffschmidt, Bernhard}, title = {Ecobalance of a solar thermal tower power plant with volumetric receiver}, 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 = {87 -- 88}, year = {2010}, language = {en} } @inproceedings{FrantzBinderBuschetal.2020, author = {Frantz, Cathy and Binder, Matthias and Busch, Konrad and Ebert, Miriam and Heinrich, Andreas and Kaczmarkiewicz, Nadine and Schl{\"o}gl-Knothe, B{\"a}rbel and Kunze, Tobias and Schuhbauer, Christian and Stetka, Markus and Schwager, Christian and Spiegel, Michael and Teixeira Boura, Cristiano Jos{\´e} and Bauer, Thomas and Bonk, Alexander and Eisen, Stefan and Funck, Bernhard}, title = {Basic Engineering of a High Performance Molten Salt Tower Receiver System}, series = {Solar Paces 2020}, booktitle = {Solar Paces 2020}, pages = {1 -- 10}, year = {2020}, language = {en} }