@inproceedings{GallAbelAhlbrinketal.2009, author = {Gall, Jan and Abel, Dirk and Ahlbrink, Nils and Andersson, Joel A. E. and Diehl, Moritz and Pitz-Paal, Robert and Schmitz, Mark 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{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{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{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} } @inproceedings{SattlerAttiAlexopoulosetal.2022, author = {Sattler, Johannes Christoph and Atti, Vikrama Naga Babu 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 2022 conference proceedings}, booktitle = {SolarPACES 2022 conference proceedings}, number = {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{DuranParedesMottaghyHerrmannetal.2020, author = {Duran Paredes, Ludwin and Mottaghy, Darius and Herrmann, Ulf and Groß, Rolf Fritz}, title = {Online ground temperature and soil moisture monitoring of a shallow geothermal system with non-conventional components}, series = {EGU General Assembly 2020}, booktitle = {EGU General Assembly 2020}, year = {2020}, abstract = {We present first results from a newly developed monitoring station for a closed loop geothermal heat pump test installation at our campus, consisting of helix coils and plate heat exchangers, as well as an ice-store system. There are more than 40 temperature sensors and several soil moisture content sensors distributed around the system, allowing a detailed monitoring under different operating conditions.In the view of the modern development of renewable energies along with the newly concepts known as Internet of Things and Industry 4.0 (high-tech strategy from the German government), we created a user-friendly web application, which will connect the things (sensors) with the open network (www). Besides other advantages, this allows a continuous remote monitoring of the data from the numerous sensors at an arbitrary sampling rate.Based on the recorded data, we will also present first results from numerical simulations, taking into account all relevant heat transport processes.The aim is to improve the understanding of these processes and their influence on the thermal behavior of shallow geothermal systems in the unsaturated zone. This will in turn facilitate the prediction of the performance of these systems and therefore yield an improvement in their dimensioning when designing a specific shallow geothermal installation.}, language = {en} } @inproceedings{SattlerChicoCaminosUerlingsetal.2020, author = {Sattler, Johannes Christoph and Chico Caminos, Ricardo Alexander 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 Naga Babu 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}, abstract = {As part of the transnational research project EDITOR, a parabolic trough collector system (PTC) with concrete thermal energy storage (C-TES) was installed and commissioned in Limassol, Cyprus. The system is located on the premises of the beverage manufacturer KEAN Soft Drinks Ltd. and its function is to supply process steam for the factory's pasteurisation process [1]. Depending on the factory's seasonally varying capacity for beverage production, the solar system delivers between 5 and 25 \% of the total steam demand. In combination with the C-TES, the solar plant can supply process steam on demand before sunrise or after sunset. Furthermore, the C-TES compensates the PTC during the day in fluctuating weather conditions. The parabolic trough collector as well as the control and oil handling unit is designed and manufactured by Protarget AG, Germany. The C-TES is designed and produced by CADE Soluciones de Ingenier{\´i}a, S.L., Spain. In the focus of this paper is the description of the operational experience with the PTC, C-TES and boiler during the commissioning and operation phase. Additionally, innovative optimisation measures are presented.}, language = {en} }