@article{AlexopoulosHoffschmidt2017,
  author    = {Alexopoulos, Spiros and Hoffschmidt, Bernhard},
  title     = {Advances in solar tower technology},
  series = {Wiley interdisciplinary reviews : Energy and Environment : WIREs},
  volume    = {6},
  journal   = {Wiley interdisciplinary reviews : Energy and Environment : WIREs},
  number    = {1},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {2041-840X},
  doi       = {10.1002/wene.217},
  pages     = {1 -- 19},
  year      = {2017},
  language  = {en}
}
@inproceedings{VaessenAlexopoulosKluczkaetal.2011,
  author    = {Vaeßen, Christiane and Alexopoulos, Spiros and Kluczka, Sven and Sattler, Johannes Christoph and Roeb, M. and Neises, M. and Abdellatif, T.},
  title     = {Analyse der Verfahren zur solaren Methanolproduktion aus CO2},
  series = {Forschung und Entwicklung f{\"u}r solarthermische Kraftwerke : 14. K{\"o}lner Sonnenkolloquium Mittwoch, 13. Juli 2011, im Auditorium des Campus J{\"u}lich der FH Aachen : Kurzfassungen der Vortr{\"a}ge und Poster},
  booktitle = {Forschung und Entwicklung f{\"u}r solarthermische Kraftwerke : 14. K{\"o}lner Sonnenkolloquium Mittwoch, 13. Juli 2011, im Auditorium des Campus J{\"u}lich der FH Aachen : Kurzfassungen der Vortr{\"a}ge und Poster},
  publisher = {DLR},
  address   = {K{\"o}ln},
  pages     = {2 S.},
  year      = {2011},
  language  = {de}
}
@inproceedings{BreitbachAlexopoulosMayetal.2019,
  author    = {Breitbach, Gerd and Alexopoulos, Spiros and May, Martin and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf},
  title     = {Analysis of volumetric solar radiation absorbers made of wire meshes},
  series = {AIP Conference Proceedings},
  volume    = {2126},
  booktitle = {AIP Conference Proceedings},
  issn      = {0094243X},
  doi       = {10.1063/1.5117521},
  pages     = {030009-1 -- 030009-6},
  year      = {2019},
  language  = {en}
}
@article{Alexopoulos2012,
  author    = {Alexopoulos, Spiros},
  title     = {Biogas systems: basics, biogas multifunction, principle of fermentation and hybrid application with a solar tower for the treatment of waste animal manure},
  series = {Journal of Engineering Science and Technology Review},
  volume    = {5},
  journal   = {Journal of Engineering Science and Technology Review},
  number    = {4},
  issn      = {1791-2377},
  pages     = {48 -- 55},
  year      = {2012},
  abstract  = {Two of the main environmental problems of today's society are the continuously increasing production of organic wastes as well as the increase of carbon dioxide in the atmosphere and the related green house effect. A way to solve these problems is the production of biogas. Biogas is a combustible gas consisting of methane, carbon dioxide and small amounts of other gases and trace elements. Production of biogas through anaerobic digestion of animal manure and slurries as well as of a wide range of digestible organic wastes and agricultural residues, converts these substrates into electricity and heat and offers a natural fertiliser for agriculture. The microbiological process of decomposition of organic matter, in the absence of oxygen takes place in reactors, called digesters. Biogas can be used as a fuel in a gas turbine or burner and can be used in a hybrid solar tower system offering a solution for waste treatment of agricultural and animal residues. A solar tower system consists of a heliostat field, which concentrates direct solar irradiation on an open volumetric central receiver. The receiver heats up ambient air to temperatures of around 700°C. The hot air's heat energy is transferred to a steam Rankine cycle in a heat recovery steam generator (HRSG). The steam drives a steam turbine, which in turn drives a generator for producing electricity. In order to increase the operational hours of a solar tower power plant, a heat storage system and/ or hybridization may be considered. The advantage of solar-fossil hybrid power plants, compared to solar-only systems, lies in low additional investment costs due to an adaptable solar share and reduced technical and economical risks. On sunny days the hybrid system operates in a solar-only mode with the central receiver and on cloudy days and at night with the gas turbine only. As an alternative to methane gas, environmentally neutral biogas can be used for operating the gas turbine. Hence, the hybrid system is operated to 100\% from renewable energy sources},
  language  = {en}
}
@incollection{Alexopoulos2013,
  author    = {Alexopoulos, Spiros},
  title     = {Biomass technology and bio-fuels: Heating/cooling and power},
  series = {Renewable energy systems : theory, innovations, and intelligent applications / eds.: Socrates Kaplanis and Eleni Kaplani},
  booktitle = {Renewable energy systems : theory, innovations, and intelligent applications / eds.: Socrates Kaplanis and Eleni Kaplani},
  publisher = {Nova Science Publ.},
  address   = {Hauppauge, NY},
  isbn      = {9781624177415},
  pages     = {501 -- 523},
  year      = {2013},
  language  = {en}
}
@inproceedings{AlexopoulosHoffschmidtRauetal.2011,
  author    = {Alexopoulos, Spiros and Hoffschmidt, Bernhard and Rau, Christoph and Sattler, Johannes, Christoph},
  title     = {Choice of solar share of a hybrid power plant of a central receiver system and a biogas plant in dependency of the geographical latitude},
  series = {World Renewable Energy Congress-Sweden : 8 -13 May, 2011, Link{\"o}ping, Sweden / ed.: Bahram Moshfegh},
  booktitle = {World Renewable Energy Congress-Sweden : 8 -13 May, 2011, Link{\"o}ping, Sweden / ed.: Bahram Moshfegh},
  publisher = {Univ. Electronic Pr.},
  address   = {Link{\"o}ping},
  isbn      = {9789173930703},
  pages     = {3710 -- 3717},
  year      = {2011},
  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{AlexopoulosHoffschmidtRau2011,
  author    = {Alexopoulos, Spiros and Hoffschmidt, Bernhard and Rau, Christoph},
  title     = {Comparison of steady-state and transient simulations for solar tower power plants with open-volumetric receiver},
  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{AlexopoulosBreitbachHoffschmidtetal.2008,
  author    = {Alexopoulos, Spiros and Breitbach, Gerd and Hoffschmidt, Bernhard and Stobbe, P.},
  title     = {Computational fluid flow of porous resic ceramic filtering modules and optimization of the channel edge form geometry},
  series = {Proceedings : April 14 - 18, 2008, Leipzig, Germany / hosted by VDI, Society for Chemical and Process Engineering . Vol 2},
  journal   = {Proceedings : April 14 - 18, 2008, Leipzig, Germany / hosted by VDI, Society for Chemical and Process Engineering . Vol 2},
  publisher = {Filtech Exhibitions},
  address   = {Meerbusch},
  pages     = {300 -- 304},
  year      = {2008},
  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{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.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}
}
@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{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{SattlerChicoCaminosAttietal.2020,
  author    = {Sattler, Johannes Christoph and Chico Caminos, Ricardo Alexander and Atti, Vikrama Nagababu and {\"U}rlings, Nicolas and Dutta, Siddharth and Ruiz, Victor and Kalogirou, Soteris and Ktistis, Panayiotis and Agathokleous, Rafaela and Alexopoulos, Spiros and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf},
  title     = {Dynamic simulation tool for a performance evaluation and sensitivity study of a parabolic trough collector system with concrete thermal energy storage},
  series = {AIP Conference Proceedings 2303},
  booktitle = {AIP Conference Proceedings 2303},
  publisher = {American Institute of Physics},
  address   = {Melville, NY},
  issn      = {0094-243X},
  doi       = {10.1063/5.0029277},
  pages     = {160004},
  year      = {2020},
  language  = {de}
}
@techreport{HoffschmidtAlexopoulos2011,
  author    = {Hoffschmidt, Bernhard and Alexopoulos, Spiros},
  title     = {Entwicklung der Designvoraussetzungen f{\"u}r ein hybrides Solarthermisches Kraftwerk : Kurztitel: HybSol ; Abschlussbericht ; Berichtszeitraum: 01.03.2007 - 31.10.2010 ; [F{\"o}rderprogramm: FHprofUnt]},
  publisher = {Solar-Inst.},
  address   = {J{\"u}lich},
  pages     = {114 S.},
  year      = {2011},
  language  = {de}
}
@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}
}
@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}
}
@inproceedings{BreitbachAlexopoulosHoffschmidt2007,
  author    = {Breitbach, Gerd and Alexopoulos, Spiros and Hoffschmidt, Bernhard},
  title     = {Fluid flow in porous ceramic multichannel crossflower filter modules},
  publisher = {COMSOL Inc.},
  address   = {Burlington, Mass.},
  pages     = {5 S.},
  year      = {2007},
  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}
}