@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{AringhoffGeyerHerrmannetal.2002,
  author    = {Aringhoff, R. and Geyer, Michael and Herrmann, Ulf and Kistner, Rainer and Nava, P. and Osuna, R.},
  title     = {AndaSol : 50MW Solar Plants with 9 Hour Storage for Southern Spain},
  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     = {37 -- 42},
  year      = {2002},
  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{AnthrakidisHerrmannSchornetal.2015,
  author    = {Anthrakidis, Anette and Herrmann, Ulf and Schorn, Christian and Schwarzer, Klemens and Wedding, Philipp and Weis, Fabian},
  title     = {Development and Testing of a Novel Method for the Determination of the Efficiency of Concentrating Solar Thermal Collectors},
  series = {Conference Proceedings Solar World Congress 2015, Daegu, Korea, 08 - 12 November 2015},
  booktitle = {Conference Proceedings Solar World Congress 2015, Daegu, Korea, 08 - 12 November 2015},
  pages     = {9 Seiten},
  year      = {2015},
  language  = {en}
}
@inproceedings{TeixeiraBouraNiederwestbergMcLeodetal.2016,
  author    = {Teixeira Boura, Cristiano Jos{\´e} and Niederwestberg, Stefan and McLeod, Jacqueline and Herrmann, Ulf and Hoffschmidt, Bernhard},
  title     = {Development of heat exchanger for high temperature energy storage with bulk materials},
  series = {AIP Conference Proceedings},
  volume    = {1734},
  booktitle = {AIP Conference Proceedings},
  number    = {1},
  doi       = {10.1063/1.4949106},
  pages     = {050008-1 -- 050008-7},
  year      = {2016},
  language  = {en}
}
@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{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}
}
@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{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}
}
@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{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{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{SchwagerTeixeiraBouraFleschetal.2019,
  author    = {Schwager, Christian and Teixeira Boura, Cristiano Jos{\´e} and Flesch, Robert and Alexopoulos, Spiros and Herrmann, Ulf},
  title     = {Improved efficiency prediction of a molten salt receiver based on dynamic cloud passage simulation},
  series = {AIP Conference Proceedings},
  volume    = {2126},
  booktitle = {AIP Conference Proceedings},
  number    = {1},
  isbn      = {978-0-7354-1866-0},
  doi       = {10.1063/1.5117566},
  pages     = {030054-1 -- 030054-8},
  year      = {2019},
  language  = {en}
}
@inproceedings{BlankeDringVonteinetal.2018,
  author    = {Blanke, Tobias and Dring, Bernd and Vontein, Marius and Kuhnhenne, Markus},
  title     = {Climate Change Mitigation Potentials of Vertical Building Integrated Photovoltaic},
  series = {8th International Workshop on Integration of Solar Power into Power Systems : 16-17 October 2018, Stockholm, Sweden},
  booktitle = {8th International Workshop on Integration of Solar Power into Power Systems : 16-17 October 2018, Stockholm, Sweden},
  pages     = {1 -- 7},
  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{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{ZahraPhaniSrujanCaminosetal.2022,
  author    = {Zahra, Mahdi and Phani Srujan, Merige and Caminos, Ricardo Alexander Chico and Schmitz, Pascal and Herrmann, Ulf and Teixeira Boura, Cristiano Jos{\´e} and Schmitz, Mark and Gielen, Hans and Gedle, Yibekal and Dersch, J{\"u}rgen},
  title     = {Modeling the thermal behavior of solar salt in electrical resistance heaters for the application in PV-CSP hybrid power plants},
  series = {SOLARPACES 2020},
  booktitle = {SOLARPACES 2020},
  number    = {2445 / 1},
  publisher = {AIP conference proceedings / American Institute of Physics},
  address   = {Melville, NY},
  isbn      = {978-0-7354-4195-8},
  issn      = {1551-7616 (online)},
  doi       = {10.1063/5.0086268},
  pages     = {9 Seiten},
  year      = {2022},
  abstract  = {Concentrated Solar Power (CSP) systems are able to store energy cost-effectively in their integrated thermal energy storage (TES). By intelligently combining Photovoltaics (PV) systems with CSP, a further cost reduction of solar power plants is expected, as well as an increase in dispatchability and flexibility of power generation. PV-powered Resistance Heaters (RH) can be deployed to raise the temperature of the molten salt hot storage from 385 °C up to 565 °C in a Parabolic Trough Collector (PTC) plant. To avoid freezing and decomposition of molten salt, the temperature distribution in the electrical resistance heater is investigated in the present study. For this purpose, a RH has been modeled and CFD simulations have been performed. The simulation results show that the hottest regions occur on the electric rod surface behind the last baffle. A technical optimization was performed by adjusting three parameters: Shell-baffle clearance, electric rod-baffle clearance and number of baffles. After the technical optimization was carried out, the temperature difference between the maximum temperature and the average outlet temperature of the salt is within the acceptable limits, thus critical salt decomposition has been avoided. Additionally, the CFD simulations results were analyzed and compared with results obtained with a one-dimensional model in Modelica.},
  language  = {en}
}
@inproceedings{CaminosSchmitzAttietal.2022,
  author    = {Caminos, Ricardo Alexander Chico and Schmitz, Pascal and Atti, Vikrama and Mahdi, Zahra and Teixeira Boura, Cristiano Jos{\´e} and Sattler, Johannes Christoph and Herrmann, Ulf and Hilger, Patrick and Dieckmann, Simon},
  title     = {Development of a micro heliostat and optical qualification assessment with a 3D laser scanning method},
  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       = {10.1063/5.0086262},
  pages     = {8 Seiten},
  year      = {2022},
  abstract  = {The Solar-Institut J{\"u}lich (SIJ) and the companies Hilger GmbH and Heliokon GmbH from Germany have developed a small-scale cost-effective heliostat, called "micro heliostat". Micro heliostats can be deployed in small-scale concentrated solar power (CSP) plants to concentrate the sun's radiation for electricity generation, space or domestic water heating or industrial process heat. In contrast to conventional heliostats, the special feature of a micro heliostat is that it consists of dozens of parallel-moving, interconnected, rotatable mirror facets. The mirror facets array is fixed inside a box-shaped module and is protected from weathering and wind forces by a transparent glass cover. The choice of the building materials for the box, tracking mechanism and mirrors is largely dependent on the selected production process and the intended application of the micro heliostat. Special attention was paid to the material of the tracking mechanism as this has a direct influence on the accuracy of the micro heliostat. The choice of materials for the mirror support structure and the tracking mechanism is made in favor of plastic molded parts. A qualification assessment method has been developed by the SIJ in which a 3D laser scanner is used in combination with a coordinate measuring machine (CMM). For the validation of this assessment method, a single mirror facet was scanned and the slope deviation was computed.},
  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}
}