@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}
}
@article{DammSauerbornFendetal.2017,
  author    = {Damm, Marc Andr{\´e} and Sauerborn, Markus and Fend, Thomas and Herrmann, Ulf},
  title     = {Optimisation of a urea selective catalytic reduction system with a coated ceramic mixing element},
  series = {Journal of ceramic science and technology},
  volume    = {8},
  journal   = {Journal of ceramic science and technology},
  number    = {1},
  publisher = {G{\"o}ller},
  address   = {Baden-Baden},
  isbn      = {2190-9385 (Print)},
  issn      = {2190-9385 (Online)},
  doi       = {10.4416/JCST2016-00056},
  pages     = {19 -- 24},
  year      = {2017},
  language  = {en}
}
@article{RegerKuhnhenneHachuletal.2019,
  author    = {Reger, Vitali and Kuhnhenne, Markus and Hachul, Helmut and D{\"o}ring, Bernd and Blanke, Tobias and G{\"o}ttsche, Joachim},
  title     = {Plusenergiegeb{\"a}ude 2.0 in Stahlleichtbauweise},
  series = {Stahlbau},
  volume    = {88},
  journal   = {Stahlbau},
  number    = {6},
  publisher = {Ernst \& Sohn},
  address   = {Berlin},
  issn      = {1437-1049 (E-journal), 0038-9145 (print)},
  doi       = {10.1002/stab.201900034},
  pages     = {522 -- 528},
  year      = {2019},
  language  = {de}
}
@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{HerrmannNava2005,
  author    = {Herrmann, Ulf and Nava, P.},
  title     = {Die Strahlung der Sonne einfangen},
  series = {DLR-Nachrichten / Deutsches Zentrum f{\"u}r Luft- und Raumfahrt},
  volume    = {109},
  journal   = {DLR-Nachrichten / Deutsches Zentrum f{\"u}r Luft- und Raumfahrt},
  number    = {Sonderheft Solarforschung},
  issn      = {0937-0420},
  pages     = {34 -- 37},
  year      = {2005},
  language  = {de}
}
@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}
}
@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}
}
@inproceedings{SattlerChicoCaminosAttietal.2020,
  author    = {Sattler, Johannes Christoph and Chico Caminos, Ricardo Alexander and Atti, Vikrama Naga Babu 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}
}
@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},
  publisher = {Kavala Institute of Technology},
  address   = {Kavala},
  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}
}
@article{GrossBergerGross2003,
  author    = {Groß, Rolf Fritz and Berger, J{\"o}rg and Groß, H.},
  title     = {Geb{\"a}udeautomation - Betriebsdatenerfassung und Geb{\"a}udeleittechnik im Klartext},
  series = {HLH. Heizung, L{\"u}ftung/Klima, Haustechnik},
  volume    = {54},
  journal   = {HLH. Heizung, L{\"u}ftung/Klima, Haustechnik},
  number    = {2},
  publisher = {Springer},
  address   = {D{\"u}sseldorf},
  issn      = {1436-5103},
  pages     = {81},
  year      = {2003},
  language  = {de}
}
@incollection{AtmaneHirechKassmietal.2020,
  author    = {Atmane, Ilias and Hirech, Kamal and Kassmi, K. and Mahdi, Zahra and Alexopoulos, Spiros and Schwarzer, Klemens and Chayeb, H. and Bachiri, Najib},
  title     = {Design and realization of a pilot solar desalination plant in Douar El Hamri in the province of Berkane (Morocco)},
  series = {Sustainable entrepreneurship, renewable energy-based projects, and digitalization},
  booktitle = {Sustainable entrepreneurship, renewable energy-based projects, and digitalization},
  editor    = {Omrane, Amina and Kassmi, Khalil and Akram, Muhammad Wasim and Khanna, Ashish and Mostafiz, Imtiaz},
  publisher = {CRC Press},
  address   = {Boca Raton, Fa.},
  isbn      = {9781000292541 (E-Book)},
  pages     = {18 Seiten},
  year      = {2020},
  abstract  = {Producing fresh water from saline water has become one of the most difficult challenges to overcome especially with the high demand and shortage of fresh water. In this context, as part of a collaboration with Germany, the authors propose a design and implementation of a pilot multi-stage solar desalination system (MSD), remotely controlled, at Douar Al Hamri in the rural town of Boughriba in the province of Berkane, Morocco. More specifically, they present their contribution on the remote control and supervision system, which makes the functioning of the MSD system reliable and guarantees the production of drinking water for the population of Douar. The results obtained show that the electronic cards and computer communication software implemented allow the acquisition of all electrical (currents, voltages, powers, yields), thermal (temperatures of each stage), and meteorological (irradiance and ambient temperature), remote control and maintenance (switching on, off, data transfer). By comparing with the literature carried out in the field of solar energy, the authors conclude that the MSD and electronic desalination systems realized during this work represent a contribution in terms of the reliability and durability of providing drinking water in rural and urban areas.},
  language  = {en}
}
@article{GrossBerger2005,
  author    = {Groß, Rolf Fritz and Berger, J{\"o}rg},
  title     = {Quo Vadis - Ausblick in die Geb{\"a}udeleittechnik der Zukunft},
  series = {HLH. Heizung, L{\"u}ftung/Klima, Haustechnik},
  volume    = {56},
  journal   = {HLH. Heizung, L{\"u}ftung/Klima, Haustechnik},
  number    = {1},
  publisher = {Springer},
  address   = {D{\"u}sseldorf},
  issn      = {1436-5103},
  pages     = {39 -- 41},
  year      = {2005},
  abstract  = {Auf dem Weg zum vernetzten Haus stoßen Hersteller und Planer, insbesondere im privaten Wohnungsbau, zur Zeit noch auf erhebliche Widerst{\"a}nde bei der Durchdringung des Marktes.},
  language  = {de}
}
@techreport{GhinaiyaLehmannGoettsche2022,
  author    = {Ghinaiya, Jagdishkumar and Lehmann, Thomas Martin and G{\"o}ttsche, Joachim},
  title     = {LOCAL+ - ein kreislauff{\"a}higer Holzmodulbau mit nachhaltigem Energie- und Wohnraumkonzept},
  series = {Bauphysik},
  volume    = {44},
  journal   = {Bauphysik},
  number    = {3},
  publisher = {Ernst \& Sohn},
  address   = {Hoboken},
  issn      = {0171-5445 (Print)},
  doi       = {10.1002/bapi.202200010},
  pages     = {136 -- 142},
  year      = {2022},
  abstract  = {Mit dem Beitrag des Teams der FH Aachen zum SDE 21/22 wird im Projekt LOCAL+ ein kreislauff{\"a}higer Holzmodulbau mit einem innovativen Wohnraumkonzept geplant und umgesetzt. Ziel dieses Konzeptes ist die Verringerung des stetig steigenden Wohnfl{\"a}chenbedarfs durch ein Raum-in-Raum Konzept. Geb{\"a}udetechnisch wird in dem Projekt nicht nur das Einzelgeb{\"a}ude betrachtet, sondern unter Ber{\"u}cksichtigung des Geb{\"a}udebestandes wird f{\"u}r das Quartier ein innovatives und nachhaltiges Energiekonzept entwickelt. Ein zentrales Wasserstoffsystem ist f{\"u}r ein Quartier geplant, um den Stromverbrauch aus dem Netz im Winter zu reduzieren. Zentraler Bestandteil des TGA-Konzepts ist ein unterirdischer Eisspeicher, eine PVT und eine W{\"a}rmepumpe mit intelligenter Regelstrategie. Ein Teil des neuen Geb{\"a}udes (Design Challenge DC) wird in Wuppertal als Hausdemonstrationseinheit (HDU) pr{\"a}sentiert. Eine hygrothermische Simulation der HDU wurde mit der WUFI-Software durchgef{\"u}hrt. Da im Innenraum Lehmmodule und -platten als Feuchtigkeitspuffer verwendet werden, spielen die Themen Feuchtigkeit, Holzf{\"a}ule und Schimmelwachstum eine wichtige Rolle.},
  language  = {de}
}
@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    = {132},
  journal   = {Journal of solar energy engineering},
  number    = {1},
  publisher = {ASME},
  address   = {New York},
  issn      = {0199-6231},
  doi       = {10.1115/1.4000332},
  pages     = {4 Seiten},
  year      = {2010},
  abstract  = {The cost of solar tower power plants is dominated by the heliostat field making up roughly 50\% of investment costs. Classical heliostat design is dominated by mirrors brought into position by steel structures and drives that guarantee high accuracies under wind loads and thermal stress situations. A large fraction of costs is caused by the stiffness requirements of the steel structure, typically resulting in ~ 20 kg/m² steel per mirror area. The typical cost figure of heliostats (figure mentioned by Solucar at Solar Paces Conference, Seville, 2006) is currently in the area of 150 €/m² caused by the increasing price of the necessary raw materials. An interesting option to reduce costs lies in a heliostat design where all moving parts are protected from wind loads. In this way, drives and mechanical layout may be kept less robust, thereby reducing material input and costs. In order to keep the heliostat at an appropriate size, small mirrors (around 10x10 cm²) have to be used, which are placed in a box with a transparent cover. Innovative drive systems are developed in order to obtain a cost-effective design. A 0,5x0,5 m² demonstration unit will be constructed. Tests of the unit are carried out with a high-precision artificial sun unit that imitates the sun's path with an accuracy of less than 0.5 mrad and creates a beam of parallel light with a divergence of less than 4 mrad.},
  language  = {en}
}