@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}
}
@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}
}
@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{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{AchenbachGeimerLynenetal.2012,
  author    = {Achenbach, Timm and Geimer, Konstantin and Lynen, Arthur and G{\"o}ttsche, Joachim and Hoffschmidt, Bernhard},
  title     = {Simulation of thermo-mechanical processes in open volumetric absorber modules},
  series = {SolarPaces 2012 : concentrating solar power and chemical energy systems : Sept. 11 - 14 2012, Marrakech, Marokko},
  booktitle = {SolarPaces 2012 : concentrating solar power and chemical energy systems : Sept. 11 - 14 2012, Marrakech, Marokko},
  pages     = {1 -- 8},
  year      = {2012},
  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}
}
@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}
}
@inproceedings{AlexopoulosKluczkaVaessenetal.2012,
  author    = {Alexopoulos, Spiros and Kluczka, Sven and Vaeßen, Christiane and Roeb, M. and Neises, M.},
  title     = {Scenario development for efficient methanol production using CO2 and solar energy},
  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 99},
  year      = {2012},
  language  = {en}
}
@inproceedings{BaumannTeixeiraBouraEcksteinetal.2012,
  author    = {Baumann, Torsten and Teixeira Boura, Cristiano Jos{\´e} and Eckstein, Julian and Dabrowski, Jan and G{\"o}ttsche, Joachim and Hoffschmidt, Bernhard and Schmitz, Stefan and Zunft, Stefan},
  title     = {Properties of bulk materials for high-temperature air-sand heat exchangers},
  series = {30th ISES Biennial Solar World Congress 2011 : Kassel, Germany, 28 August - 2 September 2011. Vol. 2},
  booktitle = {30th ISES Biennial Solar World Congress 2011 : Kassel, Germany, 28 August - 2 September 2011. Vol. 2},
  publisher = {Curran},
  address   = {Red Hook, NY},
  organization    = {International Solar Energy Society},
  isbn      = {978-1-61839-364-7},
  pages     = {1270 -- 1278},
  year      = {2012},
  language  = {en}
}
@inproceedings{AlexopoulosRauHoffschmidtetal.2012,
  author    = {Alexopoulos, Spiros and Rau, Christoph and Hoffschmidt, Bernhard and Breitbach, Gerd and Latzke, Markus},
  title     = {Modelling and validation of a transient heat recovery steam generator of the solar tower power plant Juelich},
  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 97},
  year      = {2012},
  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}
}
@inproceedings{AlexopoulosHoffschmidtRauetal.2012,
  author    = {Alexopoulos, Spiros and Hoffschmidt, Bernhard and Rau, Christoph and Sattler, Johannes Christoph},
  title     = {Simulation of hybrid solar tower power plants},
  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     = {4044 -- 4050},
  year      = {2012},
  language  = {en}
}
@article{VieiradaSilvaSchwarzerHoffschmidtetal.2013,
  author    = {Vieira da Silva, Maria Eugenia and Schwarzer, Klemens and Hoffschmidt, Bernhard and Pinheiro Rodrigues, Frederico and Schwarzer, Tarik and Costa Rocha, Paulo Alexandre},
  title     = {Mass transfer correlation for evaporation-condensation thermal process in the range of 70 °C-95 °C},
  series = {Renewable energy},
  volume    = {Vol. 53},
  journal   = {Renewable energy},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1879-0682 (E-Journal); 0960-1481 (Print)},
  pages     = {174 -- 179},
  year      = {2013},
  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{AchenbachBoschBreitbachetal.2013,
  author    = {Achenbach, Timm and Bosch, Timo and Breitbach, Gerd and G{\"o}ttsche, Joachim and Sauerborn, Markus},
  title     = {Theoretical and experimental investigations regarding open volumetric receivers of CRS},
  series = {Energy procedia : proceedings of the SolarPACES 2013 International Conference},
  volume    = {Vol. 49},
  booktitle = {Energy procedia : proceedings of the SolarPACES 2013 International Conference},
  issn      = {1876-6102},
  pages     = {1259 -- 1268},
  year      = {2013},
  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}
}
@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{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}
}
@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}
}
@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}
}