TY - JOUR A1 - Alexopoulos, Spiros T1 - Simulation model for the transient process behaviour of solar aluminium recycling in a rotary kiln JF - Applied Thermal Engineering Y1 - 2015 U6 - https://doi.org/10.1016/j.applthermaleng.2015.01.007 SN - 1359-4311 N1 - Autor im Original: Spiridon O. Alexopoulos VL - 78 SP - 387 EP - 396 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Alexopoulos, Spiros T1 - Biogas systems: basics, biogas multifunction, principle of fermentation and hybrid application with a solar tower for the treatment of waste animal manure JF - Journal of Engineering Science and Technology Review N2 - 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 Y1 - 2012 SN - 1791-2377 N1 - Special Issue on Renewable Energy Systems VL - 5 IS - 4 SP - 48 EP - 55 ER - TY - JOUR A1 - Göttsche, Joachim A1 - Alexopoulos, Spiros A1 - Dümmler, Andreas A1 - Maddineni, S. K. T1 - Multi-Mirror Array Calculations With Optical Error N2 - The optical performance of a 2-axis solar concentrator was simulated with the COMSOL Multiphysics® software. The concentrator consists of a mirror array, which was created using the application builder. The mirror facets are preconfigured to form a focal point. During tracking all mirrors are moved simultaneously in a coupled mode by 2 motors in two axes, in order to keep the system in focus with the moving sun. Optical errors on each reflecting surface were implemented in combination with the solar angular cone of ± 4.65 mrad. As a result, the intercept factor of solar radiation that is available to the receiver was calculated as a function of the transversal and longitudinal angles of incidence. In addition, the intensity distribution on the receiver plane was calculated as a function of the incidence angles. KW - solar process heat KW - concentrating collector KW - raytracing KW - point-focussing system Y1 - 2019 SP - 1 EP - 6 ER - TY - JOUR A1 - Göttsche, Joachim A1 - Russ, Christel T1 - Energieversorgung in Niedrigstenergie-Neubauwohnungen / Christel Russ ; Joachim Göttsche JF - Wärme und Kälte - Energie aus Sonne und Erde : Jahrestagung des Forschungsverbunds Sonnenenergie in Kooperation mit der Landesinitiative Zukunftsenergie NRW / Stadermann, Gerd, Hrsg. Y1 - 2005 SP - 93 EP - 98 PB - Forschungsverbund Sonnenenergie CY - Berlin ER - TY - JOUR A1 - Kluczka, Sven A1 - Eckstein, Julian A1 - Alexopoulos, Spiros A1 - Vaeßen, Christiane A1 - Roeb, Martin T1 - Process simulation for solar steam and dry reforming JF - Energy procedia : Proceedings of the SolarPACES 2013 International Conference N2 - In co-operation with the German Aerospace Center, the Solar-Institut Jülich 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. Y1 - 2014 U6 - https://doi.org/10.1016/j.egypro.2014.03.092 SN - 1876-6102 (E-Journal) VL - 49 SP - 850 EP - 859 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Göttsche, Joachim A1 - Hinsch, Andreas A1 - Wittwer, Volker T1 - Electrochromic mixed WO3-TiO2 thin films produced by sputtering and the sol-gel technique : a comparison / J. Göttsche ; A. Hinsch ; V. Wittwer JF - Solar Energy Materials and Solar Cells. 31 (1993), H. 3 Y1 - 1993 SN - 0927-0248 SP - 415 EP - 428 ER - TY - JOUR A1 - Göttsche, Joachim A1 - Tamme, Rainer A1 - Nunez, Thomas T1 - Speicherung für Hochtemperaturwärme / Rainer Tamme ; Joachim Göttsche ; Thomas Nunez JF - Wärme und Kälte - Energie aus Sonne und Erde : Jahrestagung des Forschungsverbunds Sonnenenergie in Kooperation mit der Landesinitiative Zukunftsenergie NRW / Stadermann, Gerd, Hrsg. Y1 - 2005 SP - 126 EP - 131 PB - Forschungsverbund Sonnenenergie CY - Berlin ER - TY - JOUR A1 - Herrmann, Ulf A1 - Kelly, Bruce A1 - Price, Henry T1 - Two Tank Molten Salt Storage for Parabolic Trough Solar Power Plants JF - Energy : the international journal Y1 - 2002 U6 - https://doi.org/10.1016/S0360-5442(03)00193-2 SN - 0360-5442 N1 - SolarPACES 2002, Zürich, Switzerland, 4–6 September 2002 VL - 29 IS - 5-6 (Special Issue SolarPaces) SP - 883 EP - 893 ER - TY - JOUR A1 - Herrmann, Ulf A1 - Schwarzenbart, Marc A1 - Dittmann-Gabriel, Sören A1 - May, Martin T1 - Hochtemperatur-Wärmespeicher für die Strom- und Wärmewende JF - Solarzeitalter : Politik, Kultur und Ökonomie erneuerbarer Energien Y1 - 2019 SN - 0937-3802 VL - 31 IS - 2 SP - 18 EP - 23 ER - TY - JOUR A1 - Dersch, Jürgen A1 - Geyer, Michael A1 - Herrmann, Ulf A1 - Jones, Scott A. A1 - Kelly, Bruce A1 - Kistner, Rainer A1 - Ortmanns, Winfried A1 - Pitz-Paal, Robert A1 - Price, Henry T1 - Trough integration into power plants—a study on the performance and economy of integrated solar combined cycle systems JF - Energy : the international journal Y1 - 2004 U6 - https://doi.org/10.1016/S0360-5442(03)00199-3 SN - 0360-5442 N1 - SolarPACES 2002, Zürich, Switzerland, 4–6 September 2002 VL - 29 IS - 5-6 (Special Issue SolarPaces) SP - 947 EP - 959 ER -