TY - JOUR A1 - Göttsche, Joachim A1 - Hoffschmidt, Bernhard A1 - Schmitz, Stefan A1 - Sauerborn, Markus T1 - Solar Concentrating Systems Using Small Mirror Arrays / Göttsche, Joachim ; Hoffschmidt, Bernhard ; Schmitz, Stefan ; Sauerborn, Markus ; Buck, Reiner ; Teufel, Edgar ; Badstübner, Karin ; Ifland, David ; Rebholz, Christian JF - Proceedings of the 2nd International Conference on Energy Sustainability - 2008 : : presented ... August 10 - 14, 2008, Jacksonville, Florida, USA / sponsored by Advanced Energy Systems Division, ASME; Solar Energy Division, ASME Y1 - 2009 SN - 9780791843208 N1 - International Conference on Energy Sustainability ; (2 : ; 2008.08.10-14 : ; Jacksonville, Fla.) ; ES ; (2 : ; 2008.08.10-14 : ; Jacksonville, Fla.) SP - 1 EP - 5 PB - ASME CY - New York, NY ER - TY - JOUR A1 - Göttsche, Joachim A1 - Schwarzer, Klemens A1 - Röther, S. A1 - Jellinghaus, Sabine T1 - Efficient daylighting, heating and shading with rooflight heliostats JF - Conference Internationale Energie Solaire et Batiment Y1 - 2009 SP - 243 EP - 248 PB - EPFL CY - Lausanne ER - TY - JOUR A1 - Göttsche, Joachim A1 - Hoffschmidt, Bernhard A1 - Schmitz, Stefan A1 - Sauerborn, Markus T1 - Solar Concentrating Systems Using Small Mirror Arrays JF - Journal of solar energy engineering Y1 - 2010 SN - 0199-6231 VL - Vol. 132 IS - Iss. 1 SP - 4 S. ER - TY - JOUR A1 - Schwarzer, Klemens A1 - Vieira da Silva, Maria Eugenia A1 - Schwarzer, Tarik T1 - Field results in Namibia and Brazil of the new solar desalination system for decentralised drinking water production JF - Desalination and water treatment. Vol. 31 (2011), iss. 1-3: selected papers presented at EuroMed 2010 — Desalination for Clean Water and Energy: Cooperation among Mediterranean Countries of Europe and MENA Region, 3–7 October 2010, Tel Aviv, Israel Y1 - 2011 SP - 379 EP - 386 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 - Reisgen, Uwe A1 - Schleser, Markus A1 - Abdurakhmanov, Aydemir A1 - Turichin, Gleb A1 - Valdaitseva, Elena A1 - Bach, Friedrich-Wilhelm A1 - Hassel, Thomas A1 - Beniyashi, Alexander T1 - Investigation of factors influencing the formation of weld defects in non-vacuum electron beam welding JF - The Paton welding journal N2 - 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. Y1 - 2012 SN - 0957-798X VL - 2012 IS - 2 SP - 11 EP - 18 PB - Paton Publishing House CY - Kiev ER - TY - JOUR A1 - Vieira da Silva, Maria Eugenia A1 - Schwarzer, Klemens A1 - Hoffschmidt, Bernhard A1 - Pinheiro Rodrigues, Frederico A1 - Schwarzer, Tarik A1 - Costa Rocha, Paulo Alexandre T1 - Mass transfer correlation for evaporation–condensation thermal process in the range of 70 °C–95 °C JF - Renewable energy Y1 - 2013 SN - 1879-0682 (E-Journal); 0960-1481 (Print) VL - Vol. 53 SP - 174 EP - 179 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Kronhardt, Valentina A1 - Alexopoulos, Spiros A1 - Reißel, Martin A1 - Sattler, Johannes, Christoph A1 - Hoffschmidt, Bernhard A1 - Hänel, Matthias A1 - Doerbeck, Till T1 - High-temperature thermal storage system for solar tower power plants with open-volumetric air receiver simulation and energy balancing of a discretized model JF - Energy procedia N2 - 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. Y1 - 2014 U6 - http://dx.doi.org/10.1016/j.egypro.2014.03.094 SN - 1876-6102 (E-Journal) ; 1876-6102 (Print) VL - 49 SP - 870 EP - 877 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Rau, Christoph A1 - Alexopoulos, Spiros A1 - Breitbach, Gerd A1 - Hoffschmidt, Bernhard A1 - Latzke, Markus A1 - Sattler, Johannes, Christoph T1 - Transient simulation of a solar-hybrid tower power plant with open volumetric receiver at the location Barstow JF - Energy procedia : proceedings of the SolarPACES 2013 International Conference N2 - 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. Y1 - 2014 U6 - http://dx.doi.org/10.1016/j.egypro.2014.03.157 SN - 1876-6102 VL - 49 SP - 1481 EP - 1490 PB - Elsevier CY - Amsterdam 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 - http://dx.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 -