TY - CHAP A1 - Sattler, Johannes, Christoph A1 - Caminos, Ricardo Alexander Chico A1 - Ürlings, Nicolas A1 - Dutta, Siddharth A1 - Ruiz, Victor A1 - Kalogirou, Soteris A1 - Ktistis, Panayiotis A1 - Agathokleous, Rafaela A1 - Jung, Christian A1 - Alexopoulos, Spiros A1 - Atti, Vikrama Nagababu A1 - Teixeira Boura, Cristiano José A1 - Herrmann, Ulf T1 - Operational experience and behaviour of a parabolic trough collector system with concrete thermal energy storage for process steam generation in Cyprus T2 - AIP Conference Proceedings N2 - 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 Ingeniería, 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. Y1 - 2020 U6 - https://doi.org/10.1063/5.0029278 N1 - SOLARPACES 2019: International Conference on Concentrating Solar Power and Chemical Energy Systems, 1–4 October 2019, Daegu, South Korea IS - 2303 SP - 140004-1 EP - 140004-10 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 - CHAP A1 - Frantz, Cathy A1 - Binder, Matthias A1 - Busch, Konrad A1 - Ebert, Miriam A1 - Heinrich, Andreas A1 - Kaczmarkiewicz, Nadine A1 - Schlögl-Knothe, Bärbel A1 - Kunze, Tobias A1 - Schuhbauer, Christian A1 - Stetka, Markus A1 - Schwager, Christian A1 - Spiegel, Michael A1 - Teixeira Boura, Cristiano José A1 - Bauer, Thomas A1 - Bonk, Alexander A1 - Eisen, Stefan A1 - Funck, Bernhard T1 - Basic Engineering of a High Performance Molten Salt Tower Receiver System T2 - AIP Conference Proceedings N2 - The production of dispatchable renewable energy will be one of the most important key factors of the future energy supply. Concentrated solar power (CSP) plants operated with molten salt as heat transfer and storage media are one opportunity to meet this challenge. Due to the high concentration factor of the solar tower technology the maximum process temperature can be further increased which ultimately decreases the levelized costs of electricity of the technology (LCOE). The development of an improved tubular molten salt receiver for the next generation of molten salt solar tower plants is the aim of this work. The receiver is designed for a receiver outlet temperature up to 600 °C. Together with a complete molten salt system, the receiver will be integrated into the Multi-Focus-Tower (MFT) in Jülich (Germany). The paper describes the basic engineering of the receiver, the molten salt tower system and a laboratory corrosion setup. Y1 - 2020 U6 - https://doi.org/10.1063/5.0085895 N1 - SOLARPACES 2020: 26th International Conference on Concentrating Solar Power and Chemical Energy Systems, 28 September – 2 October 2020, Freiburg, Germany SP - 1 EP - 10 ER - TY - JOUR A1 - El Moussaoui, Noureddine A1 - Talbi, Sofian A1 - Atmane, Ilyas A1 - Kassmi, Khalil A1 - Schwarzer, Klemens A1 - Chayeb, Hamid A1 - Bachiri, Najib T1 - Feasibility of a new design of a Parabolic Trough Solar Thermal Cooker (PSTC) JF - Solar Energy N2 - In this article, we describe the structure, the functioning, and the tests of parabolic trough solar thermal cooker (PSTC). This oven is designed to meet the needs of rural residents, including Urban, which requires stable cooking temperatures above 200 °C. The cooking by this cooker is based on the concentration of the sun's rays on a glass vacuum tube and heating of the oil circulate in a big tube, located inside the glass tube. Through two small tubes, associated with large tube, the heated oil, rise and heats the pot of cooking pot containing the food to be cooked (capacity of 5 kg). This cooker is designed in Germany and extensively tested in Morocco for use by the inhabitants who use wood from forests. During a sunny day, having a maximum solar radiation around 720 W/m2 and temperature ambient around 26 °C, maximum temperatures recorded of the small tube, the large tube and the center of the pot are respectively: 370 °C, 270 °C and 260 °C. The cooking process with food at high (fries, ..), we show that the cooking oil temperature rises to 200 °C, after 1 h of heating, the cooking is done at a temperature of 120 °C for 20 min. These temperatures are practically stable following variations and decreases in the intensity of irradiance during the day. The comparison of these results with those of the literature shows an improvement of 30–50 % on the maximum value of the temperature with a heat storage that could reach 60 min of autonomy. All the results obtained show the good functioning of the PSTC and the feasibility of cooking food at high temperature (>200 °C). Y1 - 2020 U6 - https://doi.org/10.1016/j.solener.2020.03.079 SN - 0038-092X VL - 201 IS - Vol. 201 (May 2020) SP - 866 EP - 871 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Sattler, Johannes, Christoph A1 - Röger, Marc A1 - Schwarzbözl, Peter A1 - Buck, Reiner A1 - Macke, Ansgar A1 - Raeder, Christian A1 - Göttsche, Joachim T1 - Review of heliostat calibration and tracking control methods JF - Solar Energy N2 - Large scale central receiver systems typically deploy between thousands to more than a hundred thousand heliostats. During solar operation, each heliostat is aligned individually in such a way that the overall surface normal bisects the angle between the sun’s position and the aim point coordinate on the receiver. Due to various tracking error sources, achieving accurate alignment ≤1 mrad for all the heliostats with respect to the aim points on the receiver without a calibration system can be regarded as unrealistic. Therefore, a calibration system is necessary not only to improve the aiming accuracy for achieving desired flux distributions but also to reduce or eliminate spillage. An overview of current larger-scale central receiver systems (CRS), tracking error sources and the basic requirements of an ideal calibration system is presented. Leading up to the main topic, a description of general and specific terms on the topics heliostat calibration and tracking control clarifies the terminology used in this work. Various figures illustrate the signal flows along various typical components as well as the corresponding monitoring or measuring devices that indicate or measure along the signal (or effect) chain. The numerous calibration systems are described in detail and classified in groups. Two tables allow the juxtaposition of the calibration methods for a better comparison. In an assessment, the advantages and disadvantages of individual calibration methods are presented. Y1 - 2020 U6 - https://doi.org/10.1016/j.solener.2020.06.030 VL - 207 SP - 110 EP - 132 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Kreyer, Jörg A1 - Müller, Marvin A1 - Esch, Thomas T1 - A Map-Based Model for the Determination of Fuel Consumption for Internal Combustion Engines as a Function of Flight Altitude N2 - In addition to very high safety and reliability requirements, the design of internal combustion engines (ICE) in aviation focuses on economic efficiency. The objective must be to design the aircraft powertrain optimized for a specific flight mission with respect to fuel consumption and specific engine power. Against this background, expert tools provide valuable decision-making assistance for the customer. In this paper, a mathematical calculation model for the fuel consumption of aircraft ICE is presented. This model enables the derivation of fuel consumption maps for different engine configurations. Depending on the flight conditions and based on these maps, the current and the integrated fuel consumption for freely definable flight emissions is calculated. For that purpose, an interpolation method is used, that has been optimized for accuracy and calculation time. The mission boundary conditions flight altitude and power requirement of the ICE form the basis for this calculation. The mathematical fuel consumption model is embedded in a parent program. This parent program presents the simulated fuel consumption by means of an example flight mission for a representative airplane. The focus of the work is therefore on reproducing exact consumption data for flight operations. By use of the empirical approaches according to Gagg-Farrar [1] the power and fuel consumption as a function of the flight altitude are determined. To substantiate this approaches, a 1-D ICE model based on the multi-physical simulation tool GT-Suite® has been created. This 1-D engine model offers the possibility to analyze the filling and gas change processes, the internal combustion as well as heat and friction losses for an ICE under altitude environmental conditions. Performance measurements on a dynamometer at sea level for a naturally aspirated ICE with a displacement of 1211 ccm used in an aviation aircraft has been done to validate the 1-D ICE model. To check the plausibility of the empirical approaches with respect to the fuel consumption and performance adjustment for the flight altitude an analysis of the ICE efficiency chain of the 1-D engine model is done. In addition, a comparison of literature and manufacturer data with the simulation results is presented. Y1 - 2020 U6 - https://doi.org/10.25967/490162 N1 - 68. Deutscher Luft- und Raumfahrtkongress 30.09.-02.10.2019, Darmstadt PB - DGLR CY - Bonn ER - TY - CHAP A1 - Sattler, Johannes, Christoph A1 - Alexopoulos, Spiros A1 - Caminos, Ricardo Alexander Chico A1 - Mitchell, John C. A1 - Ruiz, Victor C. A1 - Kalogirou, Soteris A1 - Ktistis, Panayiotis K. A1 - Teixeira Boura, Cristiano José A1 - Herrmann, Ulf T1 - Dynamic simulation model of a parabolic trough collector system with concrete thermal energy storage for process steam generation T2 - AIP Conference Proceedings Y1 - 2019 U6 - https://doi.org/10.1063/1.5117663 SN - 0094243X VL - 2126 SP - 150007-1 EP - 150007-8 ER - TY - CHAP A1 - May, Martin A1 - Breitbach, Gerd A1 - Alexopoulos, Spiros A1 - Latzke, Markus A1 - Bäumer, Klaus A1 - Uhlig, Ralf A1 - Söhn, Matthias A1 - Teixeira Boura, Cristiano José A1 - Herrmann, Ulf T1 - Experimental facility for investigations of wire mesh absorbers for pressurized gases T2 - AIP Conference Proceedings Y1 - 2019 U6 - https://doi.org/10.1063/1.5117547 SN - 0094243X VL - 2126 SP - 030035-1 EP - 030035-9 ER - TY - CHAP A1 - Mahdi, Zahra A1 - Rendón, Carlos A1 - Schwager, Christian A1 - Teixeira Boura, Cristiano José A1 - Herrmann, Ulf T1 - Novel concept for indirect solar-heated methane reforming T2 - AIP Conference Proceedings Y1 - 2019 U6 - https://doi.org/10.1063/1.5117694 SN - 0094-243X VL - 2126 SP - 180014-1 EP - 180014-7 PB - AIP Publishing CY - Melville, NY ER - TY - CHAP A1 - Breitbach, Gerd A1 - Alexopoulos, Spiros A1 - May, Martin A1 - Teixeira Boura, Cristiano José A1 - Herrmann, Ulf T1 - Analysis of volumetric solar radiation absorbers made of wire meshes T2 - AIP Conference Proceedings Y1 - 2019 U6 - https://doi.org/10.1063/1.5117521 SN - 0094243X VL - 2126 SP - 030009-1 EP - 030009-6 ER - TY - CHAP A1 - Blanke, Tobias A1 - Dring, Bernd A1 - Vontein, Marius A1 - Kuhnhenne, Markus T1 - Climate Change Mitigation Potentials of Vertical Building Integrated Photovoltaic T2 - 8th International Workshop on Integration of Solar Power into Power Systems : 16-17 October 2018, Stockholm, Sweden Y1 - 2018 SP - 1 EP - 7 ER - TY - JOUR A1 - Wolisz, Henryk A1 - Schütz, Thomas A1 - Blanke, Tobias A1 - Hagenkamp, Markus A1 - Kohrn, Markus A1 - Wesseling, Mark A1 - Müller, Dirk T1 - Cost optimal sizing of smart buildings' energy system components considering changing end-consumer electricity markets JF - Energy Y1 - 2017 U6 - https://doi.org/10.1016/j.energy.2017.06.025 VL - 137 SP - 715 EP - 728 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Schwager, Christian A1 - Teixeira Boura, Cristiano José A1 - Flesch, Robert A1 - Alexopoulos, Spiros A1 - Herrmann, Ulf T1 - Improved efficiency prediction of a molten salt receiver based on dynamic cloud passage simulation T2 - AIP Conference Proceedings Y1 - 2019 SN - 978-0-7354-1866-0 U6 - https://doi.org/10.1063/1.5117566 VL - 2126 IS - 1 SP - 030054-1 EP - 030054-8 ER - TY - CHAP A1 - Gorzalka, Philip A1 - Dahlke, Dennis A1 - Göttsche, Joachim A1 - Israel, Martin A1 - Patel, Dhruvkumar A1 - Prahl, Christoph A1 - Schmiedt, Jacob Estevam A1 - Frommholz, Dirk A1 - Hoffschmidt, Bernhard A1 - Linkiewicz, Magdalena T1 - Building Tomograph–From Remote Sensing Data of Existing Buildings to Building Energy Simulation Input T2 - EBC, Annex 71, Fifth expert meeting, October 17-19, 2018, Innsbruck, Austria Y1 - 2018 ER - TY - JOUR A1 - Puppe, Michael A1 - Giuliano, Stefano A1 - Frantz, Cathy A1 - Uhlig, Ralf A1 - Schumacher, Ralph A1 - Ibraheem, Wagdi A1 - Schmalz, Stefan A1 - Waldmann, Barbara A1 - Guder, Christoph A1 - Peter, Dennis A1 - Schwager, Christian A1 - Teixeira Boura, Cristiano José A1 - Alexopoulos, Spiros A1 - Spiegel, Michael A1 - Wortmann, Jürgen A1 - Hinrichs, Matthias A1 - Engelhard, Manfred A1 - Aust, Michael T1 - Techno-economic optimization of molten salt solar tower plants JF - AIP Conference Proceedings art.no. 040033 N2 - In this paper the results of a techno-economic analysis of improved and optimized molten salt solar tower plants (MSSTP plants) are presented. The potential improvements that were analyzed include different receiver designs, different designs of the HTF-system and plant control, increased molten salt temperatures (up to 640°C) and multi-tower systems. Detailed technological and economic models of the solar field, solar receiver and high temperature fluid system (HTF-system) were developed and used to find potential improvements compared to a reference plant based on Solar Two technology and up-to-date cost estimations. The annual yield model calculates the annual outputs and the LCOE of all variants. An improved external tubular receiver and improved HTF-system achieves a significant decrease of LCOE compared to the reference. This is caused by lower receiver cost as well as improvements of the HTF-system and plant operation strategy, significantly reducing the plant own consumption. A novel star receiver shows potential for further cost decrease. The cavity receiver concepts result in higher LCOE due to their high investment cost, despite achieving higher efficiencies. Increased molten salt temperatures seem possible with an adapted, closed loop HTF-system and achieve comparable results to the original improved system (with 565°C) under the given boundary conditions. In this analysis all multi tower systems show lower economic viability compared to single tower systems, caused by high additional cost for piping connections and higher cost of the receivers. REFERENCES Y1 - 2019 U6 - https://doi.org/10.1063/1.5067069 VL - 2033 IS - Issue 1 PB - AIP Publishing CY - Melville, NY ER - TY - CHAP A1 - Rendon, Carlos A1 - Dieckmann, Simon A1 - Weidle, Mathias A1 - Dersch, Jürgen A1 - Teixeira Boura, Cristiano José A1 - Polklas, Thomas A1 - Kuschel, Marcus A1 - Herrmann, Ulf T1 - Retrofitting of existing parabolic trough collector power plants with molten salt tower systems T2 - AIP Conference Proceedings Y1 - 2018 U6 - https://doi.org/10.1063/1.5067030 VL - 2033 IS - 1 SP - 030014-1 EP - 030014-8 ER - TY - CHAP A1 - Herrmann, Ulf A1 - Kearney, D. A1 - Röger, M. A1 - Prahl, C. T1 - System performance measurements T2 - The Performance of Concentrated Solar Power (CSP) Systems : Modelling, Measurement and Assessment N2 - This chapter introduces performance and acceptance testing and describes state-of-the-art tools, methods, and instruments to assess the plant performance or realize plant acceptance testing. The status of the development of standards for performance assessment is given. KW - Performance measurement KW - Acceptance tests KW - Plant efficiency Y1 - 2017 SN - 978-0-08-100448-7 U6 - https://doi.org/https://doi.org/10.1016/B978-0-08-100447-0.00005-5 SP - 115 EP - 165 PB - Woodhead Publishing CY - Duxford ER - TY - CHAP A1 - Sauerborn, Markus A1 - Liebenstund, Lena A1 - Raue, Markus A1 - Mang, Thomas A1 - Herrmann, Ulf A1 - Dueing, Andreas T1 - Analytic method for material aging and quality analyzing to forecast long time stability of plastic micro heliostat components T2 - AIP Conference Proceedings Y1 - 2017 U6 - https://doi.org/10.1063/1.4984388 VL - 1850 IS - 1 SP - 030045-1 EP - 030045-8 ER - TY - CHAP A1 - Teixeira Boura, Cristiano José A1 - Niederwestberg, Stefan A1 - McLeod, Jacqueline A1 - Herrmann, Ulf A1 - Hoffschmidt, Bernhard T1 - Development of heat exchanger for high temperature energy storage with bulk materials T2 - AIP Conference Proceedings Y1 - 2016 U6 - https://doi.org/10.1063/1.4949106 VL - 1734 IS - 1 SP - 050008-1 EP - 050008-7 ER - TY - CHAP A1 - Anthrakidis, Anette A1 - Herrmann, Ulf A1 - Schorn, Christian A1 - Schwarzer, Klemens A1 - Wedding, Philipp A1 - Weis, Fabian T1 - Development and Testing of a Novel Method for the Determination of the Efficiency of Concentrating Solar Thermal Collectors T2 - Conference Proceedings Solar World Congress 2015, Daegu, Korea, 08 – 12 November 2015 Y1 - 2015 ER -