@inproceedings{SchulzeBuxlohGrossUlbrich2021, author = {Schulze-Buxloh, Lina and Groß, Rolf Fritz and Ulbrich, Michelle}, title = {Digital planning using building information modelling and virtual reality: new approach for students' remote practical training under lockdown conditions in the course of smart building engineering}, series = {Proceedings of International Conference on Education in Mathematics, Science and Technology 2021}, booktitle = {Proceedings of International Conference on Education in Mathematics, Science and Technology 2021}, publisher = {ISTES Organization}, address = {San Antonio, TX}, isbn = {978-1-952092-17-6}, pages = {118 -- 123}, year = {2021}, abstract = {The worldwide Corona pandemic has severely restricted student projects in the higher semesters of engineering courses. In order not to delay the graduation, a new concept had to be developed for projects under lockdown conditions. Therefore, unused rooms at the university should be digitally recorded in order to develop a new usage concept as laboratory rooms. An inventory of the actual state of the rooms was done first by taking photos and listing up all flaws and peculiarities. After that, a digital site measuring was done with a 360° laser scanner and these recorded scans were linked to a coherent point cloud and transferred to a software for planning technical building services and supporting Building Information Modelling (BIM). In order to better illustrate the difference between the actual and target state, two virtual reality models were created for realistic demonstration. During the project, the students had to go through the entire digital planning phases. Technical specifications had to be complied with, as well as documentation, time planning and cost estimate. This project turned out to be an excellent alternative to on-site practical training under lockdown conditions and increased the students' motivation to deal with complex technical questions.}, language = {en} } @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, N.}, 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} } @inproceedings{AlexopoulosBreitbachHoffschmidt2009, author = {Alexopoulos, Spiros and Breitbach, Gerd and Hoffschmidt, Bernhard}, title = {Optimization of the channel form geometry of porous ReSiC ceramic membrane modules}, series = {Proceedings / International Conference \& Exhibition for Filtration and Separation Technology, FILTECH 2009 : October 13 - 15, 2009, Wiesbaden, Germany. Vol. 2}, booktitle = {Proceedings / International Conference \& Exhibition for Filtration and Separation Technology, FILTECH 2009 : October 13 - 15, 2009, Wiesbaden, Germany. Vol. 2}, publisher = {Filtech Exhibitions Germany}, address = {Meerbusch}, isbn = {978-3-941655-36-2}, pages = {686 -- 693}, year = {2009}, language = {en} } @inproceedings{AhlbrinkAlexopoulosAnderssonetal.2009, author = {Ahlbrink, N. and Alexopoulos, Spiros and Andersson, J. and Belhomme, B. and Teixeira Boura, Cristiano Jos{\´e} and Gall, J. and Hirsch, T.}, title = {viCERP - the Virtual Institute of Central Receiver Power Plant}, series = {MATHMOD 2009 - 6th Vienna International Conference on Mathematical Modelling : February 11 - 13, 2009, Vienna, Austria. ARGESIM Report. No. 35}, booktitle = {MATHMOD 2009 - 6th Vienna International Conference on Mathematical Modelling : February 11 - 13, 2009, Vienna, Austria. ARGESIM Report. No. 35}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {978-3-901608-35-3}, year = {2009}, language = {en} } @article{AlexopoulosHoffschmidt2017, author = {Alexopoulos, Spiros and Hoffschmidt, Bernhard}, title = {Advances in solar tower technology}, series = {Wiley interdisciplinary reviews : Energy and Environment : WIREs}, volume = {6}, journal = {Wiley interdisciplinary reviews : Energy and Environment : WIREs}, number = {1}, publisher = {Wiley}, address = {Weinheim}, issn = {2041-840X}, doi = {10.1002/wene.217}, pages = {1 -- 19}, year = {2017}, language = {en} } @article{Alexopoulos2015, author = {Alexopoulos, Spiros}, title = {Simulation model for the transient process behaviour of solar aluminium recycling in a rotary kiln}, series = {Applied Thermal Engineering}, volume = {78}, journal = {Applied Thermal Engineering}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1359-4311}, doi = {10.1016/j.applthermaleng.2015.01.007}, pages = {387 -- 396}, year = {2015}, 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{ElMoussaouiKassmiAlexopoulosetal.2021, author = {El Moussaoui, Noureddine and Kassmi, Khalil and Alexopoulos, Spiros and Schwarzer, Klemens and Chayeb, Hamid and Bachiri, Najib}, title = {Simulation studies on a new innovative design of a hybrid solar distiller MSDH alimented with a thermal and photovoltaic energy}, series = {Materialstoday: Proceedings}, volume = {45}, booktitle = {Materialstoday: Proceedings}, number = {8}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2214-7853}, doi = {10.1016/j.matpr.2021.03.115}, pages = {7653 -- 7660}, year = {2021}, abstract = {In this paper, we present the structure, the simulation the operation of a multi-stage, hybrid solar desalination system (MSDH), powered by thermal and photovoltaic (PV) (MSDH) energy. The MSDH system consists of a lower basin, eight horizontal stages, a field of four flat thermal collectors with a total area of 8.4 m2, 3 Kw PV panels and solar batteries. During the day the system is heated by thermal energy, and at night by heating resistors, powered by solar batteries. These batteries are charged by the photovoltaic panels during the day. More specifically, during the day and at night, we analyse the temperature of the stages and the production of distilled water according to the solar irradiation intensity and the electric heating power, supplied by the solar batteries. The simulations were carried out in the meteorological conditions of the winter month (February 2020), presenting intensities of irradiance and ambient temperature reaching 824 W/m2 and 23 °C respectively. The results obtained show that during the day the system is heated by the thermal collectors, the temperature of the stages and the quantity of water produced reach 80 °C and 30 Kg respectively. At night, from 6p.m. the system is heated by the electric energy stored in the batteries, the temperature of the stages and the quantity of water produced reach respectively 90 °C and 104 Kg for an electric heating power of 2 Kw. Moreover, when the electric power varies from 1 Kw to 3 Kw the quantity of water produced varies from 92 Kg to 134 Kg. The analysis of these results and their comparison with conventional solar thermal desalination systems shows a clear improvement both in the heating of the stages, by 10\%, and in the quantity of water produced by a factor of 3.}, 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{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} }