TY - JOUR A1 - Edip, K. A1 - Sesov, V. A1 - Butenweg, Christoph A1 - Bojadjieva, J. T1 - Development of coupled numerical model for simulation of multiphase soil JF - Computers and Geotechnics N2 - In this paper, a coupled multiphase model considering both non-linearities of water retention curves and solid state modeling is proposed. The solid displacements and the pressures of both water and air phases are unknowns of the proposed model. The finite element method is used to solve the governing differential equations. The proposed method is demonstrated through simulation of seepage test and partially consolidation problem. Then, implementation of the model is done by using hypoplasticity for the solid phase and analyzing the fully saturated triaxial experiments. In integration of the constitutive law error controlling is improved and comparisons done accordingly. In this work, the advantages and limitations of the numerical model are discussed. Y1 - 2018 U6 - https://doi.org/10.1016/j.compgeo.2017.08.016 SN - 0266-352X VL - 96 SP - 118 EP - 131 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Rupp, Matthias A1 - Rieke, Christian A1 - Handschuh, Nils A1 - Kuperjans, Isabel T1 - Economic and ecological optimization of electric bus charging considering variable electricity prices and CO₂eq intensities JF - Transportation Research Part D: Transport and Environment N2 - In many cities, diesel buses are being replaced by electric buses with the aim of reducing local emissions and thus improving air quality. The protection of the environment and the health of the population is the highest priority of our society. For the transport companies that operate these buses, not only ecological issues but also economic issues are of great importance. Due to the high purchase costs of electric buses compared to conventional buses, operators are forced to use electric vehicles in a targeted manner in order to ensure amortization over the service life of the vehicles. A compromise between ecology and economy must be found in order to both protect the environment and ensure economical operation of the buses. In this study, we present a new methodology for optimizing the vehicles’ charging time as a function of the parameters CO₂eq emissions and electricity costs. Based on recorded driving profiles in daily bus operation, the energy demands of conventional and electric buses are calculated for the passenger transportation in the city of Aachen in 2017. Different charging scenarios are defined to analyze the influence of the temporal variability of CO₂eq intensity and electricity price on the environmental impact and economy of the bus. For every individual day of a year, charging periods with the lowest and highest costs and emissions are identified and recommendations for daily bus operation are made. To enable both the ecological and economical operation of the bus, the parameters of electricity price and CO₂ are weighted differently, and several charging periods are proposed, taking into account the priorities previously set. A sensitivity analysis is carried out to evaluate the influence of selected parameters and to derive recommendations for improving the ecological and economic balance of the battery-powered electric vehicle. In all scenarios, the optimization of the charging period results in energy cost savings of a maximum of 13.6% compared to charging at a fixed electricity price. The savings potential of CO₂eq emissions is similar, at 14.9%. From an economic point of view, charging between 2 a.m. and 4 a.m. results in the lowest energy costs on average. The CO₂eq intensity is also low in this period, but midday charging leads to the largest savings in CO₂eq emissions. From a life cycle perspective, the electric bus is not economically competitive with the conventional bus. However, from an ecological point of view, the electric bus saves on average 37.5% CO₂eq emissions over its service life compared to the diesel bus. The reduction potential is maximized if the electric vehicle exclusively consumes electricity from solar and wind power. Y1 - 2020 U6 - https://doi.org/10.1016/j.trd.2020.102293 SN - 1361-9209 VL - 81 IS - Article 102293 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Herrmann, Ulf A1 - Schwarzenbart, Marc A1 - Dittmann-Gabriel, Sören T1 - Speicher statt Kohle. Integration thermischer Stromspeicher in vorhandene Kraftwerksstandorte JF - BWK : Das Energie-Fachmagazin Y1 - 2019 SN - 1436-4883 VL - 71 IS - 4 SP - 42 EP - 45 PB - Springer-VDI-Verl. CY - Düsseldorf ER - TY - JOUR A1 - Birkl, Josef A1 - Diendorfer, Gerhard A1 - Kern, Alexander A1 - Thern, Stephan T1 - Extrem hohe Blitzströme JF - Elektropraktiker N2 - Blitze sind nach wie vor eine enorme Schadensquelle für Personenschäden, Brände, mechanische Zerstörungen und insbesondere auch Überspannungen. Das zeigen nicht zuletzt aktuelle Statistiken der Schadensversicherer. Immer wieder gibt es Meldungen über extrem hohe Blitzströme, die natürlich auch zu großen Schäden und Zerstörungen führen können. Dabei werden Scheitelwerte von teilweise deutlich über 300 kA genannt. Dies wirft Fragen auf, da die „klassische“ Blitzstatistik (z. B. nach CIGRE und IEC [8][10]) bisher solche Werte nicht kennt. Diese extremen Blitzströme werden meist aus den Daten von Blitzortungssystemen ermittelt. Y1 - 2018 VL - 72 IS - 3 SP - 217 EP - 225 PB - Huss Medien CY - Berlin ER - TY - JOUR A1 - Reger, Vitali A1 - Kuhnhenne, Markus A1 - Hachul, Helmut A1 - Döring, Bernd A1 - Blanke, Tobias A1 - Göttsche, Joachim T1 - Plusenergiegebäude 2.0 in Stahlleichtbauweise JF - Stahlbau Y1 - 2019 U6 - https://doi.org/10.1002/stab.201900034 SN - 1437-1049 (E-journal), 0038-9145 (print) VL - 88 IS - 6 SP - 522 EP - 528 PB - Ernst & Sohn CY - Berlin ER - TY - JOUR A1 - Dotzauer, Martin A1 - Pfeiffer, Diana A1 - Lauer, Markus A1 - Pohl, Marcel A1 - Mauky, Eric A1 - Bär, Katharina A1 - Sonnleitner, Matthias A1 - Zörner, Wilfried A1 - Hudde, Jessica A1 - Schwarz, Björn A1 - Faßauer, Burkhardt A1 - Dahmen, Markus A1 - Rieke, Christian A1 - Herbert, Johannes A1 - Thrän, Daniela T1 - How to measure flexibility – Performance indicators for demand driven power generation from biogas plants JF - Renewable Energy Y1 - 2019 U6 - https://doi.org/10.1016/j.renene.2018.10.021 SN - 0960-1481 SP - 135 EP - 146 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Rupp, Matthias A1 - Handschuh, Nils A1 - Rieke, Christian A1 - Kuperjans, Isabel T1 - Contribution of country-specific electricity mix and charging time to environmental impact of battery electric vehicles: A case study of electric buses in Germany JF - Applied Energy Y1 - 2019 U6 - https://doi.org/10.1016/j.apenergy.2019.01.059 SN - 0306-2619 VL - 237 SP - 618 EP - 634 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Rieke, Christian A1 - Stollenwerk, Dominik A1 - Dahmen, Markus A1 - Pieper, Martin T1 - Modeling and optimization of a biogas plant for a demand-driven energy supply JF - Energy N2 - Due to the Renewable Energy Act, in Germany it is planned to increase the amount of renewable energy carriers up to 60%. One of the main problems is the fluctuating supply of wind and solar energy. Here biogas plants provide a solution, because a demand-driven supply is possible. Before running such a plant, it is necessary to simulate and optimize the process. This paper provides a new model of a biogas plant, which is as accurate as the standard ADM1 model. The advantage compared to ADM1 is that it is based on only four parameters compared to 28. Applying this model, an optimization was installed, which allows a demand-driven supply by biogas plants. Finally the results are confirmed by several experiments and measurements with a real test plant. Y1 - 2018 U6 - https://doi.org/10.1016/j.energy.2017.12.073 SN - 0360-5442 VL - 145 SP - 657 EP - 664 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Srivastava, A. A1 - Chahar, V. A1 - Sharma, V. A1 - Sun, Y. A1 - Bol, R. A1 - Knolle, F. A1 - Schnug, E. A1 - Hoyler, Friedrich A1 - Naskar, N. A1 - Lahiri, S. A1 - Patnaik, R. T1 - Study of uranium toxicity using low-background gamma-ray spectrometry JF - Journal of Radioanalytical and Nuclear Chemistry Y1 - 2017 U6 - https://doi.org/10.1007/s10967-017-5466-9 SN - 1588-2780 IS - Online first SP - 1 EP - 7 PB - Springer CY - Berlin ER - TY - JOUR A1 - Alexopoulos, Spiros A1 - Hoffschmidt, Bernhard T1 - Advances in solar tower technology JF - Wiley interdisciplinary reviews : Energy and Environment : WIREs Y1 - 2017 U6 - https://doi.org/10.1002/wene.217 SN - 2041-840X VL - 6 IS - 1 SP - 1 EP - 19 PB - Wiley CY - Weinheim ER -