@article{CheenakulaHoffstadtKrafftetal.2022, author = {Cheenakula, Dheeraja and Hoffstadt, Kevin and Krafft, Simone and Reinecke, Diana and Klose, Holger and Kuperjans, Isabel and Gr{\"o}mping, Markus}, title = {Anaerobic digestion of algal-bacterial biomass of an Algal Turf Scrubber system}, series = {Biomass Conversion and Biorefinery}, volume = {13}, journal = {Biomass Conversion and Biorefinery}, publisher = {Springer}, address = {Berlin}, issn = {2190-6823}, doi = {10.1007/s13399-022-03236-z}, pages = {15 Seiten}, year = {2022}, abstract = {This study investigated the anaerobic digestion of an algal-bacterial biofilm grown in artificial wastewater in an Algal Turf Scrubber (ATS). The ATS system was located in a greenhouse (50°54′19ʺN, 6°24′55ʺE, Germany) and was exposed to seasonal conditions during the experiment period. The methane (CH4) potential of untreated algal-bacterial biofilm (UAB) and thermally pretreated biofilm (PAB) using different microbial inocula was determined by anaerobic batch fermentation. Methane productivity of UAB differed significantly between microbial inocula of digested wastepaper, a mixture of manure and maize silage, anaerobic sewage sludge, and percolated green waste. UAB using sewage sludge as inoculum showed the highest methane productivity. The share of methane in biogas was dependent on inoculum. Using PAB, a strong positive impact on methane productivity was identified for the digested wastepaper (116.4\%) and a mixture of manure and maize silage (107.4\%) inocula. By contrast, the methane yield was significantly reduced for the digested anaerobic sewage sludge (50.6\%) and percolated green waste (43.5\%) inocula. To further evaluate the potential of algal-bacterial biofilm for biogas production in wastewater treatment and biogas plants in a circular bioeconomy, scale-up calculations were conducted. It was found that a 0.116 km2 ATS would be required in an average municipal wastewater treatment plant which can be viewed as problematic in terms of space consumption. However, a substantial amount of energy surplus (4.7-12.5 MWh a-1) can be gained through the addition of algal-bacterial biomass to the anaerobic digester of a municipal wastewater treatment plant. Wastewater treatment and subsequent energy production through algae show dominancy over conventional technologies.}, language = {en} } @article{KuperjansStarkeEsseretal.2000, author = {Kuperjans, Isabel and Starke, M. and Esser, J. and [u.a.],}, title = {Analyse und Konzeption von Energieanlagen unter {\"o}kologischen, wirtschaftlichen und technischen Gesichtspunkten}, series = {WLB : Umwelttechnik f{\"u}r Industrie und Kommune}, volume = {44}, journal = {WLB : Umwelttechnik f{\"u}r Industrie und Kommune}, number = {11/12}, issn = {0341-2679}, pages = {26 -- 29}, year = {2000}, language = {de} } @article{BlockViebahnJungbluth2024, author = {Block, Simon and Viebahn, Peter and Jungbluth, Christian}, title = {Analysing direct air capture for enabling negative emissions in Germany: an assessment of the resource requirements and costs of a potential rollout in 2045}, series = {Frontiers in Climate}, volume = {6}, journal = {Frontiers in Climate}, publisher = {Frontiers}, address = {Lausanne}, issn = {2624-9553}, doi = {10.3389/fclim.2024.1353939}, pages = {18 Seiten}, year = {2024}, abstract = {Direct air capture (DAC) combined with subsequent storage (DACCS) is discussed as one promising carbon dioxide removal option. The aim of this paper is to analyse and comparatively classify the resource consumption (land use, renewable energy and water) and costs of possible DAC implementation pathways for Germany. The paths are based on a selected, existing climate neutrality scenario that requires the removal of 20 Mt of carbon dioxide (CO2) per year by DACCS from 2045. The analysis focuses on the so-called "low-temperature" DAC process, which might be more advantageous for Germany than the "high-temperature" one. In four case studies, we examine potential sites in northern, central and southern Germany, thereby using the most suitable renewable energies for electricity and heat generation. We show that the deployment of DAC results in large-scale land use and high energy needs. The land use in the range of 167-353 km2 results mainly from the area required for renewable energy generation. The total electrical energy demand of 14.4 TWh per year, of which 46\% is needed to operate heat pumps to supply the heat demand of the DAC process, corresponds to around 1.4\% of Germany's envisaged electricity demand in 2045. 20 Mt of water are provided yearly, corresponding to 40\% of the city of Cologne's water demand (1.1 million inhabitants). The capture of CO2 (DAC) incurs levelised costs of 125-138 EUR per tonne of CO2, whereby the provision of the required energy via photovoltaics in southern Germany represents the lowest value of the four case studies. This does not include the costs associated with balancing its volatility. Taking into account transporting the CO2 via pipeline to the port of Wilhelmshaven, followed by transporting and sequestering the CO2 in geological storage sites in the Norwegian North Sea (DACCS), the levelised costs increase to 161-176 EUR/tCO2. Due to the longer transport distances from southern and central Germany, a northern German site using wind turbines would be the most favourable.}, language = {en} } @article{MaurerRiekeSchemmetal.2023, author = {Maurer, Florian and Rieke, Christian and Schemm, Ralf and Stollenwerk, Dominik}, title = {Analysis of an urban grid with high photovoltaic and e-mobility penetration}, series = {Energies}, volume = {16}, journal = {Energies}, number = {8}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {10.3390/en16083380}, pages = {18 Seiten}, year = {2023}, abstract = {This study analyses the expected utilization of an urban distribution grid under high penetration of photovoltaic and e-mobility with charging infrastructure on a residential level. The grid utilization and the corresponding power flow are evaluated, while varying the control strategies and photovoltaic installed capacity in different scenarios. Four scenarios are used to analyze the impact of e-mobility. The individual mobility demand is modelled based on the largest German studies on mobility "Mobilit{\"a}t in Deutschland", which is carried out every 5 years. To estimate the ramp-up of photovoltaic generation, a potential analysis of the roof surfaces in the supply area is carried out via an evaluation of an open solar potential study. The photovoltaic feed-in time series is derived individually for each installed system in a resolution of 15 min. The residential consumption is estimated using historical smart meter data, which are collected in London between 2012 and 2014. For a realistic charging demand, each residential household decides daily on the state of charge if their vehicle requires to be charged. The resulting charging time series depends on the underlying behavior scenario. Market prices and mobility demand are therefore used as scenario input parameters for a utility function based on the current state of charge to model individual behavior. The aggregated electricity demand is the starting point of the power flow calculation. The evaluation is carried out for an urban region with approximately 3100 residents. The analysis shows that increased penetration of photovoltaics combined with a flexible and adaptive charging strategy can maximize PV usage and reduce the need for congestion-related intervention by the grid operator by reducing the amount of kWh charged from the grid by 30\% which reduces the average price of a charged kWh by 35\% to 14 ct/kWh from 21.8 ct/kWh without PV optimization. The resulting grid congestions are managed by implementing an intelligent price or control signal. The analysis took place using data from a real German grid with 10 subgrids. The entire software can be adapted for the analysis of different distribution grids and is publicly available as an open-source software library on GitHub.}, language = {en} } @article{ButenwegRosinHoller2017, author = {Butenweg, Christoph and Rosin, Julia and Holler, Stefan}, title = {Analysis of cylindrical granular material silos under seismic excitation}, series = {Buildings}, volume = {7}, journal = {Buildings}, number = {3}, publisher = {MDPI}, address = {Basel}, issn = {2075-5309}, doi = {10.3390/buildings7030061}, pages = {1 -- 12}, year = {2017}, abstract = {Silos generally work as storage structures between supply and demand for various goods, and their structural safety has long been of interest to the civil engineering profession. This is especially true for dynamically loaded silos, e.g., in case of seismic excitation. Particularly thin-walled cylindrical silos are highly vulnerable to seismic induced pressures, which can cause critical buckling phenomena of the silo shell. The analysis of silos can be carried out in two different ways. In the first, the seismic loading is modeled through statically equivalent loads acting on the shell. Alternatively, a time history analysis might be carried out, in which nonlinear phenomena due to the filling as well as the interaction between the shell and the granular material are taken into account. The paper presents a comparison of these approaches. The model used for the nonlinear time history analysis considers the granular material by means of the intergranular strain approach for hypoplasticity theory. The interaction effects between the granular material and the shell is represented by contact elements. Additionally, soil-structure interaction effects are taken into account.}, language = {en} } @article{BarsovBechstedtHardt2001, author = {Barsov, S. and Bechstedt, U. and Hardt, Arno}, title = {ANKE, a new facility for medium energy hadron physics at COSY-J{\"u}lich / S. Barsov [u.a.]}, series = {Nuclear instruments and methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. Vol. 462, iss. 3}, journal = {Nuclear instruments and methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. Vol. 462, iss. 3}, issn = {0167-5087 (Print) ; 0168-9002 (E-journal)}, pages = {364 -- 381}, year = {2001}, language = {en} } @article{KernZischankBeierl2007, author = {Kern, Alexander and Zischank, Wolfgang and Beierl, Ottmar}, title = {Anmerkungen zur Berechnung des Trennungsabstands nach DIN EN 62305-3 (VDE 0185-305-3): 2006-10 / Zischank, Wolfgang ; Beierl, Ottmar ; Kern, Alexander}, series = {7. VDE-ABB-Blitzschutztagung : Vortr{\"a}ge der VDE-ABB-Fachtagung vom 15. bis 16. November 2007 in Neu-Ulm / Veranst.: Ausschuss f{\"u}r Blitzschutz und Blitzforschung (ABB) im VDE, Verband der Elektrotechnik, Elektronik, Informationstechnik e.V. Wiss. Tagungsltg.: K. Stimper}, journal = {7. VDE-ABB-Blitzschutztagung : Vortr{\"a}ge der VDE-ABB-Fachtagung vom 15. bis 16. November 2007 in Neu-Ulm / Veranst.: Ausschuss f{\"u}r Blitzschutz und Blitzforschung (ABB) im VDE, Verband der Elektrotechnik, Elektronik, Informationstechnik e.V. Wiss. Tagungsltg.: K. Stimper}, publisher = {VDE-Verl.}, address = {Berlin}, isbn = {978-3-8007-3062-9}, pages = {1 -- 8}, year = {2007}, language = {de} } @article{FoersterDarmoDubeckyetal.1996, author = {F{\"o}rster, Arnold and Darmo, J. and Dubeck{\´y}, F. and Kordos, P.}, title = {Annealing characteristics of native defects in low-temperature-grown MBE GaAs / J. Darmo ; F. Dubecky ; P. Kordos ; A. F{\"o}rster}, series = {Semiconducting and insulating materials 1996 : proceedings of the 9th Conference on Semiconducting and Insulating Materials (SIMC '9), April 29 - May 3, 1996, Toulouse, France / [IEEE]}, journal = {Semiconducting and insulating materials 1996 : proceedings of the 9th Conference on Semiconducting and Insulating Materials (SIMC '9), April 29 - May 3, 1996, Toulouse, France / [IEEE]}, address = {Piscataway, NJ [u.a.]}, isbn = {0-7803-3095-1}, pages = {67 -- ff.}, year = {1996}, language = {en} } @article{FoersterDarmoDubeckyetal.1998, author = {F{\"o}rster, Arnold and Darmo, J. and Dubecky, F. and Kordos, P.}, title = {Annealing effect on concentration of EL6-like deep-level state in low-temperature-grown molecular beam epitaxial GaAs. Darmo, J.; Dubecky, F.; Kordos, P.; F{\"o}rster, A.}, series = {Applied Physics Letters. 72 (1998), H. 5}, journal = {Applied Physics Letters. 72 (1998), H. 5}, isbn = {1077-3118}, pages = {590 -- 592}, year = {1998}, language = {en} } @article{BreitbachAltesSzimmat1989, author = {Breitbach, Gerd and Altes, J. and Szimmat, J.}, title = {Anwendung der Finite-Element-Methode bei der Berechnung des W{\"a}rmetransports durch Strahlung / J. Altes ; G. Breitbach ; J. Szimmat}, series = {International FEM-Congress : Baden-Baden, Federal Republic of Germany, 17./18. November 1986}, journal = {International FEM-Congress : Baden-Baden, Federal Republic of Germany, 17./18. November 1986}, publisher = {IKO Software Service GmbH}, address = {Stuttgart}, pages = {127 -- 148}, year = {1989}, language = {de} }