@unpublished{GaertnerMarxSchubachGadereretal., author = {G{\"a}rtner, Sebastian and Marx-Schubach, Thomas and Gaderer, Matthias and Schmitz, Gerhard and Sterner, Michael}, title = {Introduction of an Innovative Energy Concept for low Emission Glass Melting based on Carbon Capture and Usage}, doi = {10.31224/2642}, abstract = {Due to the very high fossil energy demand, the glass industry is looking for innovative approaches for the reduction of CO2 emissions and the integration of renewable energy sources. In this paper, we present a novel power-to-gas concept, which has no impact on established melting processes and discuss it for this purpose. A special focus is set on the required CO2 capture from typical flue gases in the glass industry, as this process has not been investigated in detail yet. We used a process simulation approach to investigate post-combustion CO2 capture by absorption processes, followed by a techno-economic evaluation. Our investigations found the designed CO2 capture plant to be approx. 400 times smaller than absorption based CO2 separation processes for conventional power plants. Due to the many options for waste heat utilization, the waste heat required for CO2 desorption can be generated in a particularly efficient and cost-effective way. The resulting CO2 avoidance costs range between 41-42 €/t CO2, depending on waste heat utilization for desorption, and thus offer a cost effective way of CO2 removal from glass industry melting processes. These costs are well below the values of 50-65 €/t CO2 described so far for comparable industrial applications. In addition, we describe optimization options, like solvent and process improvements, to enable further cost reductions. These results motivate further research and development on the overall process presented in this work.}, language = {en} } @article{KaulBoellmannThemaetal., author = {Kaul, Anja and Boellmann, Andrea and Thema, Martin and Kalb, Larissa and Stoeckl, Richard and Huber, Harald and Sterner, Michael and Bellack, Annett}, title = {Combining a robust thermophilic methanogen and packing material with high liquid hold-up to optimize biological methanation in trickle-bed reactors}, series = {Bioresource technology}, volume = {345}, journal = {Bioresource technology}, publisher = {Elsevier}, doi = {10.1016/j.biortech.2021.126524}, abstract = {The hydrogen gas-to-liquid mass transfer is the limiting factor in biological methanation. In trickle-bed reactors, mass transfer can be increased by high flow velocities in the liquid phase, by adding a packing material with high liquid hold-up or by using methanogenic archaea with a high methane productivity. This study developed a polyphasic approach to address all methods at once. Various methanogenic strains and packings were investigated from a microbial and hydrodynamic perspective. Analyzing the ability to produce high-quality methane and to form biofilms, pure cultures of Methanothermobacter performed better than those of the genus Methanothermococcus. Liquid and static hold-up of a packing material and its capability to facilitate attachment was not attributable to a single property. Consequently, it is recommended to carefully match organism and packing for optimized performance of trickle-bed reactors. The ideal combination for the ORBIT system was identified as Methanothermobacter thermoautotrophicus IM5 and DuraTop (R).}, language = {en} } @inproceedings{KreuzerHaslbeckBrueckl, author = {Kreuzer, Reinhard and Haslbeck, Matthias and Br{\"u}ckl, Oliver}, title = {Modellierung von Mittelspannungsnetzen zur verbesserten Nachbildung von Wirk- und Blindleistungsfl{\"u}ssen}, series = {Tagungsband der Fachtagung "Zuk{\"u}nftige Stromnetze f{\"u}r erneuerbare Energien" am 30./31. Januar 2018 in Berlin}, booktitle = {Tagungsband der Fachtagung "Zuk{\"u}nftige Stromnetze f{\"u}r erneuerbare Energien" am 30./31. Januar 2018 in Berlin}, abstract = {Das vom BMWi gef{\"o}rderte Forschungsprojekt SyNErgie (03/2015 bis 05/2018) besch{\"a}ftigt sich mit der Weiterentwicklung von Netzplanungsprozessen [1]. Im Fokus steht dabei die Modellierung von Blindleistungsfl{\"u}ssen und die dezentrale Nutzung von Blindleistungsquellen (z. B. Wechselrichter, Ladedrosseln, Kondensatoren) in Mittelspannungsnetzen, {\"u}ber welche der Blindleistungshaushalt letztendlich beeinflusst werden soll. Im Rahmen dieses Beitrags wird anhand eines realen Mittelspannungsnetzes (MS-Netz) gezeigt, welche Modellierungsschritte zur Erstellung eines m{\"o}glichst realit{\"a}tsnahen Simulationsabbilds n{\"o}tig sind. Dies ist notwendig, um der Verteilnetzplanung eine robuste Planungsgrundlage f{\"u}r die Ableitung von Entscheidungen im Rahmen eines Blindleistungsmanagements zur Verf{\"u}gung zu stellen.}, language = {de} } @inproceedings{RauchBrueckl, author = {Rauch, Johannes and Br{\"u}ckl, Oliver}, title = {Entwicklung eines Regelverfahrens f{\"u}r einen optimierten und zentralen Blindleistungsabruf zur Beeinflussung des Blindleistungshaushaltes von Mittelspannungsverteilungsnetzen unter Einhaltung von Netzrestriktionen}, series = {Zuk{\"u}nftige Stromnetze, 30.-31.Jan.2019, Berlin}, booktitle = {Zuk{\"u}nftige Stromnetze, 30.-31.Jan.2019, Berlin}, publisher = {Conexio}, address = {Pforzheim}, pages = {421 -- 437}, language = {de} } @article{Brueckl, author = {Br{\"u}ckl, Oliver}, title = {Pl{\"a}doyer f{\"u}r die wettbewerbliche Bereitstellung von Blindleistung}, series = {ew - Magazin f{\"u}r die Energiewirtschaft - Spezial: Digitalisierung}, volume = {117}, journal = {ew - Magazin f{\"u}r die Energiewirtschaft - Spezial: Digitalisierung}, number = {1}, publisher = {VDE Verlag}, organization = {VDE Verlag}, pages = {46 -- 48}, language = {de} } @inproceedings{Haslbeck, author = {Haslbeck, Matthias}, title = {Innovative Aspekte der Netzplanung im Verteilungsnetz}, series = {2. OTTI-Konferenz Zuk{\"u}nftige Stromnetze f{\"u}r Erneuerbare Energien, Hilton-Hotel Berlin, 27./28. Januar 2015}, booktitle = {2. OTTI-Konferenz Zuk{\"u}nftige Stromnetze f{\"u}r Erneuerbare Energien, Hilton-Hotel Berlin, 27./28. Januar 2015}, address = {Regensburg}, organization = {Ostbayerisches Technologie-Transfer-Institut (OTTI)}, isbn = {978-3-943891-46-1}, pages = {110 -- 115}, abstract = {In den Verteilungsnetzen (VN) besteht erheblicher Optimierungsbedarf, um die geplanten Leistungen an dezentralen Erzeugungsanlagen (EZA) aufnehmen und um die erzeugte Energie an das {\"U}bertragungsnetz abgeben zu k{\"o}nnen. Bislang konnte der Aufwand f{\"u}r die Netzplanung im VN mittels standardisierter Abl{\"a}ufe und großz{\"u}gigen Reserven im Spannungsband und der Stromtragf{\"a}higkeit begrenzt werden. Im Zuge des Zubaus an EZA schwinden diese Reserven und Netzplanungsaufgaben m{\"u}ssen individueller f{\"u}r einzelne Netzabschnitte gel{\"o}st werden. Die Forschungsstelle f{\"u}r Energienetze und Energiespeicher (FENES) der OTH Regensburg besch{\"a}ftigt sich u. a. mit der Fragestellung wie die Netzplanung im Verteilungsnetz hinsichtlich der neu entstandenen Herausforderungen optimiert werden kann und gleichzeitig praktikabel bleibt. Kernthemen sind dabei das Spannungs- und das Blindleistungsmanagement im Verteilungsnetz. Im Zuge der Energiewende gilt es die vorhandene Netzinfrastruktur noch effizienter auszunutzen und den Ausbau noch st{\"a}rker bedarfsorientiert zu gestalten. Infolgedessen bewegt sich der Netzbetrieb n{\"a}her an den Grenzen der Netzparameter (z. B. Spannungshaltung und Auslastung). Von daher m{\"u}ssen bislang praktizierte Verfahren weiter entwickelt werden, , um weiterhin einen sicheren und stabilen Netzbetrieb zu gew{\"a}hrleisten.}, language = {de} } @misc{Sterner, author = {Sterner, Michael}, title = {Insight into Power-to-Gas/Liquids: a solution for sustainable transport besides e-mobility}, series = {Conference Low Carbon Transport - Engineering the Fuels of the Future (Institution of Mechanical Engineers), London 09.07.2019}, journal = {Conference Low Carbon Transport - Engineering the Fuels of the Future (Institution of Mechanical Engineers), London 09.07.2019}, publisher = {Institution of Mechanical Engineers}, address = {London}, language = {en} } @inproceedings{KrausGschossmannBrueckl, author = {Kraus, Hermann and Gschoßmann, David and Br{\"u}ckl, Oliver}, title = {Automatisierung von Netzplanungsprozessen in der Verteilnetzebene - Q(U)- und cosj(P)-Blindleistungsregelung dezentraler Anlagen als spannungshaltende Netzausbaumaßnahmen}, series = {Tagungsband Zuk{\"u}nftige Stromnetze 2019, 30.-31.Jan.2019, Berlin}, booktitle = {Tagungsband Zuk{\"u}nftige Stromnetze 2019, 30.-31.Jan.2019, Berlin}, publisher = {Connexio}, address = {Pforzheim}, pages = {407 -- 420}, abstract = {Diese Arbeit befasst sich mit automatisierten Netzplanungsprozessen und gibt einen kurzen Einblick in das Entscheidungsunterst{\"u}tzungssystem, welches im EU-Projekt CrossEnergy entwickelt wird. Detaillierter wird aber auf die Konzipierung und Umsetzung eines automatisierten Einsatzes der Blindleistungsregelung von dezentralen Erzeugungs­ analgen eingegangen, die als spannungshaltende Netzausbaumaßnahme zur Verf{\"u}gung stehen. Die vorgestellten Methoden und Algorithmen fokussieren sich auf die Q(U)- und coscp(P)-Regelungsarten.}, language = {de} } @techreport{SternerThemaEckertetal., author = {Sterner, Michael and Thema, Martin and Eckert, Fabian and Moser, Albert and Sch{\"a}fer, Andreas and Drees, Tim and Christian Rehtanz, and Ulf H{\"a}ger, and Kays, Jan and Seack, Andr{\´e} and Dirk Uwe Sauer, and Matthias Leuthold, and Philipp St{\"o}cker,}, title = {Stromspeicher in der Energiewende - Untersuchung zum Bedarf an neuen Stromspeichern in Deutschland f{\"u}r den Erzeugungsausgleich, Systemdienstleistungen und im Verteilnetz}, publisher = {Agora Energiewende}, address = {Berlin}, doi = {10.13140/RG.2.2.31804.56964}, abstract = {Wie groß ist der Speicherbedarf in Deutschland in der weiteren Umsetzung der Energiewende? Welche Rolle spielen Batteriespeicher, Pumpspeicher, Power-to-Gas etc. im Kontext anderer Flexibilit{\"a}tsoptionen auf den verschiedenen Netzebenen? Wie entwickelt sich der Markt f{\"u}r Batterien und Wasserstoff? In unserer Agora-Speicherstudie haben wir auch erstmalig den Begriff Power-to-X definiert und damit die bis dato entstandenen Begriffe Power-to-Gas, Power-to-Liquids, Power-to-Products, Power-to-Chemicals etc. zusammengefasst.}, language = {de} } @incollection{StadlerEckert, author = {Stadler, Ingo and Eckert, Fabian}, title = {Lastmanagement als Energiespeicher}, series = {Energiespeicher - Bedarf, Technologien, Integration}, booktitle = {Energiespeicher - Bedarf, Technologien, Integration}, editor = {Sterner, Michael and Stadler, Ingo}, edition = {2. Auflage}, publisher = {Springer Vieweg}, address = {Berlin ; Heidelberg}, isbn = {978-3-662-48893-5}, doi = {10.1007/978-3-662-48893-5_11}, pages = {619 -- 644}, subject = {Lastverteilung }, language = {de} } @incollection{SternerEckertHenningetal., author = {Sterner, Michael and Eckert, Fabian and Henning, Hans-Martin and Trost, Tobias}, title = {Storage Demand in the Transport and Chemical Sector}, series = {Handbook of Energy Storage}, booktitle = {Handbook of Energy Storage}, editor = {Sterner, Michael and Stadler, Ingo}, publisher = {Springer}, address = {Berlin, Heidelberg}, isbn = {978-3-662-55503-3}, doi = {10.1007/978-3-662-55504-0_5}, pages = {165 -- 188}, abstract = {In the transport sector, energy transition is still in its beginnings: shares of renewable fuels are at 5\% and are, with the exception of a small percentage in electrical rail transport, almost entirely restricted to biofuel. The transport sector, i.e., road, air, shipping, and rail traffic, consumes around 30\% of all final energy in Germany and its dependency of over 90\% on petroleum is still very high. As a result, its shares in greenhouse gas emissions are at 20\%. The necessary structural change in mobility, based on energy transition, is closely linked to the question of operating energy and of energy storage also. Aside from vehicles directly powered by wind or solar energy, mobility without storage is not possible: fuel tanks in cars, gas stations, and airplanes are omnipresent. The focus of the considerations on storage demand in the transport sector is on the question of how these storages can be used with renewable energies via bio and synthetic fuels, and on the question of how much storage is necessary for these new drive technologies, such as e-mobility. Before this, mobility needs today and in future need to be examined. In the chemical sector, the situation is very much alike: there is a great dependency on fossil resources, and decarbonization is inevitable to achieve ambitious climate goals. The structural change to convert and store renewable electricity as primary energy via power-to-X (PtX) represents a storage demand. First estimates will conclude this chapter.}, language = {en} } @incollection{SternerBreuerDreesetal., author = {Sterner, Michael and Breuer, Christopher and Drees, Tim and Eckert, Fabian and Maaz, Andreas and Pape, Carsten and Rotering, Niklas and Thema, Martin}, title = {Storage Demand in Power Supply}, series = {Handbook of Energy Storage}, booktitle = {Handbook of Energy Storage}, editor = {Sterner, Michael and Stadler, Ingo}, publisher = {Springer}, address = {Berlin, Heidelberg}, isbn = {978-3-662-55503-3}, doi = {10.1007/978-3-662-55504-0_3}, pages = {51 -- 136}, abstract = {Energy storage systems (in the past as well as today) are one significant part in the energy supply. The following three chapters describe how storage demand will develop in the future for the electricity, heat, and traffic sectors, as well as for non-energetic consumption of fossil resources (the chemical industry). Chapter 3, the core of this section on storage demand, makes clear how and why the electricity sector is the nucleus of the energy supply of all sectors and why it creates essential bridges between electricity, heat, and transport sectors, as well as with the chemical industry. If planned electricity network expansion takes place and flexibilities in generation and consumption are fully exploited, the demand for electricity storage, according to present estimates, will only reach a significant scale at 60-80\% shares of renewable energy in the power supply. Network expansion has a great impact on the storage demand, as well as flexible power generation in power plants, combined heat and power (CHP), and flexible consumption via demand-side management (DSM). Four studies in the context of storage demand and the role of energy storage systems for flexibility are comprehensively addressed. The authors and the co-authors were themselves participants in these studies, which will be complemented by ongoing research. A meta-study summary of the main results is shown in Abschn. 3.7, and these results are compared with seven further studies.}, language = {en} } @incollection{Sterner, author = {Sterner, Michael}, title = {Energy Storage Through the Ages}, series = {Handbook of Energy Storage}, booktitle = {Handbook of Energy Storage}, editor = {Sterner, Michael and Stadler, Ingo}, publisher = {Springer}, address = {Berlin, Heidelberg}, isbn = {978-3-662-55503-3}, doi = {10.1007/978-3-662-55504-0_1}, pages = {3 -- 22}, abstract = {Human beings have relied on stored energy since time immemorial. The planet's first mechanism for storing energy arose two billion years ago. Photosynthesis captures solar energy in chemical bonds; it is a process on which all life depends. With the discovery of fire around one-and-a-half million years ago, early man learned to access this stored energy by burning wood. Only since the Industrial Revolution have humans used fossil fuels, which are the results of biomass produced millions of years ago, then subjected to geological processes. Today, the long-term objective is to utilize sustainable biomass storage, replicate it by technical means, and to develop new storage technologies. This chapter is about the history of energy storage as it pertains to the carbon cycle. It begins with a natural energy storage system—photosynthesis—and examines its products biomass, peat, and fossil fuels before turning to storage technology in the era of renewable energies. It will also discuss how stored energy is used. This chapter focuses on natural biogenic and fossil energy storage. Other chapters are devoted to artificial storage technologies, including batteries, pumped-storage, and power-to-gas (PtG). Each begins with a short history of its respective technology.}, language = {en} } @incollection{SternerStadlerEckertetal., author = {Sterner, Michael and Stadler, Ingo and Eckert, Fabian and Gerhardt, Norman and von Olshausen, Christian and Thema, Martin and Trost, Tobias}, title = {Storage Integration for Coupling Different Energy Sectors}, series = {Handbook of Energy Storage}, booktitle = {Handbook of Energy Storage}, editor = {Sterner, Michael and Stadler, Ingo}, publisher = {Springer}, address = {Berlin, Heidelberg}, isbn = {978-3-662-55503-3}, doi = {10.1007/978-3-662-55504-0_14}, pages = {757 -- 803}, abstract = {Electricity is becoming the primary source of energy, a trend that is particularly apparent through the coupling of the electricity sector with other energy sectors. In addition to the established links between the electricity and heating sectors using combined heat and power (CHP), which is supplemented by electric heat-pumps and power-to-heat (PtH), other new links are also emerging. These links are manifesting in the form of electro-mobility and electric fuels in the electricity and transport sectors; and in the electricity and gas sector they are appearing in the form of power-to-gas (PtG). The production of basic chemical materials such as methanol or polymers using electrical energy, water, and CO2 will also play a role in the future. However, the latter will not be dealt with explicitly here. Instead we will consider in detail other aspects of electricity as a primary energy source and its integration and application for energy storage.}, language = {en} } @incollection{SternerStadlerEckertetal., author = {Sterner, Michael and Stadler, Ingo and Eckert, Fabian and Thema, Martin}, title = {Storage Integration in Individual Energy Sectors}, series = {Handbook of Energy Storage}, booktitle = {Handbook of Energy Storage}, editor = {Sterner, Michael and Stadler, Ingo}, publisher = {Springer}, address = {Berlin, Heidelberg}, isbn = {978-3-662-55503-3}, doi = {10.1007/978-3-662-55504-0_13}, pages = {675 -- 755}, abstract = {How is energy storage integrated and currently implemented in the electricity supply, heating supply, and mobility sectors? This chapter provides both theoretical and practical answers to that question. The chapter focuses on the integration of renewable energy. Cross-sectoral energy storage systems that link the electricity, heating, and mobility sectors are discussed in Kap. 14. This chapter focuses on storage integration in the electricity sector. After considering stand-alone networks, the chapter uses practical examples to analyze the various storage applications in the European network. The chapter concludes with a discussion of storage integration in the heating and transportation sectors.}, language = {en} } @incollection{SoergelRiedererHeldetal., author = {S{\"o}rgel, Matthias and Riederer, Michael and Held, Andreas and Plake, Daniel and Zhu, Zhilin and Foken, Thomas and Meixner, Franz X.}, title = {Trace Gas Exchange at the Forest Floor}, series = {Energy and Matter Fluxes of a Spruce Forest Ecosystem}, volume = {229}, booktitle = {Energy and Matter Fluxes of a Spruce Forest Ecosystem}, editor = {Foken, Thomas}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-49387-9}, doi = {10.1007/978-3-319-49389-3_8}, pages = {157 -- 179}, abstract = {Exchange conditions at the forest floor are complex due to the heterogeneity of sources and sinks and the inhomogeneous radiation but are important for linking soil respiration to measurements in the trunk space or above canopy. Far more attention has therefore been paid to above and within canopy flows, but even studies that addressed forest floor exchange do not present measurements below 1 m or 2 m. We used a multilayer model that explicitly resolves the laminar layer, the buffer layer, and the turbulent layer to calculate fluxes from the measured profiles in the lowest meter above ground and to calculate effective surface concentrations from given fluxes. The calculated fluxes were compared to measured eddy covariance fluxes of sensible heat and O3 and to chamber derived soil fluxes of CO2 and 222Rn. Sensible heat fluxes agreed surprisingly well given the heterogeneity of radiative heating and the generally low fluxes (max. 25 W m-2). The chamber fluxes turned out to be not comparable as the chamber fluxes were too low, probably due to one of the well-known problems of enclosures such as pressure differences, disturbed gradients and exclusion of naturally occurring turbulence events and surface cooling. The O3 fluxes agreed well for high O3 values reaching down to the forest floor during full coupling of the canopy by coherent structures. During most of the time, the model overestimated the fluxes as chemical reactions were dominating within the profile. One new approach was to calculate the effective surface concentration from a given flux and compare this to measured surface concentrations. This allowed the identification of situations with a coupled and decoupled forest floor layer, which has important consequences for respiration measurements in the trunk space or above canopy and should be considered in upcoming studies.}, language = {en} } @incollection{SternerBauer, author = {Sterner, Michael and Bauer, Franz}, title = {Definition and Classification of Energy Storage Systems}, series = {Handbook of Energy Storage}, booktitle = {Handbook of Energy Storage}, editor = {Sterner, Michael and Stadler, Ingo}, publisher = {Springer}, address = {Berlin, Heidelberg}, isbn = {978-3-662-55503-3}, doi = {10.1007/978-3-662-55504-0_2}, pages = {23 -- 47}, abstract = {Energy supply always requires energy storage—either as an intrinsic property or as additional system. It is an intrinsic property of solid, liquid, and gaseous fuels, although less so of water-borne heat, but not of electricity. So to meet variable demands and supplies, heat and electricity networks usually require additional storage systems. When they are added to an energy network, should they be viewed as 'suppliers' or as 'consumers'? Who is responsible for covering the costs of storage systems? To categorize storage systems in the energy sector, they first need to be carefully defined. This chapter defines storage as well as storage systems, describes their use, and then classifies storage systems according to temporal, spatial, physical, energy-related, and economic criteria.}, language = {de} } @incollection{StadlerSterner, author = {Stadler, Ingo and Sterner, Michael}, title = {Urban Energy Storage and Sector Coupling}, series = {Urban Energy Transition}, booktitle = {Urban Energy Transition}, editor = {Droege, Peter}, edition = {2. ed.}, publisher = {Elsevier}, isbn = {978-0-08-102074-6}, doi = {10.1016/B978-0-08-102074-6.00026-7}, pages = {225 -- 244}, abstract = {Global warming, greenhouse gas emissions, and the general transition toward renewable energy resources are mentioned many times within this book, and will not be repeated again here. Countries that are transitioning to use of more renewable energy sources are mainly using wind and solar power—except for a few countries that, due to their prerequisites, will mainly use hydro power and/or bioenergy. The transmission process in terms of energy generation so far is mainly happening in rural areas—not in urban centers. Most technologies do not really play an important role in urban areas, and are mainly focused on the application of solar energy. Solar energy is widely applied more in rural areas, although investigations show that its application in urban areas already fits well into the existing grid infrastructure. Whereas rural areas are more prone to grid integration problems, the energy infrastructure in urban centers is already well prepared for renewables integration. In fostering tight bundles of potentially linked energy generation, distribution, networking, and use across power and thermal systems in stationary and mobile modes, urban centers become particularly critical in the energy transition processes as energy systems are becoming completely based on renewable sources without a nuclear or fossil-based backbone. This chapter discusses the almost unlimited energy storage possibilities. It will show their enormous capabilities, but also their significant differences in many physical and economical parameters. Next, the authors discuss the necessity of combining and coupling the different energy sectors for electricity, heat, cold, gas, and transport. Finally, the authors present the conclusion that only when coupling the energy sectors and using cheap and efficient energy storage options from one energy sector to solve challenges within another energy sector will the energy transition process be managed in an efficient way.}, language = {en} } @article{ThemaThema, author = {Thema, Johannes and Thema, Martin}, title = {Nachnutzungskonzept: Braunkohle-Tagebaue als Pumpspeicherkraftwerk?}, series = {Energiewirtschaftliche Tagesfragen - et : Zeitschrift f{\"u}r Energiewirtschaft, Recht, Technik und Umwelt}, volume = {69}, journal = {Energiewirtschaftliche Tagesfragen - et : Zeitschrift f{\"u}r Energiewirtschaft, Recht, Technik und Umwelt}, number = {4}, publisher = {ETV Energieverl.}, address = {Essen}, pages = {38 -- 39}, abstract = {Der Anteil fluktuierender erneuerbarer Energien im deutschen Strommix steigt. Um die Netzstabilit{\"a}t zu erhalten, Fluktuationen im Dargebot nach Wetterlage und saisonal auszugleichen sind absehbar ab ca. 2030 große Stromspeicherkapazit{\"a}ten erforderlich. Wasser-Pumpspeicherwerke sind derzeit die einzige langj{\"a}hrig erprobte Technologie, die k{\"u}nftig in Braunkohletagebauen, welche im Zuge der Energiewende aufgegeben werden, errichtet werden k{\"o}nnten. Eine {\"U}berschlagsrechnung am Beispiel eines Pumpspeicherwerks in verschiedenen Tagebauen zeigt, dass diese mit bis zu 400 GWh ein signifikantes technisches Speicherpotenzial haben.}, language = {de} } @unpublished{KaulBoellmannThemaetal., author = {Kaul, Anja and B{\"o}llmann, Andrea and Thema, Martin and Kalb, Larissa and St{\"o}ckl, Richard and Huber, Harald and Sterner, Michael and Bellack, Annett}, title = {Identification of Robust Thermophilic Methanogenic Archaea and Packing Material for High Liquid Hold-Up at Low Volumetric Gas Flow Rates for Use in Trickle-Bed Reactors for Biological Methanation}, series = {SSRN Electronic Journal}, journal = {SSRN Electronic Journal}, doi = {10.2139/ssrn.3940878}, abstract = {he hydrogen gas-to-liquid mass transfer is the limiting factor in biological methanation. In a trickle-bed reactor, mass transfer can be increased by high flow velocities in the liquid phase, by adding a packing material with high liquid hold-up, or by choosing methanogenic archaea with a high methane productivity. This study analyzed various packings and methanogenic strains from a hydrodynamic and microbial perspective. By analyzing twelve pure cultures of thermophilic methanogens for their ability to produce high quality methane and to form biofilms on different packings, strains of Methanothermobacter were found to perform better than thus of the genus Methanothermococcus. Best methane production and adherence was observed on DuraTop®, Bioflow 9, and filter foam. DuraTop® and Bioflow 9 had also a high dynamic liquid hold-up, but the maximum hold-up was determined for expanded clay. The ideal combination for use in the ORBIT-trickle-bed reactor was identified as Methanothermobacter thermoautotrophicus IM5 and DuraTop®.}, language = {en} }