Energie und Mobilität
Refine
Year of publication
Document Type
- conference proceeding (article) (168)
- Article (143)
- Part of a Book (41)
- conference talk (32)
- Report (19)
- conference proceeding (presentation, abstract) (8)
- Book (7)
- Master's Thesis (4)
- Preprint (4)
- Part of Periodical (3)
- Edited collection (1)
- Review (1)
Is part of the Bibliography
- no (431)
Keywords
- Energiewende (27)
- Erneuerbare Energien (27)
- Klimaneutralität (22)
- Power-to-Gas (21)
- Sektorenkopplung (16)
- Energiespeicher (14)
- Power-to-X (9)
- Wasserstoff (8)
- Netzplanung (7)
- Blindleistung (6)
Institute
- Fakultät Elektro- und Informationstechnik (240)
- Fakultät Maschinenbau (155)
- Forschungsstelle für Energienetze und Energiespeicher (FENES) / Forschungsgruppe Energiespeicher (76)
- Combustion Engines and Emissions Control Laboratory (CEEC) (40)
- Forschungsstelle für Energienetze und Energiespeicher (FENES) / Forschungsgruppe Energienetze (38)
- Labor Elektrische Maschinen und Antriebstechnik (37)
- Computational Mechanics and Materials Lab (CMM) (20)
- Technologie-Campus Neustadt an der Donau (20)
- Labor Intelligente Materialien und Strukturen (17)
- Fakultät Informatik und Mathematik (15)
Begutachtungsstatus
- peer-reviewed (187)
- begutachtet (15)
Ammonia-based selective catalytic reduction (SCR) systems are the most widely used technology for reduction of nitrogen oxide emissions from lean-burn engines such as diesel engines. However, at low exhaust temperatures, the SCR process is limited by difficulties in the decomposition of the ammonia precursor urea, which is carried on-board using an aqueous solution "AdBlue". In this study, the decomposition of AdBlue urea induced by electrical current and the resulting associated pH shifts were investigated in a divided cell configuration in the liquid phase. The decomposition was found to be favored in both electrochemical compartments, anodic and cathodic, at temperatures of 60-80 degrees C compared to a reference without electrochemical treatment. In addition to the determination of ammonia contents using an ammonia sensor, IC/HPLC analyses were carried out for each sample. Different side products such as biuret, nitrate, cyanuric acid, ammelide, and others were formed. In the anodic compartment, nitrate formation could be observed due to oxidation of ammonia at the electrode surface.
[GRAPHICS]
.
The purpose of this study was to investigate the characteristic of nanoparticles under consideration of sub-23-nm particles from a 1.8-l direct injection (DI) gasoline engine under stoichiometric air/fuel conditions in the exhaust gas system. For future CO2 challenges, the usage of DI-instead of port fuel injection (PFI)-gasoline engines is unavoidable. Therefore, a state of the art particle management program-particle number (PN) system, the Horiba SPCS (2100) with an integrated CPC (condensation particle counter), was recalibrated from a 50% cutoff (D-50%) at 23 nm down to a cutoff at 10 nm and the PCRF (particle concentration reduction factor) for sizes smaller than 23 nm was checked. Two different modal points, out of a representative Real Driving Emission (RDE) cycle, were investigated with both calibrations, D-50%=10 nm and D-50%=23 nm. For these different load points, the fuel pressure (FUP) and the start of injection (SOI) were varied, to represent the difference in the structure and the ratio conc((10 nm))/conc((23 nm)) of the nanoparticle emissions. The particle characterization includes the particle number (PN), the particle size distribution (PSD), and the particle mass (PM). The particle number was measured with Horiba SPCS (2100). The particle size distribution was analyzed with a Grimm differential mobility analyzer (DMA) in combination with a Faraday cup electrometer (FCE). Micro Soot and Pegasor were used to determine the PM, and an optical characterization was done with a 120-kV Phillips CM12 transmission electron microscope (TEM). The position of all particle measurement systems was downstream the three-way catalyst (TWC). The results of this investigation showed that a higher injection pressure decreases the PN (without consideration of sub-23-nm particles) in general. The ratio conc((10 nm))/conc((23 nm)) was therefore higher, because smaller particles, especially ash particles, were less reduced from the FUP. This means higher FUP tends to a higher ratio. For the SOI, the main reasons of the ratio differences were explained by an encroachment between the injection jet and the piston, the valve and the wall.
Basics for inline measurement of tribological conditions in series production of car body parts
(2019)
The quality of car body parts in series production is strongly dependent on the tribological behavior. Fluctuating material properties such as the sheet roughness and the amount of lubricant have an influence on the forming process. On the basis of large amounts of data it is possible to investigate the friction behavior in series production and to make process adjustments if required. Therefore, inline measurement systems have a great potential to detect the sheet roughness during the cutting process of blanks in the coil line. Furthermore, contactless systems are advantageous as they do not damage the surface. Nevertheless, the optical measuring is influenced by the lubricant layer on top of the surface. Therefore, the previously unknown impact of the lubricant on the measuring result is investigated.
Within this study, stationary optical roughness measurements have been conducted using different amounts of lubricant on hot-dip galvanized EDT steel. The results demonstrate the influence of different amounts of lubricant on the sheet roughness measurement. Hence, it is possible to correct the inline measuring results and gain knowledge of fluctuating surface roughness. In addition, strip drawing test has been carried out to investigate the effect of fluctuating tribological conditions.
As part of a systematic approach towards the search for alternative absorption heat pump (AHP) working pairs that could potentially provide comparable performance to conventional ones, a previous work performed a detailed theoretical cycle analysis and simulation that revealed concrete correlations between key working fluid thermophysical properties and AHP performance indicators. Following this work, targeted combinations of two organic refrigerants, 2,2,2-trifluoroethanol (TFE) and 2,2,3,3,3-pentafluoropropanol (5FP) and two organic absorbents, 1,3-dimethyl-2-imidazolidinone (DMI) and 2-pyrrolidone (PYR) were tested in a prototype 5 kW AHP, based on a highly compact plate heat exchanger design, which has been previously introduced. The purpose of this effort was to test the findings of the previous work with experimental measurements. The working pair combinations were also subjected to vapor liquid equilibrium (VLE) and viscosity measurements, in order to determine reliable activity coefficient and improve the accuracy of the simulations. The experimental performance data agree well with the COP simulations and show to be consistent with the conclusions derived from the previous theoretical work.
There are several approaches to classifying energy storage systems (see Chaps. 1 and 2). Storage systems are used in a large number of different technologies at various stages of development, and in a wide range of application areas (see Chaps. 3 to 5). This chapter compares the capabilities of the different storage systems using the following criteria:This comparison of storage systems also provides a convenient overview of the various storage systems and their capabilities.
Coupling energy sectors within the emerging residential PV prosumer systems is necessary for an optimised use of the houseowners’ own produced electricity. But the pure availability of different energy technologies in the system is not enough. By optimising the electricity usage as well as the capacities of PV generators, storage technologies, heat pumps and battery electric vehicles, not only the best solution in a technical point of view can be achieved, the need of finding the most financially beneficial system composition for single-family houses and tenements is possible. The study provides a detailed model for average German single-family houses and tenements and results for the energy transition period until 2050 for the optimised energy systems regarding optimised PV and stationary battery capacities and different heat storage capacities. Most noticeable outcomes can be observed by using a vehicle-to-home car, where a car can mostly take over the tasks of a stationary battery and by introducing a solidarity model using this type of car in tenement systems.
Diese Arbeit befasst sich mit automatisierten Netzplanungsprozessen und gibt einen kurzen Einblick in das Entscheidungsunterstützungssystem, 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 Verfügung stehen. Die vorgestellten Methoden und Algorithmen fokussieren sich auf die Q(U)- und coscp(P)-Regelungsarten.
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.
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.
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.
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.
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.
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.
Der Anteil fluktuierender erneuerbarer Energien im deutschen Strommix steigt. Um die Netzstabilität zu erhalten, Fluktuationen im Dargebot nach Wetterlage und saisonal auszugleichen sind absehbar ab ca. 2030 große Stromspeicherkapazitäten erforderlich. Wasser-Pumpspeicherwerke sind derzeit die einzige langjährig erprobte Technologie, die künftig in Braunkohletagebauen, welche im Zuge der Energiewende aufgegeben werden, errichtet werden könnten. Eine Überschlagsrechnung am Beispiel eines Pumpspeicherwerks in verschiedenen Tagebauen zeigt, dass diese mit bis zu 400 GWh ein signifikantes technisches Speicherpotenzial haben.