TY - JOUR A1 - Kramer, Kevin T1 - Water wheels for energy recovery in the outlet of wastewater treatment plants - Using the example of the water wheel at the Warendorf central wastewater treatment plant JF - Educational Journal of Renewable Energy Short Reviews N2 - The annual wastewater flow that is treated by public wastewater treatment plants in Germany amounts to approx. 10 ∗ 10^9 m3/a and forms an ”artificial” hydropower potential that can be used for energy generation or recovery. In the context of this paper, energy recovery in the outlet of wastewater treatment plants is examined using the specific example of the water wheel at the Warendorf central wastewater treatment plant. The ”artificial” hydropower potential can be roughly estimated at up to 20 to 105 GWh/a , whereby this is largely dependent on the hydraulic gradient. The strong variance results, among other things, from the findings of the water wheel operation in Warendorf. The decisive aspect here is the differential factor, which describes the deviation between the theoretical and actual energy yield of the water wheel. The factor includes maintenance work, downtimes and insufficient inflows, which are associated with a loss of output. In the case study, the annual energy recovery amounts to approx. 2 % of the annual electricity consumption of the wastewater treatment plant and can be estimated to 23,500 kWh (2022). In the context of the economic analysis, it can be seen that despite the ”low” yield, economic operation is possible if the system is viewed as a long-term investment - payback period of the example is approx. 14,5 years. The 27-year operation (1996 - 2023) of the water wheel at the Warendorf central wastewater treatment plant confirms this and important findings on successful practical operation can be shown in the context of this paper. T3 - EGU Master Journal of Renewable Energy Short Reviews - 2024_05 KW - energy recovery KW - wastewater treatment plant KW - water wheel KW - potential KW - real example Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-176423 SP - 28 EP - 32 ER - TY - CHAP A1 - Mesenhöller, Eva A1 - Jacobs, Steffen A1 - Vennemann, Peter A1 - Hussong, Jeanette T1 - Unsteady Ventilation in a Scaled Room Model with Swirl Ceiling Diffusers T2 - CLIMA 2022 conference N2 - Mechanical ventilation of buildings is generally based on steadily operating systems. This field is well known and established. But, an approach based on time-varied supply flow rates might improve indoor air quality, comfort, and energy consumption. Typical time-scales of the variation are in the order of seconds or minutes. Until now, the effects of unsteady ventilation scenarios are not fully described and so, reliable dimensioning rules are missing. Hence, with a better understanding of the flow in unsteady ventilation, systems can be calculated and optimised. To understand the effective mechanisms and derive functional relations between the flow field and variation parameters, full-field optical flow measurements are executed with a particle image velocimetry (PIV) system. Experiments are conducted under isothermal conditions in water in a small-scale room model (1.00 m × 0.67 m × 0.46 m) with two swirl ceiling diffusers, Reynolds-scaling assures similarity. In a series of experiments, the effects of different unsteady ventilation strategies on the flow fields are investigated and compared to steady conditions with the same mean exchange rate. Mean exchange rates, signal types, periods, and amplitudes are varied. Time-averaged normalised velocity fields already indicate notable differences between steady and unsteady cases especially for lower exchange rates: the distribution is more homogeneous in unsteady scenarios compared to steady conditions, and low-velocity areas are reduced while the mean velocity of the room increases. So, unsteady ventilation might be beneficial in terms of improved ventilation and energy savings in partial-load operation. Fast Fourier Transformation (FFT) analyses of the mean velocity for each field over the whole series detect the main frequency of the volume flow variation. By dividing the velocity field into smaller areas, this main frequency is still detected especially in the upper part of the room, but side frequencies play a role in the room as well. KW - unsteady ventilation KW - PIV KW - room airflow KW - mixing ventilation Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-151811 UR - https://proceedings.open.tudelft.nl/clima2022/article/view/200 PB - TU Delft OPEN CY - Delft ER - TY - CHAP A1 - Boiting, Bernd T1 - Thermische Batterien / Schwarmspeicher T2 - 16. Steinfurter Bioenergiefachtagung - Tagungsband N2 - Poster - Thermische Batterien / Schwarmspeicher Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-178343 SP - 1 CY - Steinfurt ER - TY - RPRT A1 - Hinse, Michael T1 - The Wells turbine: state of the art N2 - The first oscillating water column was invented in 1940. In the past decades the need of wave energy systems has significantly increased. This article quickly describes the Wells turbine and possibilities to enhance its performance and should answer the question: what are the design parameters that can be optimized? Furthermore it gives a small outlook about the history of oscillating Water Columns. T3 - EGU Master Journal of Renewable Energy Short Reviews - 2021_12 KW - wells turbine KW - owc KW - energy KW - oscillating water column KW - optimization Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-136861 ER - TY - JOUR A1 - Klemm, Christian A1 - Becker, Gregor A1 - Tockloth, Jan N. A1 - Budde, Janik A1 - Vennemann, Peter T1 - The Spreadsheet Energy System Model Generator (SESMG): A tool for the optimization of urban energy systems JF - Journal of Open Source Software N2 - The Spreadsheet Energy System Model Generator (SESMG) is a tool for modeling and optimizing energy systems with a focus on urban systems. The SESMG is easily accessible as it comes with a browser-based graphical user interface, spreadsheets to provide data entry, and detailed documentation on how to use it. Programming skills are not required for the installation or application of the tool. The SESMG includes advanced modeling features such as the application of the multi-energy system (MES) approach, multi-objective optimization, model-based methods for reducing computational requirements, and automated conceptualization and result processing of urban energy systems with high spatial resolution. Due to its accessibility and the applied modeling methods, urban energy systems can be modeled and optimized with comparatively low effort. Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-170845 SN - 2475-9066 VL - 8 IS - 89 SP - 5519 ER - TY - JOUR A1 - Hörnschemeyer, Birgitta A1 - Söfker-Rieniets, Anne A1 - Niesten, Jan A1 - Arendt, Rosalie A1 - Kleckers, Jonas A1 - Klemm, Christian A1 - Stretz, Celestin Julian A1 - Reicher, Christa A1 - Grimsehl-Schmitz, Winona A1 - Wirbals, Daniel A1 - Bach, Vanessa A1 - Finkbeiner, Matthias A1 - Haberkamp, Jens A1 - Budde, Janik A1 - Vennemann, Peter A1 - Walter, Gotthard A1 - Flamme, Sabine A1 - Uhl, Mathias T1 - The ResourcePlan — An Instrument for Resource-Efficient Development of Urban Neighborhoods JF - Sustainability N2 - In Germany, the current sectoral urban planning often leads to inefficient use of resources, partly because municipalities lack integrated planning instruments and argumentation strength toward politics, investors, or citizens. The paper develops the ResourcePlan as (i) legal and (ii) a planning instrument to support the efficient use of resources in urban neighborhoods. The integrative, multi-methodological approach addresses the use of natural resources in the building and infrastructural sectors of (i) water (storm- and wastewater) management, (ii) construction and maintenance of buildings and infrastructure, (iii) urban energy system planning, and (iv) land-use planning. First, the development as legal instrument is carried out, providing (i) premises for integrating resource protection at all legal levels and (ii) options for implementing the ResourcePlan within German municipal structures. Second, the evaluation framework for resource efficiency of the urban neighborhoods is set up for usage as a planning instrument. The framework provides a two-stage process that runs through the phases of setting up and implementing the ResourcePlan. (Eco)system services are evaluated as well as life cycle assessment and economic aspects. As a legal instrument, the ResourcePlan integrates resource protection into municipal planning and decision-making processes. The multi-methodological evaluation framework helps to assess inter-disciplinary resource efficiency, supports the spatial identification of synergies and conflicting goals, and contributes to transparent, resource-optimized planning decisions. KW - resource efficiency KW - resource management KW - urban neighborhood KW - urban planning KW - urban development Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-148545 VL - 14 IS - 3 PB - MDPI ER - TY - CHAP A1 - Buitink, Martin A1 - Hageman, Simon A1 - van Leeuwen, Richard T1 - The effect of the configuration of a heat exchanger in a thermal storage T2 - 16. Steinfurter Bioenergiefachtagung - Tagungsband N2 - Poster - The effect of the configuration of a heat exchanger in a thermal storage Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-178366 SP - 1 CY - Steinfurt ER - TY - RPRT A1 - Häner, Jurek T1 - Technologisches Lernen im Bereich Windenergie an Land N2 - Diese Arbeit befasst sich mit Kostentrends in Zusammenhang mit technologischem Lernen von Windenergie an Land in den USA, in Deutschland und weltweit. Ziel dieser Arbeit ist es, eine Lernkurve für Windenergie an Land zu bestimmen. Dafür wurden Daten zu Stromgestehungskosten (LCOE) und Kosten für die Installation (COP) von Windenergieanlagen (WEA) im Zeitraum von 1983 bis einschließlich 2020 gesammelt, grafisch dargestellt und weitergehend ausgewertet. Die grafische Darstellung der Datenlage verdeutlicht die zeitliche Entwicklung der Technologie. Zur Beschreibung dieser Lernkurven wurden die Progress Ratio (PR) und Learning Rate (LR) in fünf unterschiedlichen Modellen bestimmt. Anhand derer sich in Kombination mit der zukünftig installierten Leistung von WEA eine Prognose über zukünftige Kosten ableiten lässt. Die ermittelten LR bewegen sich zwischen 13 % und 28 %, woraus sich LCOE im Jahr 2030 zwischen 44,03 US$/MWh und 61 US$/MWh ergeben. T3 - EGU Master Journal of Renewable Energy Short Reviews - 2021_07 KW - Wind energy KW - Technological Learning KW - renewable energy KW - Levelized cost of energy Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-136814 ER - TY - JOUR A1 - Brinkschmidt, Florian T1 - Technologies for structural health monitoring of wind turbine blades - An overview of different techniques JF - Educational Journal of Renewable Energy Short Reviews N2 - Wind turbine structures take a major role in the modern conversion to renewable energy sources and contribute to the creation of a greener world. In recent years, the development and installation of wind turbines have seen rapid growth. However, with the increasing capacity and size of wind farms worldwide, there are growing concerns about the safety and reliability of these installations. Therefore, structural health monitoring and the detection of damage to wind turbines have gained considerable importance in research. Wind turbine blades are particularly susceptible to various types of damage due to environmental influences. This article provides an overview of signal responses, sensors used and non-destructive testing techniques in the field of damage detection on wind turbine blades. The intention of the article is to give an insight into the possibilities of structural health monitoring and at the same time to point out unsolved problems in this field. T3 - EGU Master Journal of Renewable Energy Short Reviews - 2024_03 KW - structural health monitoring KW - wind turbine blades KW - damage detection KW - measurement KW - non-destructive testing Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-176401 SP - 14 EP - 21 ER - TY - RPRT A1 - Tillenburg, Dennis T1 - Technical challenges of floating offshore wind turbines - An overview N2 - Floating offshore wind (FOW) holds the key to 80 % of the total offshore wind resources, located in waters of 60 m and deeper in European seas, where traditional bottom-fixed offshore wind (BFOW) is not economically attractive. Many problems affecting floating offshore wind turbines (FOWT) were quickly overcome based on previous experience with floating oil rigs and bottom-fixed offshore wind. However, this technology is still young and there are still many challenges to overcome. This paper shows that electrical failures are amongst the most significant errors of FOWT. The most common cause was corrosion. It is also stated that the control system is most often affected, and that the Generator is frequently involved. Material corrosion is also the key factor when it comes to the most common overall reason for failures. A particular attention must be paid to mooring line fracture. Mooring lines are especially vulnerable to extreme sea conditions and the resulting fatigue, corrosion, impact damage, and further risks. It must be stated that the primary challenge is that of economics. Over time technological costs will decline making FOW more competitive and hence attractive for greater depth. T3 - EGU Master Journal of Renewable Energy Short Reviews - 2021_03 KW - floating offshore wind power KW - challenges KW - wind turbine KW - mooring line KW - Windkraftanlage Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-136770 ER -