Fakultät 09 / Cologne Institute for Renewable Energy
Refine
Document Type
- Article (6)
- Other (4)
- Report (3)
- Part of a Book (2)
- Bachelor Thesis (1)
Has Fulltext
- yes (16)
Keywords
- Erneuerbare Energien (3)
- Smart Energy (3)
- Sonnenenergie (3)
- Agricultural Farms (2)
- Bifacial Photovoltaic (2)
- Bioenergie (2)
- Biogenic Residues (2)
- Biomasse (2)
- Energieeffizienz (2)
- Energiepflanzen (2)
Reducing the carbon emissions from hotels on non-interconnected islands (NII) is essential in the context of a low carbon future for the Mediterranean region. Maritime tourism is the major source of income for Greece and many other countries in the region, as well as hot-temperate and tropical regions worldwide. Like many NIIs, Rhodes attracts a high influx of tourists every summer, doubling the island’s energy demand and, given the high proportion of fossil fuels in the Rhodian energy supply, increasing carbon emissions. Using the theoretical framework ‘FINE’, this paper presents the optimisation of a medium-sized hotel’s energy system with the aim of reducing both cost and carbon emissions. By introducing a Photovoltaic (PV) net metering system, it was found that the carbon emissions associated with an NII hotel’s energy system could be reduced by 31% at an optimised cost. It is suggested that large-scale deployment of PV or alternative renewable energy sources (RES) in NII hotels could significantly reduce carbon emissions associated with the accommodation sector in Greece and help mitigate climate change.
Potential analyses identify possible locations for renewable energy installations, such as wind turbines and photovoltaic arrays. The results of previous potential studies for Germany, however, are not consistent due to different assumptions, methods, and datasets being used. For example, different land-use datasets are applied in the literature to identify suitable areas for technologies requiring open land. For the first time, commonly used datasets are compared regarding the area and position of identified features to analyze their impact on potential analyses. It is shown that the use of Corine Land Cover is not recommended as it leads to potential area overestimation in a typical wind potential analyses by a factor of 4.7 and 5.2 in comparison to Basis-DLM and Open Street Map, respectively. Furthermore, we develop scenarios for onshore wind, offshore wind, and open-field photovoltaic potential estimations based on land-eligibility analyses using the land-use datasets that were proven to be best by our pre-analysis. Moreover, we calculate the rooftop photovoltaic potential using 3D building data nationwide for the first time. The potentials have a high sensitivity towards exclusion conditions, which are also currently discussed in public. For example, if restrictive exclusions are chosen for the onshore wind analysis the necessary potential for climate neutrality cannot be met. The potential capacities and possible locations are published for all administrative levels in Germany in the freely accessible database (Tool for Renewable Energy Potentials—Database), for example, to be incorporated into energy system models.
Im Rahmen des Technologiescreenings sind zunächst relevante Technologien, die Einfluss auf das Energienachfrageverhalten für Haushalte besitzen, identifiziert worden. Dabei ist ausschließlich eine technologische Betrachtung erfolgt, das individuelle Nutzerverhalten von Haushaltsbewohnern wurde dabei nicht betrachtet. Die Einordnung der Technologien sind in Standard Energietechnologien: Erzeuger, Umwandler, Verbraucher und Speicher kategorisiert. Zudem zeigt die in die Kategorien Messsysteme, Gebäudeautomation und Energiemanagementsysteme. Dabei handelt es sich um, digitale Technologien mit Aspekten und Anwendungen von Energietransparenz und -management. Zeitraum des kontinuierlichen Technologie-Screenings war von 2017-2020.
This study aimed to simulate the sector-coupled energy system of Germany in 2030 with the restriction on CO2 emission levels and to observe how the system evolves with decreasing emissions. Moreover, the study presented an analysis of the interconnection between electricity, heat and hydrogen and how technologies providing flexibility will react when restricting CO2 emissions levels. This investigation has not yet been carried out with the technologies under consideration in this study. It shows how the energy system behaves under different set boundaries of CO2 emissions and how the costs and technologies change with different emission levels. The study results show that the installed capacities of renewable technologies constantly increase with higher limitations on emissions. However, their usage rates decreases with low CO2 emission levels in response to higher curtailed energy. The sector-coupled technologies behave differently in this regard. Heat pumps show similar behaviour, while the electrolysers usage rate increases with more renewable energy penetration. The system flexibility is not primarily driven by the hydrogen sector, but in low CO2 emission level scenarios, the flexibility shifts towards the heating sector and electrical batteries.
The utilization of roadside-green-cuttings (grass) for anaerobic digestion increases provides an additional possible source of organic waste for use as a renewable energy source. Grass can be used as a substrate to increase biogas yield. Nevertheless, the anaerobic digestion of this kind of waste can be limited due to the fact that it could be contaminated with heavy metals, in particular from traffic emissions and industrial activity. For this reason the biogas production of grass from a busy road was assessed. Samples of roadside-grass were washed with an organosulphide, which is used for the removal of heavy metals from wastewater.
A comparison of the anaerobic digestion of washed and unwashed roadside grass was performed. Results showed that the anaerobic digestion of the unwashed grass was much more effective than the washed grass. A second experiment was carried out and co-fermentation of manure and farm-grass was prepared for anaerobic digestion. Lead was added in the concentrations 500, 1000 and 2000 mg Pb2+/kg. The results showed that the higher the lead concentration, the lower the inhibition of the biogas yield. The grass could be acting as phytoremediator for high lead concentrations. The grass could contain organic compounds, which can as-similate heavy metals.
Intelligent use of energy is one of the keys to success for an energy revolution. To meet this challenge, smart meters are suitable tools because INTELLIGENT use of energy means not only to use efficiency technology, but also to determine load shifting potentials and use them accordingly. Especially farms with high power consumption are becoming increasingly concerned about reducing energy costs due to rising energy prices and need a systematic analysis of their operational energy flow. To find solutions for farms, the NaRoTec e.V., the TH Köln, and the Machinery Ring Höxter-Warburg have joined forces with partners and launched the project "Intelligent Energy in Agriculture", which is funded by the state of NRW in Germany. The aim of the project is to be able to give individual advice recommendations for energy optimization of agricultural holdings. This will be achieved inter alia through an operational energy audit and current measurements in different operating ranges. To achieve this, smart meters were installed in selected energy-intensive dairy and pig farms.
As part of the project, the installed smart meter information of one of the dairy Farms is used to optimize the energy consumption of the farm and increase the degree of self-sufficiency. A good way to achieve this is by taking a closer look at the cooling process of the produced milk since it is one of the most energy consuming processes on a dairy farm. In addition an installation of an ice cooling system instead of a direct cooling system enables the possibility to store self-produced energy in the form of ice and use it later on when it is needed to cool the milk. This flattens the usual energy peaks throughout the day and increases the degree of self-sufficiency. To ensure a sufficient amount of self-produced energy with solar power plants of various sizes were designed. The different sizes of the power plants are defined by the use of the gathered smart meter data is used to cover different electric loads in addition to the ice water cooling system. Afterwards the different simulated models are compared to find the best balance between energy production, investment cost and a high degree of self-sufficiency. First results show that using an ice cooling system in combination with a solar power plant improvement the degree of self-sufficiency by up to 7.8 %.
Das interdisziplinäre Forschungsprojekt “Smarte Technologien für Unternehmen” untersuchte im Zeitraum von Juli 2017 bis Dezember 2020 Anwendungs- und Akzeptanzprobleme zum Einsatz smarter Technologien in KMU und entwickelte darauf aufbauend Lösungsansätze zur Steigerung der Energieeffizienz sowie zum Energie- und Lastmanagement. Dazu wurden smarte Technologien zunächst im Zuge eines Screenings identifiziert, kategorisiert und bewertet. In den qualitativen und quantitativen Nutzeranalysen wurden Unternehmer*innen in den Fokus der Analyse gestellt, um den Wissensstand sowie Chancen und Barrieren zum Einsatz smarter Technologien in KMU darzulegen. Mit der Durchführung transdisziplinärer Anwendungstests wurde ein zentraler Lösungsansatz entwickelt: Die Effizienzanalyse von KMU mittels mobiler Messtechnik und Visualisierungstools als potenzielle Strategie zur Reduktion von Energieverbräuchen.
Die Ergebnisse dieses anwendungsorientierten Forschungsprojektes zeigen die Anwendungs- und Akzeptanzprobleme zum Einsatz smarter Technologien in KMU auf und geben Handlungsoptionen zur Steigerung der Energieeffizienz mit Hilfe ausgewählter smarter Produkte und Tools.
Im Rahmen des Technologie-Screenings wurden smarte Technologien für den Einsatz in mittelständischen Unternehmen (vorzugsweise KMU) im Zeitraum von 2017-2020 in einem kontinuierlichen Monitoringprozess betrachtet. Dadurch konnte mit dem Screening ein umfassender Überblick über die Angebotsseite und den Markt smarter Technologien geschaffen werden. Ebenso wurden potenzielle Technologien für den Einsatz im Anwendungstest des Forschungsprojekts VISE-U identifiziert. Insgesamt umfasst das Technologie-Screening sechs spezifische Technologie-Kategorien, denen wiederum einzelne Systeme auf Herstellerebene zugeordnet wurden. So konnten in Summe 20 Systeme unterschiedlicher Hersteller hinsichtlich des Aufbaus sowie der Funktionsweise samt Technologie-Steckbrief beschrieben werden. Die Steckbriefe zeigen dazu die technische Beschreibung, Komponenten sowie Schnittstellen der Systeme auf und referenzieren auf weiterführende Informationen auf den Webseiten der Hersteller.
A bifacial Photovoltaic (PV) simulation model is created by combining the optical View Factor matrix with electrical output simulation in python to analyse the energy density of bifacial systems. A discretization of the rear side of the bifacial modules allows a further investigation of mismatching and losses due to inhomogeneous radiation distribution. The model is validated, showing a deviation of -1.25 % to previous simulation models and giving hourly resolvedoutput data with a higher accuracy than existing software for bifacial PV systems.
The annual yield of bifacial photovoltaic systems is highly dependent on the albedo of the underlying soil. There are currently no published data about the albedo of red soil in western Africa. In this study, the impact of the albedo of red soil in Ghana on the energy yield of bifacial photovoltaic systems is analysed. A bifacial photovoltaic simulation model is created by combining the optical view factor matrix with an electrical output simulation. For an exact simulation, the albedo of red soil at three different locations in Ghana is measured for the first time. The average albedo of every red soil is clearly determined, as well as the measurement span including instrumentation uncertainty; values between 0.175 and 0.335 were measured. Considering these data, a state-of-the-art bifacial photovoltaic system with an average of 19.8% efficient modules in northern Ghana can achieve an annual energy yield of 508.8 kWh/m2 and a bifacial gain of up to 18.3% in comparison with monofacial photovoltaic panels. To summarise, red soil in two out of three locations in Ghana shows higher albedo values than most natural ground surfaces and therefore positively impacts the annual yield of bifacial photovoltaic systems.