Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
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Master Thesis Modeling and Thermo-Economic Analysis of a Photovoltaic-Battery Hybrid Energy System: a Case Study in Yenikale Geothermal Heat Center(01. Izmir Institute of Technology, 2023) Gökçen Akkurt, Gülden; Helvacı, Hüseyin Utku; Gökçen Akkurt, Gülden; Helvacı, Hüseyin Utku; 01. Izmir Institute of Technology; 03.06. Department of Energy Systems Engineering; 03. Faculty of EngineeringWater is vital for agriculture accounting 50-70% of the total global use of fresh water for irrigation. Geothermal water as a renewable energy source is used to generate electricity, heat and cool. The remaining water can be desalinated to be used for agricultural irrigation. Energy demand of desalination systems is high and mostly rely on fossil fuels increasing cost and greenhouse gas emissions. Thus, renewable energy use in desalination process is increasing. Based on a research project, a pilot desalination system is installed in Yenikale Heat Center of Balcova-Narlidere Geothermal District Heating System to desalinate geothermal water and use for agricultural irrigation. The desalination system is powered by a solar PV system which meets energy need entirely in summer but only 30-50% in winter. The remaining energy need is supplied from the grid. The aim of this study is to maximize the utilization of solar energy for the desalination process while minimizing reliance on the grid. To achieve this objective, three different scenarios are analyzed based on three different solar radiation values of 2021 integrating a battery system. For each scenario; first, battery capacities and the number of PV panels are determined. Then, energy, exergy and exergo-economic analysis are conducted. The parameters calculated in economic analysis are net present value, payback period and cost of energy production. One of the main results obtained is the unit energy cost for solar driven desalination system 0.28 $/kWh which is in a good agreement with the literature (0.214-0.23 $/kWh).Master Thesis Synthesis of Indandione-Based Porous Organic Polymers and Their Applications in Zinc-Ion Batteries(01. Izmir Institute of Technology, 2022) Büyükçakır, Onur; Büyükçakır, Onur; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of TechnologyThere has been growing interest in porous organic polymers (POPs) in recent years due to their large surface area, easy chemical tunability, sustainability, and high thermal and chemical stability. Due to their exceptional properties, they are suitable for use as platforms in various applications, including gas storage, separation, catalysis, and, more recently, energy storage systems. In this regard, it is imperative to design new functional POPs with a large surface area, permanent porosity, and physicochemical stability. In this thesis, we have presented indandione-based POPs (r-POPs) prepared by an acid-catalyzed condensation reaction between s-indacene-1,3,5,7(2H,6H)-tetraone and benzene-1,3,5-tricarboxaldehyde under highly environmentally friendly conditions. In order to optimize the reaction conditions, we first synthesized the model compound, namely 2-benzylidene-1H-indene-1,3(2H)-dione. The model compound was characterized by using 1H and 13C-NMR spectroscopy. Using different types of acids, we have investigated the effect of acid on polymerization and its textural properties. The polymers were characterized using various characterization techniques. Due to increased interest in renewable energy as a fossil fuel substitute, energy storage systems have attracted colossal interest, and rechargeable aqueous zinc-ion batteries (ZIBs) are seen as promising energy storage systems, particularly for grid-scale applications. In this respect, the carbonyl-rich structure of r-POPs transforms them into a potential electrode material. Thus, we have also investigated their electrochemical performances as cathode materials for ZIBs. Although r-POPs showed low electrochemical performance in capacity and cycle life, they have great potential to be an electrode material in other metal-ion batteries.Master Thesis Synthesis and Characterization of Aluminum Doped To Extend Cathode Life in Li-Ion Batteries(01. Izmir Institute of Technology, 2021) Karabudak, Engin; Karabudak, Engin; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of TechnologyLithium-ion batteries have an important place in meeting the energy needs and are of greater importance than their cognates, thanks to their characteristics as secondary batteries. Volumetric and gravimetric energy densities are the main features that carry lithium-ion batteries to the top. Lithium-ion batteries consist of different parts: cathode, anode, separator and electrolyte. While the anode materials are generally based on silicon, carbon and tin, the cathode materials include layered LiCoO2, spinel LiMn2O4, olivine LiFePO4, layered LiNi0,8Co0,15Al0,05O2(NCA) and layered LiNiCoMnO2 (NMC). Nmc and nca cathode materials stand out due to their high energy densities. Of course, lithium-ion batteries also have some disadvantages. A prime example of this is the capacity reductions it experiences with the increasing number of cycles. The main reasons for the decrease in capacity are; The transformation of the layered structure into spinel structure, the contamination of the Lio structure on the cathode to the electrolyte structure as a result of the side reactions that occur, damage the stable structure of the electrolyte and lead to Li loss. Metal oxide surface modification methods come to the fore in studies conducted to prevent these disadvantages. In this study, nmc structure was synthesized by reprecipitation method. Xrd, and sem analyzes of the obtained structure were taken. Al2O3 surface modification method was applied on the cathode surface. Cyclic voltammetry analyzes of the nmc structures with and without the modification applied were made with the help of potentiometry and the results were compared.
