WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
Browse
5 results
Search Results
Now showing 1 - 5 of 5
Article Geothermal Drying in Agricultural Sector - Worldwide Examples(Elsevier Ltd, 2026) Tomaszewska, B.; Baba, A.; Akkurt, G.G.; Mukti, M.; Helvaci, H.U.; Bielec, B.; Operacz, A.Agricultural drying is traditionally used to preserve fruits and vegetables which mostly relied on energy-intensive processes usually powered by fossil fuels. In this review, we explore an innovative and sustainable alternative: using geothermal energy to dry produce. The paper reviews the main technical aspects related to the use of geothermal energy in drying fruits and vegetables. We delve into the technical details of two leading methods, hot air drying and refractive window drying, highlighting their advantages, drawbacks, and the critical factors that influence the quality of the final product. By examining real-world applications from countries as diverse as Iceland, the USA, Greece, Turkey, Macedonia, Kenya, Serbia, El Salvador, Guatemala, Mexico, Thailand, Poland, and the Philippines, this paper showcases how geothermal energy can be directly applied in drying operations—whether through standalone systems operating between 60 °C and 97 °C or integrated cascade systems wherever geothermal resources are used for power generation and in the form of the waste heat for drying purposes, can be considered as important direction. Due to a lack of actual information on the economic aspects of geothermal drying, in addition to outlining the technical merits of geothermal drying, we also discuss economic considerations and potential challenges to provide a roadmap for future projects. Moreover, the authors underlined several aspects that can contribute to the failure or limited success of geothermal drying projects. Ultimately, adopting geothermal drying not only reduces greenhouse gases (GHS) emissions but also lessens dependence on costly, polluting fossil fuels, paving the way for a greener, more energy-efficient future in food preservation. © 2025 Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.Article Floating Pontoons to Reduce Wave Overtopping at a Vertical Seawall: An Experimental Study(Elsevier Ltd, 2026) Eroglu, N.; Ozbahceci, B.Coastal flooding caused by extreme wind, wave and water level conditions is an increasing concern, particularly for historical coastal cities where conventional flood defenses may be unsuitable due to aesthetic and cultural constraints. Floating structures have gained attention for their adaptability to sea level rise, yet previous studies have mainly examined wave transmission rather than their capacity to reduce wave overtopping. This study presents the first experimental investigation to directly measure wave overtopping for floating pontoons placed in front of a vertical seawall. Tests were conducted in a controlled wave flume environment to evaluate the effects of pontoon geometry, mooring type, and distance from the seawall on overtopping performance. The results show that floating pontoons can significantly reduce wave overtopping. Overtopping reductions of 75–98 % was achieved, with the most effective configuration combining high freeboard and large draft (1.5 m prototype scale). Wave transmission was also measured and compared with existing prediction formulas. When the transmitted wave height is used in EurOtop (2018) formula, overtopping rate is overestimated particularly when the relative crest freeboard exceeds 0.75 as differences in wave steepness, spectral period and directional spreading induced by the floating pontoon are not captured by the formula. To improve predictive capability, a new influence coefficient (γ<inf>fp</inf>) is proposed to modify Eq. 7.5 in EurOtop (2018) for cases involving pile-guided floating pontoons. These findings provide new experimental evidence on wave–structure interaction and highlight the potential of floating pontoons as effective, adaptable, and visually compatible flood mitigation solutions for vulnerable coastal regions. © 2025 Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.Article Citation - WoS: 21Citation - Scopus: 23Lithium: an Energy Transition Element, Its Role in the Future Energy Demand and Carbon Emissions Mitigation Strategy(Elsevier Ltd, 2024) Chandrasekharam,D.; Şener,M.F.; Recepoğlu,Y.K.; Isık,T.; Demir,M.M.; Baba,A.Energy transition elements (Li, Ni, Co, Fe, Cu) are gaining importance due to their ability to provide energy and play an important role as primary energy sources. Because of the energy density and power density, Li-ion batteries have the edge over other batteries. Li is distributed in various rock-forming minerals and brines, and geothermal waters. Though lithium-bearing minerals are spread over a broad geographic region, these minerals are confined to certain countries with substantial economic potential. Li is extensively used in batteries, and battery-driven vehicles are growing exponentially to meet the carbon reduction goal of the Paris agreement in 2015 and signed by more than 50 percent of the countries. Nearly 55 million cars supported by Li batteries are expected to roll out by 2030. While this is the demand, its occurrence and concentration/extraction processes are not keeping pace with this demand. The extraction of Li from its ore is an energy-intensive process involving many fossil fuel-based energies. To recover one ton of Li metal, nearly 5 to 6 tons of CO2 is emitted. The CO2 emissions of 28 kWh LFP, NMC, and LMO batteries vary from 5600 to 2705 kg CO2-eq. The end-of-life emissions of an internal combustion engine (ICE) vehicle are 400 kg CO2/vehicle, while Li Battery supports 500 kg/vehicle. The quantity of Li required for a 24 kWh average capacity leaf battery is about 137 g/kWh. While emissions are associated with the manufacturing of the batteries, emissions are also associated with a way that while they are recharged as the recharging source is fossil fuel-based energy. The best option to meet zero net carbon emissions by 2050, as envisaged by International Energy Agency (IEA), is to recover Li from geothermal brines and use geothermal energy for recharging. While hydrothermal energy sources are site-specific, enhanced geothermal system (EGS) based geothermal energy is not site-specific and is found wherever high radiogenic granites are available. High radiogenic granites are widely distributed, and heat recovered from EGS sources can provide clean energy and heat. Extraction of lithium from geothermal waters and using geothermal energy for recharging the batteries will drastically reduce CO2 emissions. It will drive the world towards Net Zero Emissions (NZE) scenario in the future. This is being practiced in Turkey. Future research should develop technology to recover Li from geothermal fluids with low concentration and support EGS development. © 2024 Elsevier LtdArticle Citation - WoS: 12Citation - Scopus: 12Enhancing a Bio-Waste Driven Polygeneration System Through Artificial Neural Networks and Multi-Objective Genetic Algorithm: Assessment and Optimization(Elsevier Ltd, 2024) Hajimohammadi Tabriz,Z.; Taheri,M.H.; Khani,L.; Çağlar,B.; Mohammadpourfard,M.This paper aims to study the feasibility of municipal sewage sludge utilization as an energy source in a polygeneration system. This system offers distinctive benefits such as contribution to the principled removal of sewage sludge, simultaneous utilization of raw and digested sludge in different parts of the system, and production of renewable hydrogen from bio-waste. 4E (energy, exergy, exergoeconomic, and environmental) analyses, are performed to understand the system performance comprehensively. Then, parametric studies are examined the impact of changing the values of main parameters on the system operation. Afterward, a multi-objective optimization based on a genetic algorithm is carried out to achieve optimal values, considering a trade-off between the exergy efficiency and the total cost rate. Meanwhile, this work harnesses the potential of artificial neural networks to expedite complex and time-consuming optimization processes. According to the results, the gasifier exhibits the highest rate of exergy destruction, and the primary cost of consumption is attributed to its heat supply. The multi-objective optimization findings show that the optimum point has an exergy efficiency of 38.26 % and a total cost rate of 58.17 M$/year. The hydrogen production rate, energy efficiency, and net power generation rate for the optimal case are determined as 1692 kg/h, 35.24 %, and 4269 kW, respectively. Also, the unit cost of hydrogen in the optimal case is obtained 1.49 $/kg which offers a cost-effective solution for hydrogen production. © 2024 Hydrogen Energy Publications LLCArticle Citation - WoS: 9Citation - Scopus: 8Enhanced Performance and Cycling Behavior in Symmetric Supercapacitors Developed by Pure Hfb2 and Hfb2-Sic Composites(Elsevier Ltd, 2024) Paksoy,A.; Yıldırım,İ.D.; Arabi,S.; Güngör,A.; Erdem,E.; Balcı-Çağıran,Ö.Boron-based materials have attracted growing interest as promising candidates for energy storage applications. This study focuses on synthesizing pure HfB2 powders through a straightforward method involving the mechanical activation of a powder mixture comprising hafnium tetrachloride (HfCl4), boron (B), and magnesium (Mg). The HfB2 powders were mechanically alloyed with varying amounts of SiC powders to create HfB2-based composite structures. The chemical and microstructural properties of the synthesized samples were assessed using XRD, SEM/EDX, and DLS characterization techniques. Supercapacitor device performances of all resulting powders as symmetrical electrodes were systematically investigated. The test results revealed that the pure HfB2 electrode material exhibited a pseudocapacitor behavior, whereas composite powders exhibited battery-like behavior. Composite powders, demonstrated enhanced supercapacitor performance surpassing that of pure powder in terms of energy density and cycle efficiency. The pure HfB2 electrode displayed the highest power density (95 Wkg−1) among all samples: Its distinctive pseudocapacitor behavior results in the highest power density, providing valuable insights into the intricate relationship between composition and electrochemical performance in boron-based supercapacitor materials. Moreover, these results propose that by synthesizing composite powders, the charge storage mechanism can be altered and used to improve the energy density. © 2024 Elsevier B.V.