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Öğe A comprehensive assessment of energy storage options for green hydrogen(Pergamon-Elsevier Science Ltd, 2023) Karayel, G. Kubilay; Javani, Nader; Dincer, IbrahimThe current study investigates suitable hydrogen storage technologies for hydrogen produced by renewable energy resources in a green manner. Type-I, III, and IV high-pressure tanks, adsorbent storage, metal hydride storage and chemical storage options are investigated and compared based on their hydrogen storage capacities, costs, masses and greenhouse gas (GHG) emissions. The results of this study show that in a Type-IV hydrogen storage tank (i.e., composite material tank of carbon fiber with thermoplastic polymer liners), increasing the tank pressure from 100 bar to 800 bar increases the hydrogen holding capacity by 457.7%. Regarding the environmental impact, the lowest GHG emissions appear to be the lowest for liquid hydrogen storage with an average of 3.5 CO2eq/kg-H2 while the respective emissions become the highest in metal hydride storage tanks as 113.6 CO2eq/kg-H2. Furthermore, hydrogen storage capacity for Type-IV tanks varies from 1.94 kg at 100 bar to 15.69 kg at 1500 bar in a 250 L tank. In chemical hydride storage tanks, the stored H2 mass will be 40.75 kg for 100 L, 128.39 kg for 200 L, 216.03 kg for 300 L, 303.67 kg for 400 L, 391.31 kg for 500 L and 478.96 kg for 600 L, respectively. Moreover, hydrogen storage, distribution and dispensing are considered critically important in hydrogen logistics and the results of this study will help better guide policymakers to establish effective policies and increase renewable energy penetration in the energy market.Öğe Design and optimization of a novel wind-powered liquefied air energy storage system integrated with a supercritical carbon dioxide cycle(WILEY, 2021) Sadeghi, Shayan; Javani, Nader; Ghandehariun, Samane; Ahmadi, PouriaIn this paper, a novel liquefied air energy storage (LAES) system driven by wind energy and natural gas, integrated with a two-stage supercritical carbon dioxide cycle is proposed and investigated. Three different sensible thermal energy storage (TES) systems are considered in this study to store the heat produced in the compressions stage and use it later to improve the performance. The proposed system is analyzed in terms of energy, exergy, exergo-economic, and environmental impacts. A detailed economical and technical investigation is carried out to determine system hotspots, exergy destruction rates, and the performance of the system and subsystems. Finally, by considering ten design variables, the nondominated sorting genetic algorithm-II (NSGA-II) is employed to evaluate the optimal design solutions for double objective functions, including cost per unit of exergy and overall system exergy efficiency. Results indicate that for a 50 MW of discharging power, 80.75 MW of charging electricity and 1.22 kg/s of fuel are required. Additionally, the product cost per unit of exergy and the levelized costs are calculated as 32.02 $/GJ and 0.133 $/kWh, respectively. The results of the optimization study also show that for the optimal Pareto solution, the energy efficiency would be 52.2% while the exergy efficiency is 45.26%.Öğe Effective use of geothermal energy for hydrogen production: A comprehensive application(Elsevier Ltd, 2022) Karayel, Görkem Kubilay; Javani, Nader; Dinçer, İbrahimThe present study aims to investigate the geothermal energy potential for green hydrogen production in Turkey. Geothermal energy potential varies based on each city's location and underground resources (particularly on their flowrates, temperatures and composotion). Alkaline electrolysers (ALELs) are considered for water splitting and hence hydrogen production. The total hydrogen production potential for Turkey using geothermal resources is estimated to be 559.76 kilotons. In this regard, Aydın, Manisa, and Denizli appear to be the cities with the largest hydrogen production potentials. Hydrogen generation potentials for all Turkish cities are provided and discussed for a feasible hydrogen economy. It furthermore gives a countrywide spectrum of how an effective role geothermal energy can play in making the country leader in this field. The study results may serve as a good base for planning and strategizing purposes as required for the country and help in developing new energy policies for exploiting renewable energy resources. © 2022 Elsevier LtdÖğe Hydrogen farm concept: a perspective for Turkey(WILEY, 2021) Dinçer, İbrahim; Javani, Nader; Karayel, Görkem KubilayPERSPECTIVEHydrogen farm concept: A Perspective for Turkey1 | INTRODUCTIONClimate change mitigation and implementing the neces-sary rules and regulations are terribly needed to makethe global commitment stronger than ever before. On theenergy side which is closely linked to these, energy mar-ket is and will be more struggling to afford turning awayfrom fossil fuels and move into decarbonization era.Since the industrial revolution, a drastic increase inthe anthropogenic carbon dioxide concentrations inthe atmosphere has bee n observed and affected thehuman health and human welfare, and such anthropo-logical effects cannot be gainsaid, despite a ll political-based denials and traditional fossils fuels lobbies'enforcements.Öğe Hydropower energy for green hydrogen production in Turkey(Elsevier Ltd, 2022) Karayel, Görkem Kubilay; Javani, Nader; Dinçer, İbrahimThe current study develops a hydro-based hydrogen production concept and investigates the utilization of hydroelectric power for green hydrogen production in Turkey. For the hydroelectric power potential calculations, the installed and under construction hydroelectric power plants, run-of-river systems, and reservoir dams are considered for the entire country. The potential capacities of each city are estimated based on the available official and published data by the government agencies, and some reasonable assumptions are also made for detailed analysis and assessment for a feasible hydrogen economy in the country. The results obtained here clearly show that the contribution of hydroelectric energy to hydrogen production is considerable high in promoting countries towards leadership in the field of green hydrogen production. Based on the analysis results, Turkey's hydro-based green hydrogen production potential is estimated to be 2.26 megatons. Şanlıurfa, Elazığ, Diyarbakır, Artvin, and Adana are cities with the highest green hydrogen production potential from hydroelectric power with an annual production capacity of 233.09, 204.92, 175.35, 157.28, and 140.8 kilotons, respectively. The results of this study are expected to help the policymakers to use hydropower energy for planning and developing action plan for the country and help overcome carbon-based fuel usage and its associated pollution. The main idea is to prepare hydrogen maps in detail for each region in Turkey, based on the hydro energy potential by using electrolysers. This, in turn, can be considered in the context of the current policies of the local communities and policymakers to prepare a sustainable energy roadmap for the country. © 2022 Hydrogen Energy Publications LLCÖğe Sustainable city concept based on green hydrogen energy(Elsevier Ltd, 2022) Dinçer, İbrahim; Javani, Nader; Karayel, Görkem KubilayThe current study investigates the green hydrogen production from renewable energy sources for the metropolitan city of Istanbul by using electrolysers. The main idea is to create a hydrogen map for every district in Istanbul, based on renewable energy sources and water splitting technology. The potentially available renewable sources, such as solar (including offshore), wind (including offshore), biomass, geothermal and underwater current are used for calculating the total hydrogen production potential. Istanbul's potential for producing green hydrogen is estimated to be 7.96 Mt. The study results show that Catalca, Şile, Silivri, Arnavutköy, and Beykoz come out as the districts with the highest green hydrogen potential with 1.49 Mt, 1.19 Mt, 1.12 Mt, 0.57 Mt, and 0.46 Mt, respectively. After supplying the necessary power demand for the city, the remaining power is used to produce green hydrogen which may contribute an economic value of over US $100 billion with a current price of $13/kg of hydrogen and 23.88 billion US$ with a targeted price of $3/kg of hydrogen, respectively. The available potentials for each district are also specifically studied and discussed. It is more importantly expected to reduce the greenhouse gas emissions by about 90% which will ve very important to achieve a carbon-neutral city and hence country due its dominated role. Furthermore, the results provide a clear guidance to enable policymakers and private sectors to use renewable energy potentials for their investment purposes or promote clean energy programs, tackling carbon-based energy consumption, pollution, and greenhouse effect. This, later on, can be used by policymakers and energy providers to help the city and local communities for achieving the United Nation's sustainable development goals.Öğe Sustainable marina concept with green hydrogen utilization: a case study(Elsevier, 2022) Karayel, Görkem Kubilay; Javani, Nader; Dinçer, İbrahimThe current study investigates the green hydrogen production from renewable energy for a sustainable yacht marina. The main idea is to create a sustainable harbor for utilizing renewable energy sources using electrolysers to produce hydrogen and providing power for both marina energy demand and transportation fuel needs. Generating electricity from renewable energy resources and converting into green hydrogen in marinas are the main objectives of the current study. Solar and wave energy resources are used for calculating total hydrogen production potential. Four different sizes of luxury yachts are considered in the calculations. The considered three yacht marinas are located in Malaga, Mugla, and Istanbul. The average annual green hydrogen production potential of a marina from offshore solar energy is estimated to be 1.34, 1.38, 1.47 kt, and annual green hydrogen production from wave energy is 2.66, 3.06, 3.99 kt for the considered marinas locates in Marbella, Bodrum, and Atakoy, respectively. During the summer season, 400 small-sized, 250 medium-sized, or 100 large-sized yachts are potentially considered for fueling with green hydrogen. At maximum capacity, in Atakoy marina, which is chosen for the case study, a total of 243 hydrogen-fueled mega-yachts can potentially be refueled with green hydrogen. The study results show that the marinas selected in the specified locations appear to feasible for sustainable hydrogen applications. © 2022 Elsevier LtdÖğe Utilization of biomass and waste resources for renewable hydrogen production: A comprehensive study(Taylor & Francis Inc, 2023) Karayel, G. Kubilay; Javani, Nader; Dincer, IbrahimThe current study investigates the biomass and waste-based potential for green hydrogen production in Turkey. The biomass sources are identified based on the collection of municipal, industrial, animal, agricultural, and forestry wastes. The potential of each city is estimated and discussed for a feasible hydrogen economy. Using the legitimate government data obtained from the governmental sources, the capacities of the available biomass potential for different cities in tons of oil equivalent are considered annually for the analysis and assessment. The power production is considered through using gasification and incineration systems, where the final product is hydrogen. The main idea is to prepare hydrogen maps in detail for each region in Turkey, based on the biomass energy potential through employing the gasification and incineration approaches. The results show that Turkey's total green hydrogen production potential using available biomass resources is about 1.66 megatons/year. Konya, Adana, Ankara, Sanliurfa, and Manisa are listed as cities with the highest green hydrogen production potential with an annual production of 129.53, 78.82, 64.42, 64.2, and 53.63 kilotons, respectively. The results of the study are expected to help policymakers to use renewable energies for planning and strategizing new local and global acts for the country and help to tackle fossil-fuel-based issues. This, in turn, can be considered in the context of the current policies of the local communities to supply the required energy.
