Renewable Energy Resources and Technologies
Hediyeh Safari; Fateme Ahmadi Boyaghchi
Abstract
This research is concerned with the design and analysis of a geothermal based multi-generation system by applying both conventional and advanced exergy and exergoeconomic concepts. The proposed energy system consists of a dual-organic Rankine cycle (ORC) to vaporize liquefied natural gas (LNG) and produce ...
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This research is concerned with the design and analysis of a geothermal based multi-generation system by applying both conventional and advanced exergy and exergoeconomic concepts. The proposed energy system consists of a dual-organic Rankine cycle (ORC) to vaporize liquefied natural gas (LNG) and produce electricity. A proton exchange membrane(PEM) electrolyzer is employed to produce hydrogen by receiving the power and coolant heat waste of dual ORC. Moreover, cooling effect is produced during LNG regasification by utilizing the cryogenic energy of LNG. Parametric studies are conducted to assess the effects of substantial input parameters, namely turbine 1 inlet pressure, mass rate of upper cycle, geothermal mass flow rate, on the various parts of exergy destruction and cost rates within the major components.
Renewable Energy Resources and Technologies
Ali Mostafaeipour; Mohammad Saidi Mehrabad; Mojtaba Qolipour; Mohadese Basirati; Mostafa Rezaei; Amir Mohammad Golmohammadi
Abstract
The present study aimed at ranking and selecting the superior geothermal project for hydrogen production in 14 provinces of Iran using a multi-objective optimization fuzzy hybrid approach through analyzing the ratio (fuzzy Moora) and expanded entropy weighting method. In this research, the extended entropy ...
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The present study aimed at ranking and selecting the superior geothermal project for hydrogen production in 14 provinces of Iran using a multi-objective optimization fuzzy hybrid approach through analyzing the ratio (fuzzy Moora) and expanded entropy weighting method. In this research, the extended entropy weighing method and the Fuzzy-Moora approach were utilized to weigh the criteria and project the ranking, respectively. In this research, 13 criteria for ranking the geothermal projects in Iran have been selected for hydrogen production. At first, the technical-economic feasibility of the projects was carried out in Homer software, and then the ranking process was performed with the proposed hybrid approach. The results showed that among 14 studied provinces using geothermal energy, the provinces of Bushehr, Hormozgan, Isfahan, Mazandaran, East Azarbaijan, Fars, Qazvin, Zanjan, Ardebil, Khorasan Razavi, Kerman, Sistan and Baluchestan, South Khorasan and West Azarbaijan were ranked in that order in terms of hydrogen production.
Mehdi Jamali Ghahderijani; Fathollah Ommi
Abstract
In this paper, a solar based hydrogen production in the city of Tehran, the capital of Iran is simulated and the cost of produced hydrogen is evaluated. Local solar power profile is obtained using TRNSYS software for a typical parking station in Tehran. The generated electricity is used to supply power ...
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In this paper, a solar based hydrogen production in the city of Tehran, the capital of Iran is simulated and the cost of produced hydrogen is evaluated. Local solar power profile is obtained using TRNSYS software for a typical parking station in Tehran. The generated electricity is used to supply power to a Proton Exchange Membrane (PEM) electrolyzer for hydrogen production. Dynamic nature of solar power and necessity of reasonable accuracy for estimating of amount of hydrogen production leads to propose a new 1D dynamic fluid flow model for PEM electrolyzer cell simulation. The hydrogen price in this system is estimated using Equivalent Annual Worth (EAW) analysis. Although it is convenient to select a yearly useful lifetime for electrolyzer as well as solar cells in this paper an hourly lifetime is considered which allows finding the hydrogen cost based on electrolyzer operating time. Also, electrolyzer sizing is done by selecting various number of cells for each stack and alternatives are compared from performance and economic point of view. In this regards 4 cases consist of 2, 3, 4 and 5 electrolyzer cell are compared. Hydrogen price at each case is evaluated and sensitivity analysis is performed. The results represent that the system with higher efficiency is not always an economical choice. As an alternative, the electrolyzer turning off at some conditions is also investigated for possibility of extending lifetime and reducing the hydrogen price. It is found that turning off the electrolyzer under specified minimum current density (2000 A/m2) in all cases reduce the final produced hydrogen price however this price and electrolyzer size is still strongly dependent to the electrolyzer capital cost.