فهرست مطالب

  • Volume:3 Issue: 1, Winter-Spring 2022
  • تاریخ انتشار: 1401/04/02
  • تعداد عناوین: 12
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  • T. Oyegoke *, E. Obadiah, Y. S. MOHAMMED, O. BAMIGBALA, O. A. OWOLABI, T. GEOFFREY, A. Oyegoke, A. Onadeji Pages 1-19
    Increasing energy demand and fossil fuel dependency have increased interest in bioethanol production in recent years. The use of conventional saccharine and starchy materials for ethanol production is prohibitive as it is a threat to food security. As such, rice husk poses to be of great value, providing a means to utilize waste. This study assessed the economic viability of bioethanol production from rice husk waste, which entails capital and manufacturing cost estimation, and profitability of this process. Further cost optimization studies were carried to determine the material cost, government subsidy, and tax potential to maximize the overall financial benefit (i.e., ROI and net profit) of the bioethanol production. Findings from this study indicated that transforming rice husk into bioethanol would not be economically feasible due to negative net profit (i.e., a loss on investment) obtained from its profitability analysis. Further studies indicated that the project was susceptible to the raw material cost, subsidy, and tax rate. Result obtained from the optimization studies indicates that if the rice husk sales as low as 1.38 US$/kg, and Government introduced 25% subsidy and tax-free policy on bioethanol production, the project would yield a net worth of US$ 5 million per annum, payback period of 5.5 years, and a return on investment of 16.1%. Therefore, this study recommends introducing a subsidy and tax-waiver policy for biofuels production to encourage investors and promote cleaner fuels in emerging nations.
    Keywords: Bioethanol, Biomass, Optimization, Economic, Biofuels
  • R. Alayi *, Syed R. Seydnouri, M. Jahangeri, A. Maarif Pages 21-30

    Given the decline of non-renewable energy sources, trying to find new technologies and ways to supply energy and reduce fuel consumption is one of the top priorities of the world. One of the new technologies is fuel cell technology, which has received very little attention in Iran so far, and there is a need to study this technology more and more carefully, especially in combination with renewable energy sources in order to help energy decision-makers. Therefore, in the present work, for the first time, a hybrid wind-solar-fuel cell system for residential use in Yazd, located in the hot and dry climate of Iran, has been simulated using HOMER software. The aim is to find an optimal economic system to supply 15 kWh of electricity per day and to assess the impact of uncertainties, sensitivity analysis was performed on the intensity of solar radiation and wind speed. The simulation results show that the most economical system consists of a fuel cell, is based on wind turbine and solar cell, and has a total NPC, LCOE and LCOH of $ 23,674, $ 0.824 per kilowatt-hour, and $ 254.4 per kilogram, respectively. Also, not using the battery will lead to a 33.6 percent increase in the cost per kilowatt-hour of electricity generated. For wind speeds of more than 8 meters per second, the results show that the optimal system with a fuel cell only includes wind turbines, and therefore increasing the intensity of solar radiation has no effect on the results.

    Keywords: Hybrid system, fuel cell, Off-grid, LCOE, LCOH
  • F. Salek, M. Rahnama, H. Eshghi, M. Babaie, M. M. Naserian * Pages 31-40
    In this study, a solar driven alkaline electrolyzer producer of hydroxy gas is proposed which is integrated with photovoltaic panels with single-axis north-south solar tracking system. The main novelty of this work is providing transient analysis of integration of alkaline electrolyzer to the PV panels equipped with solar tracking system. Furthermore, the transient model of the alkaline electrolyzer is employed to calculate its operating temperature, hydroxy production rate and the other operational parameters at various hours of the day. The electrolyzer and PV panels with tracking system are modelled in EES software. It is assumed that the system is installed in Shahrood city, therefore, the geographical data this city is used for seasonal analysis. The effective area of electrolyzer electrodes and PV panels is also assumed to be fixed at 0.25m2 and 50m2, respectively, in this study. Based on the results, employment of solar tracking system resulted in significant increment of PV panels power absorption rate resulting in power increment up to 4.2kW in summer. On the other hand, the transient analysis of the proposed alkaline electrolyzer showed that the maximum operating temperature of which reaches 80oC at around 12 AM in the summer cause of achieving maximum electrical current peak in summer. Therefore, an efficient cooling system should be employed in summer for decrement of alkaline electrolyzer temperature. The proposed system is capable of producing 7.6m3/day, 10.4m3/day, 7.2m3/day and 4.1m3/day hydroxy gas in spring, summer, fall, and winter, consecutively.
    Keywords: Alkaline electrolyzer, hydroxy gas, photovoltaic panel, Solar Tracker
  • P. Jagadale *, A. Choudhari, S. Jadhav Pages 41-49
    During past decades, increasing energy demand across the world fueled energy production significantly, which lead to environmental impacts such as Global warming, depletion of the ozone layer, it also endangered the Species. Hence, the whole world started shifting towards green energy generation, eliminating all the negative Impacts on the environment. Solar power is the most efficient source of energy among other renewable energy sources. This article analyzes the simulated performance of a 250 kWp grid-connected Si-poly photovoltaic Plant. This study was conducted to evaluate the performance and feasibility of a Solar PV plant for Pune, India Location. Each Module has a rating of 310 Wp are connected in 65 strings with 12 panels per string. 42 String Inverters are utilized. The simulation is carried out in PVsyst 7.2 software and Meteonorm8.0 data is used. The simulation is carried out to get maximum energy production, this experiment was performed in 2 phases, one with a fixed angle throughout the year and another by adjusting the tilt angle for every month. Multiple trials were conducted to get the best angle for maximum production of electricity. And compared their parameters such as incident radiation, Performance ratio, Energy into the grid, energy output at array and losses. The optimum angles were chosen based on input Energy at the grid.
    Keywords: Power, Renewable energy, Tilt angle, Energy generation
  • Sh.Sh. Dol *, A. Khamis, M. T. Abdallftah, M. Fares, S. Sh. Pervaiz Pages 51-59
    The current research illustrates the optimization of Vertical Axis Wind Turbine (VAWT) blades with implementation of added winglets displaying improved self-starting capabilities. The application of improved design is to be utilized in a university campus located in United Arab Emirates (UAE) in order to reduce its margin of consumed electrical energy by 15%. The study is conducted over a mean wind speed value of 5 m/s achieved in a one-year period at a specific altitude of 50 m in the UAE. Two aerodynamic simulation software were adopted, namely ANSYS FLUENT CFD and QBlade, with designs being modelled using AutoCAD. The analytical analysis included some aerodynamic characteristic such as power, lift, and drag coefficients. Through 2D-computational fluid dynamics (CFD), simulation study tested 20 different symmetrical as well as asymmetrical airfoils including the cambered S-0146 with 26.83% higher power output and lower noise amongst the test subjects. Turbine torque for added winglet design results in 4.1% higher compared to the benchmark. The modified design aims to produce at least 2% more power and have an improvement in self-starting of at least 20%. VAWTs tend to have higher potential and sensitivity towards wind direction (no yawing mechanism required) illustrating them as more cost-effective. Future scope includes utilizing wind lens technology to increase the free-stream velocity.
    Keywords: VAWT, Aerodynamics, Winglet, Self-starting
  • Sh. Mohammadi, A. Maleki *, R. Ehsani, O. Shakouri Pages 61-70
    The present study aims to investigate the possibility of using wind energy in some regions of Zanjan province. The current research concentrates on computing the wind energy potential and wind power density. Furthermore, some features related to wind for two locations in Zanjan province have been obtained. Feasibility study of wind energy utilization and computing of wind power density and wind power potential has been widely (Extensively-comprehensively) conducted for Zanjan province. First, two locations in Zanjan province have been considered to analyze the data at a reasonable level of province and to avoid over-focusing on one area. Thereafter, the statistics about wind speed were achieved from the Renewable Energy Organization of Iran in ten-minute intervals and included wind speeds at the heights of 30,10, and 40 m and wind directions at heights of 30 and 37.5 m. Finally, various wind features have been investigated for given locations in Zanjan province. The results demonstrate that the annual wind speed for Soltanieh and Tarom in the height of 40 m were 4.81 m/s and 3.93 m / s, respectively. The highest value U_me and U_mp is calculated, It was observed at a height of 40 m at Soltanie, It is 11.35 m / s and 1.27 m / s, respectively. Also, the performance of several wind turbines in the mentioned areas has been investigated. Finally, a suitable wind turbine has been identified.
    Keywords: Wind turbine, Wind energy potential, Power density, Weibull distribution
  • Z. Molamohamadi *, M.R. Talaei Pages 71-78
    This paper aims to analyze and identify the most appropriate strategies to deploy solar energy in Iran. For this purpose, in a comprehensive framework of strategy development, the internal and external factors of general and specific environment were determined. Then, four different strategies, including aggressive (strong expansion and development), conservative (maintaining, internal protection), competitive (maintaining, external protection), and defensive strategies (withdrawal, reduction of costs, ceasing on investment, joining another corporation), were considered using internal-external and SWOT (Strengths, Weaknesses, Opportunities, and Threats) matrices. According to the numerical results of the internal and external factor evaluations, which are 2.74 and 3.06 respectively, the aggressive strategies would be acceptable for Iran. However, since the location of these values in the internal-external matrix is close to the conservative cell, the effective strategy for the present condition of our country is a combination of aggressive and conservative strategies.
    Keywords: solar energy, sustainability, SWOT Analysis, PESTEL analysis, renewable energy policies
  • Sh. Momen, J. Nikoukar *, M. Gandomkar Pages 79-92
    Global warming and prices of energy carriers within political conflicts between different nations, are some of the problems for traditional energy production and economic dispatch. In traditional generation systems, about 25 percentage of energy is wasted, and the presence of Distributed Energy Resources (DERs) such as Photovoltaic, Wind Turbine and wind farms, Fuel Cell, and the Combined Heat and Power can reduce fuel consumption, pollution, transmission losses, and increase the microgrid productivity. In this paper, a complete energy management framework in a microgrid is proposed by considering the load distribution constraints using Improved Shuffled Frog Leaping Algorithm (ISFLA) algorithm, in which it determines the exact share of energy production or consumption for different units. The proposed scheme is used to select the best arrangement of DERs in the power grid, which the output of which is to determine the number and optimal location of DERs in the several bus-bars of the grid. Then, the Independent System Operator (ISO) determines the quantity of energy exchange and consumption by considering the load distribution constraints. Boilers and CHPs have also been used to maintain the balance between the production of thermal power by energy sources and thermal demands. In addition, the Demand Response Program has been used with the aim of smoothing the load curve and reducing the operating costs. Finally, the proposed method is implemented and simulated on the IEEE 69 and 118 bus systems using MATLAB, which comparing the output results with existing algorithms, shows the superiority of the proposed method.
    Keywords: Demand Response, Energy market, Optimization, Distributed Energy Resources, Improved Shuffled Frog Leaping Algorithm
  • M. Ahmadi, S.A.A. Mirjalily *, Seyed A. A. Oloomi Pages 93-102
    This study applies an appropriate turbulence model to simulate the wind distribution in a 3D urban area around a tall building as a bluff body which is one of the most important research topics due to the increasing concerns about human health risks due to air pollution in recent decades. Hybrid RANS/LES approach, was used to reduce computation time while maintaining computational accuracy. On the other hand, since no homogeneous direction exists in the flow in the Hybrid (RANS-LES) approach, the LES and Smagorinsky Sub Grid-Scale (SGS) approach are implemented with the standard k-ε turbulence model as RANS. To obtain more accurate results, the second-order Van Leer Method (VLM) was employed in advection terms. The sensitivity study of the input parameters shows that the intensity of the input turbulence has a significant effect on the surface pressure fluctuations. The results of velocity and pressure distribution showed a very close agreement to wind tunnel experimental data. Finally, the effects of the inflow characteristics on the peak pressure on the lateral sides is also studied. As the results, fluctuation pressure distribution was strongly dependent on the turbulence of the flow.
    Keywords: Hybrid RANS-LES approach, Wind Distribution, Tall Building, Bluff Body, Pressure Distribution
  • A.R. Shateri, I. Pishkar *, Sh. Mohammad Beigi Pages 103-114
    Trombe walls and solar chimneys have been widely used by the construction industry for many years to heat buildings. In this study, the heat conductance of a Trombe wall was simulated and studied. The equations related to energy and momentum were solved numerically by use of the technique of control volume. The equations were solved simultaneously using the Simple algorithm. At first, a base case was defined and simulated. A sensitivity analysis study was then performed to investigate the parameters affecting the performance of the wall. Based on the results, an optimized geometry was suggested which maximized the performance of the Trombe wall. In addition, the effect of the presence of the fins on the surface of the absorber wall was studied. In order to obtain the best geometry, the fins were assumed to have different shapes but a constant area. The results showed that the Trombe wall with rectangular fins demonstrated the best performance compared to the other fin geometries studied in this paper. The presence of rectangular fins can increase the room temperature by 1.24% compared to other fin geometries.
    Keywords: Optimization, Trombe wall, Solar Chimney, Numerical Simulation, Fin
  • M. Mohamadi Janaki, M. A. Sobhanallahi *, A.R. Arshadi Khamseh Pages 115-129
    The trend of the fourth industrial revolution in the field of energy, like other sectors, indicates that the path of production, development and approaches to energy use in the world is changing every day. This change can be seen in the growth of new energy production in developed countries by renewable energy. Owing to the global energy crisis all around the world and the exhaustible non-renewable energy resources, as well as increasing the pollution and green supply chain due to the indiscriminate use of fossil fuels, the need to use sustainable energy, especially In the industrial sector, which accounts for 40% of energy consumption in our country, has been paid attention to. The present study developed and prioritized green supply chain strategies with uncertainty over time under fuzzy conditions in Mobarakeh Steel Company. First, the internal strengths, weaknesses, opportunities, and threats were identified based on theoretical foundations and experts’ opinion. Then, the green supply chain strategies of Mobarakeh Steel Company were developed using the SWOT method. Fuzzy ANP method was used for weighing the dimensions of sustainability while the TOPSIS and TODIM methods were used for weighing the strategies. The results indicated that among the indicators of sustainability, "social" indicator had the first rank, "environmental" indicator had the second rank, and "economic" indicator had the third rank. In addition, SO strategies had the first rank, ST strategies had the second rank, WO strategies had the third rank, WT strategies had the fourth rank.
    Keywords: Green Supply Chain Strategies, Renewable energies, Fuzzy Conditions, Mobarakeh Steel Company
  • A.H. Bolurian, H.R. Akbari *, T. Daemi, S.A.A. Mirjalily, S. Mousavi Pages 131-141
    This paper proposes an integrated energy management system for grid-connected microgrids, taking into account the demand response programs, fossil fuel-based generators, renewable energy sources and energy storage systems. In the proposed approach, the constraints of the problem are considered jointly in the model of the energy management systems and are used for microgrid energy management planning and economic dispatch. One of the innovations of this paper is to use the Internet of Things (IoT) platform to adjust the maximum ramp rate of production units in microgrid due to the limitations of production capacity. Since the system considered, models the general state of the internet communication of objects without the need to access the communication channel, so that the energy of consumers should be minimized as second objective function.in this platform, whenever one of the objects has a message to send, it sends it without the need to reserve a resource and schedule. The IoT can establish a good relationship between power producers in a way that reduces operating costs by exchanging data. Optimization of energy consumption in the hybrid power grid studied in this paper shows that the use of IoT platform can reduce the transmission line losses in addition to operating costs. The output results of using data in the IoT context and comparing it with the traditional mode represent the superiority of the proposed approach.
    Keywords: Internet of Things (IoT), Energy Management, Optimization, Smart grid