Renewable Energy Resources and Technologies
Rasoul Aydram; Hossein Haji Agha Alizade; Majid Rasouli; Behdad Shadidi
Abstract
Reduced emissions of greenhouse gases and global warming can be made possible by discovering alternative energies and reduced dependence on fossil fuels. Biogas is considered as one of the alternatives to fossil fuels. This study investigates anaerobic co-digestion for the development of biogas with ...
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Reduced emissions of greenhouse gases and global warming can be made possible by discovering alternative energies and reduced dependence on fossil fuels. Biogas is considered as one of the alternatives to fossil fuels. This study investigates anaerobic co-digestion for the development of biogas with sheep blood and cheese whey. Digested cow manure was used as inoculum. Using the Design Expert 10 program and within the context of mixture design, the experiments were designed. Then, 22 experimental digesters with a volume of 500 mL were considered for doing the experiments considering the design output provided by the software. Each one was filled with 300 mL of different compositions of three matters. The digesters were kept in the mesophilic temperature range (37 °C ) for 21 days. Biogas was measured using the BMP test on a daily basis. According to the experimental findings, the best composition included 35 % sheep blood, 35 % cheese whey, and 30 % inoculum. This biogas composition produced a biogas yield of 146.66 mL/g vs. The amount of methane production in this compound was 73.33 mL/g vs. After modeling, the Design Expert software predicted an optimal composition including 44 % sheep blood, 24 % cheese whey, and 32 % inoculum. Biogas yield of this prediction was 143 mL/g vs. The findings show that in order to overcome acidification in digestion of matters such as cheese whey, a composition of matters with higher pH stability can be used to increase the amount of biogas and methane produced in a particular period. Furthermore, using inoculum accelerates the digestion operations due to existence of many microorganisms and saves time and energy.
Renewable Energy Resources and Technologies
Ahmad Naderi Nobandegani; Mohammad Ahmadzadehtalatapeh
Abstract
In the present study, the performance of a Desiccant Evaporative Cooling System (DECS) under eight different designs to provide the desired indoor air conditions for administration buildings was explored via TRNSYS software. An administration building in Chabahar, Iran as a region with a high cooling ...
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In the present study, the performance of a Desiccant Evaporative Cooling System (DECS) under eight different designs to provide the desired indoor air conditions for administration buildings was explored via TRNSYS software. An administration building in Chabahar, Iran as a region with a high cooling load demand was considered for the study. The simulation results indicated that the two-stage desiccant cooling system (Des. H) was the most suitable design, and it enjoyed the potential to keep the indoor air conditions within the standard recommendations. It was also shown that Des. H is the superior design in terms of energy performance and can meet the space cooling load requirements. The study showed that Des. H had the highest COP value with 2.83. The possible application of solar energy to the regeneration process of the Des. H was also studied. The simulations revealed that Des. H with and without the solar panels had less energy consumption than the existing system. The study showed that the application of Des. H could ensure 26.97 % saving in power per year in comparison to the existing system. Moreover, it was demonstrated that the addition of PVT panels to Des. H could increase the rate of annual power saving to about 68.03 %.
Environmental Impacts and Sustainability
Abotaleb Bay; Payam Ghorbannezhad; Javad Yazdan Moghadam; Rahim Aali
Abstract
The wastewater treatment of Medium Density Fiberboard (MDF) is a harsh process because of its contents of high suspended solids, chemical oxygen demand, high molecular weight of lignin, and fatty acids. Electrocoagulation (EC) process was used for efficient removal of pollutants and reusing the water. ...
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The wastewater treatment of Medium Density Fiberboard (MDF) is a harsh process because of its contents of high suspended solids, chemical oxygen demand, high molecular weight of lignin, and fatty acids. Electrocoagulation (EC) process was used for efficient removal of pollutants and reusing the water. The impact of aluminum and iron as sacrificial anodes on removal of Chemical Oxygen Demand (COD), Total Suspended Solid (TSS), turbidity, and Total Solid (TS) were investigated. A full quadratic model was deployed to optimize the EC process variables for pretreatment of MDF effluent through response surface methodology. The model results confirmed that the COD and TSS removal efficiency was enhanced upon increasing voltage and residence time; hence, other pollutants initially increased and then, decreased at higher levels. The comparison between aluminum and iron electrodes indicated that the polluted removal efficiencies of aluminum were higher than the iron electrode for MDF wastewater. The optimum values of voltage and residence time for electrocoagulation of MDF wastewater with aluminum were 33 V and 25 min, which resulted in 93 %, 89 %, 67 %, and 76 % for COD, TSS, turbidity, and TS removal, respectively. The implementation of electrocoagulation provided a possibility for reusing water and reducing water consumption in the MDF manufacturing process.
Environmental Impacts and Sustainability
Amir shasavari; Azadeh Karimi; Morteza Akbari; Mohammad Alizadeh Noughani
Abstract
Rising energy production and consumption, particularly from fossil fuels, pose substantial threats to both global climate and human well-being. Conventional fossil fuel technologies, as primary energy sources in power plants, predominantly generate pollutants during power generation. Conversely, renewable ...
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Rising energy production and consumption, particularly from fossil fuels, pose substantial threats to both global climate and human well-being. Conventional fossil fuel technologies, as primary energy sources in power plants, predominantly generate pollutants during power generation. Conversely, renewable energy technologies are anticipated to contribute to pollution primarily during equipment manufacturing. The combustion of traditional fuels gives rise to significant volumes of greenhouse gases (GHGs) and hazardous substances, leading to escalated costs for individuals and the worldwide populace. External costs attributed to coal-fired power plants range from 4.0 to 9.5 cents per kilowatt-hour, nearly three times higher than those of gas-fired power plants, and multiple times greater than the expenditures linked with renewable energy technologies. The substitution of non-renewable fuels with clean energy sources stands as an efficacious approach to curtailing atmospheric pollution and the concomitant external expenses. On a global scale, an annual savings of up to 230 billion dollars is potentially attainable by achieving a 36% share of clean energy within the global energy mix by 2030. This topic has garnered the attention of policymakers worldwide. Consequently, this study undertakes an examination of the environmental ramifications and social costs associated with diverse energy sources.
Renewable Energy Resources and Technologies
Ramasamy Dhivagar; Murugesan Mohanraj
Abstract
In this experimental work, the energy efficiency and performance parameters of a coarse aggregate-assisted single-slope solar still were analyzed using Taguchi analysis. The preheated inlet saline water was sent to the solar still using thermal energy accumulated in coarse aggregate to enhance its productivity ...
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In this experimental work, the energy efficiency and performance parameters of a coarse aggregate-assisted single-slope solar still were analyzed using Taguchi analysis. The preheated inlet saline water was sent to the solar still using thermal energy accumulated in coarse aggregate to enhance its productivity and energy efficiency. The daily distillate of the proposed model was observed to be about 4.21 kg/m2 with the improved efficiency of around 32 %. Furthermore, the parameters that influenced the performance of the solar stills and their levels were identified using Taguchi analysis. The Signal to Noise (S/N) ratios of the coarse aggregate temperature, saline water temperature, glass temperature and energy efficiency were observed to be about 45.4 °C, 41.4 °C, 36.7 °C and 20.07 %, respectively. The results revealed that, the percentage difference between predicted and experimental values was observed to be about 1.6 %, 0.6 %, 1.5 % and 3.3 %, respectively. The optimization method confirmed that there was good agreement between the predicted and experimental values.
Renewable Energy Resources and Technologies
Sajad Saberi; Behrooz Rezaie
Abstract
This paper presents a sensorless speed control algorithm based on Finite Control Set Model Predictive Control (FCS-MPC) for Permanent Magnet Synchronous Motor (PMSM) fed by a 3-level Neutral-Point Clamped (NPC) converter. The proposed scheme uses an anti-windup Proportional-Integral (PI) controller concept ...
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This paper presents a sensorless speed control algorithm based on Finite Control Set Model Predictive Control (FCS-MPC) for Permanent Magnet Synchronous Motor (PMSM) fed by a 3-level Neutral-Point Clamped (NPC) converter. The proposed scheme uses an anti-windup Proportional-Integral (PI) controller concept to generate the reference electromagnetic torque using the error of speed. Then, FCS-MPC uses this torque reference and other parameters such as a current limitation, neutral point voltage unbalance, and switching frequency to control the converter gate signals. Also, an Adaptive Nonsingular Fast Terminal Sliding Mode Observer (ANFTSMO) was employed to estimate rotor position precisely in positive (clockwise) and negative (counterclockwise) speed to eliminate the encoder. The proposed algorithm has fast dynamics and low steady-state error. Moreover, torque fluctuation and current distortion reduced compared with Space Vector Pulse Width Modulation (SVPWM) based speed control and Direct Predictive Speed Control (DPSC). Simulation results using MATLAB/SIMULINKÒ demonstrate the performance of the proposed scheme.
Renewable Energy Resources and Technologies
Marziyeh Gharibian; Bahram Hosseinzadeh Samani; Alireza Shirneshan; Sajad Rostami
Abstract
To investigate the possibility of using fuel for plant origin in a diesel generator, safflower methyl ester was prepared and used as a biodiesel. In this research, biodiesel was produced through a transesterification reaction using a hydrodynamic reactor, which increased the reaction efficiency and reduced ...
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To investigate the possibility of using fuel for plant origin in a diesel generator, safflower methyl ester was prepared and used as a biodiesel. In this research, biodiesel was produced through a transesterification reaction using a hydrodynamic reactor, which increased the reaction efficiency and reduced fuel production time. Upon increasing the reaction time from 30 seconds to 60 seconds, the reaction performance increased by 5.5 %. Then, its important features complied with ASTM D-6751 standard. The performance and pollution indices of the diesel generator engine were tested with compounds B0, B20, B50, B80 and B100. The results of short-term engine tests showed that by increasing the share of biodiesel to 20 %, CO emissions were reduced by 21 % compared to pure diesel fuel, but the amount of NOX increased by 0.82 % compared to diesel. Also, the use of 20 % volume of biodiesel in the fuel composition increased the thermal efficiency of braking, braking power, and braking torque of fuel, compared to diesel. Also, the specific fuel consumption of B20 was reduced by 2 %, which is very important economically. Finally, the TOPSIS analysis illustrated that B50 fuel outperformed pure diesel fuel and other listed fuel combinations.
Advanced Energy Technologies
Ghazanfar Shahgholian
Abstract
Renewable energy provides twenty percent of electricity generation worldwide. Hydroelectric power is the cheapest way to generate electricity today. It is a renewable source of energy and provides almost one-fifth of electricity in the world. Also, it generates electricity using a renewable natural resource ...
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Renewable energy provides twenty percent of electricity generation worldwide. Hydroelectric power is the cheapest way to generate electricity today. It is a renewable source of energy and provides almost one-fifth of electricity in the world. Also, it generates electricity using a renewable natural resource and accounting for six percent of worldwide energy supply or about fifteen percent of the world’s electricity. Hydropower is produced in more than 150 countries. Hydropower plant producers provide energy due to moving or falling water. This paper presents and discusses studies on hydroelectric power plant fields, which have been carried out by different investigators. This work aims to study and provide an overview of hydroelectric power plants such as applications, control, operation, modeling and environmental impacts. Also, the hybrid power and efficiency of the hydroelectric power plants has been investigated. The applications of a flexible AC transmission system (FACTS) controller in the power system with the hydroelectric power plants are presented.
Renewable Energy Resources and Technologies
Aychar Khajavipour; Mohammad Reza Shahraki; Faranak Hosseinzadeh Saljooghi
Abstract
The energy of processes is mainly supplied by fossil fuels. Short life of fossil energy sources and increasing environmental pollution caused by fossil fuels and increasing demand have made researchers introduce new solutions for supply of energy. Energy production in a photovoltaic solar power plant ...
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The energy of processes is mainly supplied by fossil fuels. Short life of fossil energy sources and increasing environmental pollution caused by fossil fuels and increasing demand have made researchers introduce new solutions for supply of energy. Energy production in a photovoltaic solar power plant is cost-effective due to being clean and renewable. The power generation of these plants is affected by their site due to climate conditions, effective radiation periods, and the rate of solar radiation absorption. Therefore, finding the optimal location to establish a solar power plant is important. Identifying effective location criteria and the importance of these criteria is effective in choosing the optimal location.In this research, in the first phase, the effective criteria in locating a photovoltaic solar power plant were investigated based on the Delphi method. Then, in the second phase, based on the criteria identified in the first phase, fuzzy hierarchy method was used to compare the criteria with each other and determine the importance of each of them. The results of the study showed that the rate of solar radiation and average temperature were the most important criteria in locating photovoltaic solar power plant. Moreover, the criteria of slope, distance to main roads, distance to power lines, and land use were of highest importance in locating a photovoltaic solar power plant.
Advanced Energy Technologies
Iessa Sabbe Moosa; Hussein A Kazem; Laila Masoud Rashid Al-Iessi
Abstract
Studies on renewable energy are essential topics that help find new energy sources to replace fossil sources and promote environment friendliness. Hydrogen is the most practical alternative energy carrier source that meets the mentioned purposes. The mass of hydrogen element in the Earth's water was ...
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Studies on renewable energy are essential topics that help find new energy sources to replace fossil sources and promote environment friendliness. Hydrogen is the most practical alternative energy carrier source that meets the mentioned purposes. The mass of hydrogen element in the Earth's water was calculated and found to be about 2.1×1020 kg, which is greater than the mass of the world oil reserves by about 9×105 times. In addition, essential details of water molecular arrangement were investigated in order to better understand the electrolysis of water. Also, the energy of covalent and hydrogen bonds per molecule of water was theoretically calculated and found to be about 8.17×10-19 J/molecule and 3.87×10-20 J/molecule, respectively. In the electrolysis process, two stages should be undertaken: the first stage was to break hydrogen bonds between water molecules, in which all water eclectic dipoles would align in the direction of the Applied Electric Field across the electrolysis unit. The second stage was to break water covalent bonds to generate H2 and O2 gases. Moreover, the lowest cost to generate one kg of hydrogen (0.4 $/kg) by electrolysis method using solar energy was about 0.4 $, which has already been proven, while this value was about 2.8 $/kg upon considering the average price of electricity of Oman in comparison.
Renewable Energy Resources and Technologies
Aryan Tabrizi; Mehdi Rahmani
Abstract
Reliability is an essential factor in Photovoltaic (PV) systems. Solar power has become one of the most popular renewable power resources in recent years. Solar power has drawn attention because it is free and almost available worldwide. Moreover, the price of maintenance is lower than other power resources. ...
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Reliability is an essential factor in Photovoltaic (PV) systems. Solar power has become one of the most popular renewable power resources in recent years. Solar power has drawn attention because it is free and almost available worldwide. Moreover, the price of maintenance is lower than other power resources. Since there are no moving parts in PV systems, their reliability is relatively high. It is assumed that a typical PV system can operate 20–25 years with minimum possible interruptions. However, solar power systems may fail, the same as any other systems. It is indicated by several studies that the PV inverters are responsible for major failures in PV systems, as other components are almost passive. Hence, the reliability of the inverter has maximum impact on the reliability of the whole PV system. Thus, not only assessing and calculating the reliability value of inverter is highly crucial, but also increasing its value is essential, as well. This paper calculates and evaluates the reliability of PV single-stage inverters exclusively. Furthermore, there are suggestions that improve their reliability value.
Environmental Impacts and Sustainability
Ensieh Ozgoli; Younes Noorollahi; Reza Arjmandi; Ali Mohammadi
Abstract
Climate change refers to any significant and long-term alterations in global or regional weather conditions. The impact of climate change on the industrial plans is enormous, while the water supply sector has been challenged to examine how it could continuously operate in the current situation. Optimization ...
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Climate change refers to any significant and long-term alterations in global or regional weather conditions. The impact of climate change on the industrial plans is enormous, while the water supply sector has been challenged to examine how it could continuously operate in the current situation. Optimization of energy consumption and reduction of Greenhouse Gases (GHG) emissions are some of the priorities of water companies. The objective of the study is to propose a novel evaluation approach to the feasibility of using renewable energies (solar, wind, and biomass) in the water and wastewater industry. Tehran Water and Wastewater Company consists of six regional districts and forecasting of its energy consumption, power costs, and carbon tax rates for the next ten years was done by using the regression model. The results indicated that increase in water supply and electricity consumption was evidenced by the increase in Tehran's annual population. GHG emissions were calculated in two scenarios, the first of which is based on the total supply of required electricity from conventional power plants and the second is on the generation of approximately one-third by renewable energies. In addition to the higher emissions of carbon dioxide (CO2) from diesel and oil power plants than the natural gas-fueled plants, by increasing the carbon tax to more than 30 USD per tonne of CO2, it is expected that the emissions will be reduced by 30 % in all fossil-fueled power plant types. Results showed that a small amount of tax was not effective in reducing GHG emissions.
Renewable Energy Resources and Technologies
Selfa Johnson Zwalnan; Nanchen Nimyel Caleb; Mahan Morgan Mangai; Nantim Yohana Sanda
Abstract
The effect of solar collector configurations on the thermal efficiency of an active solar water heater was investigated using TRNSYS in this study. Two versions of a solar heater were formulated on the basis of serpentine and riser-header flat plate configurations. Both models were simulated based on ...
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The effect of solar collector configurations on the thermal efficiency of an active solar water heater was investigated using TRNSYS in this study. Two versions of a solar heater were formulated on the basis of serpentine and riser-header flat plate configurations. Both models were simulated based on the same parameters and weather conditions. Besides, in accordance with clear sky and cloudy sky conditions, a parametric analysis was performed to determine the impact of varying parameters on the thermal efficiency of the two models. The results showed that the serpentine-based device model provided about 2.62 % more usable thermal energy than the riser-header configuration. In addition, both models demonstrated the same response and sensitivity to changes in the collector area and the volume of the tank. However, on a cloudy day, the efficiency of serpentine showed a significant improvement and sensitivity to flow variance with an efficiency gap of about 30 % to the riser header configuration.
Renewable Energy Resources and Technologies
Mohamed A. Barakat; Tamer Mohamed Ismail; Sayed Ibrahim Abdel-Mageed; Khaled Ramzy
Abstract
The greenhouse problem has a significant effect on our communities, health, and climate. So, the capturing techniques for CO2 remain the focus of attention these days. In this work, a Chemical Looping Combustor (CLC) was designed and fabricated with the major geometric sizes at the Faculty of Engineering, ...
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The greenhouse problem has a significant effect on our communities, health, and climate. So, the capturing techniques for CO2 remain the focus of attention these days. In this work, a Chemical Looping Combustor (CLC) was designed and fabricated with the major geometric sizes at the Faculty of Engineering, Suez Canal University. The system involves two interconnected fluidized beds. Nickel powder with 150 µm diameter as well as brown coal and liquefied petroleum gas were used as oxygen carrier, solid fuel, and gaseous fuel, respectively. The temperature distributions along the fuel reactor for LPG flow rates of 11 and 18 LPM with and without using nickel powder as well as using preheated reactor were discussed and evaluated. The effects of brown coal diameter change with and without using nickel powder were studied. The CO and CO2 concentrations at combustion gases with and without using nickel powder were conducted for LPG and brown coal fuels. A mathematical model was used to simulate the combustion in CLC using combustion and energy code. The obtained results showed that using nickel powder improved the combustion process and in case of using LPG, the flame color changed to blue which is the color of the complete combustion flame. The CO was reduced by 48.4 % and CO2 was augmented by 66.5 %. In case of using brown coal as solid fuel, CO was reduced by 53.7 % and CO2 was increased by 71.9 %. Finally, there is good agreement between the experimental and numerical results based on the determination coefficient.
Renewable Energy Resources and Technologies
Farid Jafarihaghighi; Hasanali Bahrami; Mehdi Ardjmand; Mehrdad Mirzajanzadeh
Abstract
The present study uses three generations of biodiesels and studies their effects on physical properties and exhaust gases. They are comprised of Palmaria palmate oil (third generation), Eucheuma spinosum oil (third generation), Eucheuma cottonii oil (third generation), Common wormwood oil (second generation), ...
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The present study uses three generations of biodiesels and studies their effects on physical properties and exhaust gases. They are comprised of Palmaria palmate oil (third generation), Eucheuma spinosum oil (third generation), Eucheuma cottonii oil (third generation), Common wormwood oil (second generation), Marjoram oil (second generation), Peganum harmala oil (second generation), Zingiber officinale oil (first generation), Anethum graveolens oil (first generation), and Cacao bean oil (first generation). Results show that first-generation oils gain a higher level of Calorific value around 41.16 MJ/kg than other generations. The longest carbon chain is observed by the first generation with higher unsaturated fatty acids than other generations (94.11 %). The first generation gains a higher level of density around 882 kg/m3 than other generations. Also, the first generation gains a higher level of flash point around 193 ˚C than other generations. The third generation gains a high level of cetane number at about 69, compared to other generations. The first generation gains a minimum level of cloud and pour point around -3 ˚C and -2 ˚C compared to other generations. Moreover, the third generation gains the lowest level of viscosity about 2.51 CSt compared to the first generation. The third generation gains the lowest level of NOx around 371 ppm compared to other generations. Finally, the third generation gains the lowest level of soot, CO, and HC around 0.47 Vol. %, 0.018 Vol. %, and 4.82 ppm, compared to other generations.
Renewable Energy Economics, Policies and Planning
Aychar Khajavi Pour; Mohammad Reza Shahraki; Faranak Hosseinzadeh Saljooghi
Abstract
Photovoltaic energy is a good alternative to fossil fuels due to the abundance of solar energy. In this research, the criteria for locating photovoltaic solar power plants were identified using previous studies and experts’ views and by using the Delphi method based on five socioeconomic, topographic, ...
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Photovoltaic energy is a good alternative to fossil fuels due to the abundance of solar energy. In this research, the criteria for locating photovoltaic solar power plants were identified using previous studies and experts’ views and by using the Delphi method based on five socioeconomic, topographic, power generation and distribution issues, climatological, and environmental criteria. Then, by using the GIS software, the layers of sub-criteria were classified for locating photovoltaic solar power plants. Upon identifying the proposed decision-maker units for location finding, their efficiency was calculated using the full fuzzy data envelopment analysis method in three steps. The information extracted from the layers of the sub-criteria of GIS was coded using the MATLAB software in the first step of the full fuzzy data envelopment analysis model and the decision-making units were classified into three classes of efficient, weak, and inefficient. In the second step, the values of output shortages and input surplus were determined. Finally, in the third step, efficient decision-making units were ranked using Anderson-Pearson Super Efficiency Method in full fuzzy data envelopment analysis. In order to validate the proposed method, a case study was carried out. The results of calculations showed that the north, central, and southeast areas of Sistan and Baluchestan province were among the favorable areas for photovoltaic solar power plant construction. Therefore, approximately 66 % of the province’s area has appropriate efficiency matching the sub-criteria considered to construct a photovoltaic solar power plant.
Renewable Energy Resources and Technologies
Zaiba Ishrat; Ankur Kumar Gupta; Seema Nayak
Abstract
Solar power energy continues to be a renewable and sustainable source of energy in the coming year due to its cleaner nature and abundant availability. Maximum Power Point Tracking (MPPT) is a technique used in solar power systems to extract maximum power from photovoltaic (PV) modules by tracking the ...
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Solar power energy continues to be a renewable and sustainable source of energy in the coming year due to its cleaner nature and abundant availability. Maximum Power Point Tracking (MPPT) is a technique used in solar power systems to extract maximum power from photovoltaic (PV) modules by tracking the operating point of the modules. MPPT is essential for achieving optimal power output from a solar panel, particularly in variable weather conditions. Traditional MPPT techniques are subject to limitations in handling the partial shading conditions (PSC). To ensure the tracking of maximum power point while boosting the MPPT's overall efficacy and performance, Machine Learning must be integrated into MPPT. As per the reviewer work, ML techniques have the potential to play a crucial role in the development of advanced MPPT systems for solar power systems operating under partial shading conditions and to compare the performance of existing ML-MPPT in terms of accuracy, response time, and efficacy. These review papers technically analyze the result of ML-MPPT techniques and suggest the optimum ML-MPPT tactics that are Q learning, Bayesian Regularization Neural Network (BRNN), and Multivariate Linear Regression Model (MLIR) to achieve optimum outcomes in MPPT under PSC. Further, these techniques can offer efficiency greater than 95%, tracking duration less than 1sec, and error threshold of 0.05. In the future, the reviewer may propose simulation work to compare the optimal algorithms.
Advanced Energy Technologies
Nima Amani
Abstract
Must limited energy resources and the need for energy saving make the design of buildings more efficient in terms of energy consumption. For this reason, proper orientation of buildings, use of sunlight, natural ventilation, application of consumable materials are factors that help reduce heat and cooling ...
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Must limited energy resources and the need for energy saving make the design of buildings more efficient in terms of energy consumption. For this reason, proper orientation of buildings, use of sunlight, natural ventilation, application of consumable materials are factors that help reduce heat and cooling loads. The objective of this study is to evaluate the energy efficiency of residential buildings using natural energy and optimizing the choice of materials for heat and cold saving with the Ecotect simulation software. According to analysis and simulation, it was found that the optimum materials of the main building components in a mild climate zone of Rasht city include (a) the Brick Conc block Plaster for a wall with the total radiation incident of 340 W/m2 and a radiation absorption of 240 W/m2, (b) Double Glazed-Low E for windows with the total radiation incident of 340 W/m2 and a radiation absorption of 100 W/m2, (c) Foam Core Ply Wood for door with the total radiation incident of 340 W/m2 and a radiation absorption of 200 W/m2, (d) ConcSlab- OnGround for floor with the total radiation incident of 340 W/m2 and a radiation absorption of 220 W/m2, and (e) Conc Roof Asphalt for roof with the total radiation incident of 340 W/m2 and a radiation absorption of 300 W/m2. According to an hourly temperature analysis of all stories of the building on two hot and cold days of the year and as observed by the design and material selection requirements, the building will be conditioned in an almost thermal comfort zone (below 30 degrees) in the warm season.
Renewable Energy Resources and Technologies
Sina Eterafi; Shiva Gorjian; Majid Amidpour
Abstract
In this study, the effect of covering the aperture area of a conical cavity receiver with an ultra-white glass on operational parameters of a Parabolic Dish Collector (PDC) was numerically and experimentally investigated under climate conditions of Tehran (35.44° N latitude and 51.10° longitude). ...
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In this study, the effect of covering the aperture area of a conical cavity receiver with an ultra-white glass on operational parameters of a Parabolic Dish Collector (PDC) was numerically and experimentally investigated under climate conditions of Tehran (35.44° N latitude and 51.10° longitude). The main components of the experimental setup include a dish reflector, a conical cavity receiver, Heat Transfer Fluid (HTF), hydraulic and cooling cycle, and a sun tracker. For this purpose, a conical cavity receiver with an ultra-white glass cover on its aperture was numerically modeled in Fortran software. During the evaluation, environmental parameters including ambient temperature, solar radiation, and wind speed were considered as inputs of the model. The results revealed fair agreement between the numerical and experimental data with the maximum error of approximately 4.63 % and 7.89 % for receivers with and without the glass cover on the aperture, respectively. For a steady-state analysis, the mean values of useful energy ( ) absorbed by the receiver were calculated as 1,253.25 W and 987.68 W, while thermal efficiency ( ) of the receiver was calculated as 52.61 % and 40.69 % for receivers with and without glass cover, respectively. The results revealed that both and followed a similar trend of the variations in the HTF’s temperature between the inlet and outlet of the receiver. Also, the overall heat loss coefficient ( ) and the collector heat removal factor ( ) were calculated as 420.76 W/m2°C and 0.62 for the conical cavity receiver with the glass cover.
Renewable Energy Resources and Technologies
Hossein Dastres; Ali Mohammadi; Behrooz Rezaie
Abstract
This paper deals with the problem of maximizing the extracted power from a wind turbine in the presence of model uncertainties and input saturation. An adaptive second-order integral terminal sliding mode speed control method is utilized to address this problem. The presented method benefits from the ...
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This paper deals with the problem of maximizing the extracted power from a wind turbine in the presence of model uncertainties and input saturation. An adaptive second-order integral terminal sliding mode speed control method is utilized to address this problem. The presented method benefits from the advantages of several control techniques, i.e., adaptability, robustness, finite-time convergence, and the capability of coping with the input saturation. The robust nature of the designed controller causes its high performance in facing the uncertainties in the wind turbine model. In this paper, to compensate for the effect of input saturation, an auxiliary dynamic variable is added to the tracking error and also an adaptation law is designed so that the finite-time convergence of the closed-loop system can be achieved. Moreover, to reduce the mechanical stresses which are the result of the chattering phenomenon, a second-order sliding surface is employed. The finite-time convergence of the designed controller has been proven by the Lyapunov stability theorem in which the finite-time convergence of the tracking error to zero is guaranteed. Finally, to illustrate the effectiveness and satisfactory performance of the proposed controller, two comparative simulations are carried out. The results of this comparison show that the proposed controller has less error to track the optimal speed and when the model uncertainties and input saturation occur in the wind turbine system, the proposed controller is almost 3 % more efficient than the existing controllers.
Renewable Energy Economics, Policies and Planning
Nima Amani; Abdul Amir Reza Soroush
Abstract
Traditionally, building energy model is created in isolation from the architectural building information model and energy analyses have relied on a single analysis tool. The building energy model can be generated more quickly by leveraging existing data from the BIM. The impacts of energy consumption ...
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Traditionally, building energy model is created in isolation from the architectural building information model and energy analyses have relied on a single analysis tool. The building energy model can be generated more quickly by leveraging existing data from the BIM. The impacts of energy consumption are significant in the building usage phase, which can last several decades. Due to the large share of the final energy consumption in the building sector, accurate analysis of thermal and cooling loads of a building and the efforts to reduce energy losses represent an effective way to reduce energy consumption. Therefore, it is essential to analyze the building energy performance in the design phase, which is when critical decisions are made. This study aims to investigate the impact of the building components and construction materials on building energy efficiency using Building Information Modeling (BIM) technology in a mild climate zone. After reviewing the proposed designs, the main building form was chosen for energy modeling and analysis. Then, building energy consumption analysis was performed based on the basic parameters of the building energy model. Eventually, the most optimal mode was selected by examining different energy consumption forms. This study showed that the building HVAC system always had the largest share of energy consumption. Finally, the results of parametric studies on alternative schemes of energy use intensity optimization showed that 22.59 % savings could be achieved as compared to the base building model in a 30-year time horizon
Renewable Energy Economics, Policies and Planning
Maryam Nosratinia; Ali Asghar Tofigh; Mehrdad Adl
Abstract
Given the world’s growing population and energy demand, modern methods are developed to contribute to generating alternative energies. They aim to maintain the renewability of the supplied energy and decrease environmental contaminations. Biogas is a renewable energy carrier that has recently been ...
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Given the world’s growing population and energy demand, modern methods are developed to contribute to generating alternative energies. They aim to maintain the renewability of the supplied energy and decrease environmental contaminations. Biogas is a renewable energy carrier that has recently been under consideration in Iran. One objective of such plans is to find proper locations for installing and running the existing potentials and infrastructures. In this paper, Tehran, Iran is selected as the study area which is ranked the 1st in population density and proper infrastructures available here are accessible. According to the widespread poultry and cow-breading farms in this province, bovine and aviculture excreta are considered as raw materials in producing biogas. An inference network was established in this research for evaluating the process taking into account the infrastructural parameters, geomorphological constraints, resource availability factors, and limiting parameters such as protected/prohibited areas.In this paper, the fuzzy method was used to standardize the data and the fuzzy-analytical hierarchy process method was employed to weight the locating criteria in the geographical information system. The evaluation outcomes suggested certain zones in southern parts of the province in which the industrial livestock farms become frequently widespread and the suburb areas of smaller cities on the eastern part of the province are the most proper areas for this purpose.
Renewable Energy Resources and Technologies
Toyese Oyegoke; Emo Obadiah; Francis Adah; John E. Oguche; Geoffrey T. Timothy; Ismail A. Mantu; Abubakar D. Ado
Abstract
In recent times, limitations and adverse effects of fossil fuels have significantly attracted researchers' attention to green fuels worldwide, especially in developed nations. As a way of assessing this actualization of biorefineries establishment in developing nations, this report surveys the works ...
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In recent times, limitations and adverse effects of fossil fuels have significantly attracted researchers' attention to green fuels worldwide, especially in developed nations. As a way of assessing this actualization of biorefineries establishment in developing nations, this report surveys the works done by various researches towards this great course in terms of promoting and gaining the attention of both government and private investors about the technical and economic feasibility of embracing the use of biofuels, a case of bioethanol in Nigeria. Different classes of feedstocks were reviewed for the laboratory-scale, process scale-up, pilot plant, and techno-economic studies regarding ascertaining the technical and economic feasibility of local setup of a functional biorefinery in Nigeria, which would be beneficial environmentally and economically. The literature survey unveiled that the Bioethanol yield obtained from sugarcane-juice (72.7 %), banana-stems (84.0 %), and cassava (92.0 %) were found to be of highest potential amongst other sugar-based, lignocellulosic, and starch-based feedstock, respectively. The survey further unveils that the volume of process scale-up and economic feasibility studies does not correlate well with the laboratory-scale studies. The bulk of the research works on bioethanol has given preferential attention to laboratory studies. Only a few studies have looked into the commercialization (i.e., scale-up) of the laboratory findings and the economic implications. Presently, only sugarcane and a few cassavas are reported in the literature so far. It is, therefore, necessary for further studies to give attention to the investigation of the commercializing locally developed technologies and the exploration of their economic benefits.
Renewable Energy Resources and Technologies
Reza Roohi; Masoud Akbari
Abstract
The design of novel and effective receivers is one of the most challenging aspects of solar energy harvesters, especially for Parabolic Dish Collectors (PDCs). The variation of solar flux due to the solar time and sky clearance index can affect the output thermal energy of the collector. One of the major ...
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The design of novel and effective receivers is one of the most challenging aspects of solar energy harvesters, especially for Parabolic Dish Collectors (PDCs). The variation of solar flux due to the solar time and sky clearance index can affect the output thermal energy of the collector. One of the major approaches to producing a uniform performance for the PDCs is the utilization of Phase Change Materials (PCMs). The PCMs can absorb the solar flux at its peak instances. Subsequently, due to the thermal buffering effect, excess energy is released in cases with lower solar flux. In the present study, a novel design of receiver with multiple layers of thin PCM inserted between the passages of the working fluid is numerically simulated. The simulations are designed to determine the effect of operational parameters on the performance of the examined novel receiver. According to the results, by increasing the Heat Transfer Fluid (HTF) flow rate from 60 to 90 kg/h, the system efficiency is increased from 53.8 to 66.4 %.
Advanced Energy Technologies
Tuhid Pashaee Golmarz; Sajadollah Rezazadeh; Maryam Yaldagard; Narmin Bagherzadeh
Abstract
In the present work, a Proton-Exchange Membrane Fuel Cell (PEMFC) as a three-dimensional and single phase was studied. Computational fluid dynamics and finite volume technique were employed to discretize and solve a single set of flow fields and electricity governing equations. The obtained numerical ...
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In the present work, a Proton-Exchange Membrane Fuel Cell (PEMFC) as a three-dimensional and single phase was studied. Computational fluid dynamics and finite volume technique were employed to discretize and solve a single set of flow fields and electricity governing equations. The obtained numerical results were validated with valid data in the literature and good agreement was observed between them. The main purpose of this paper is to investigate the effect of deformation of the geometric structure of a conventional cubic fuel cell into a cylindrical one. For this purpose, some important parameters indicating the operation of the fuel cell such as oxygen distribution, water, hydrogen, proton conductivity of the membrane, electric current density, and temperature distribution for two voltage differences between the anode and cathode and the proposed models were studied in detail. Numerical results showed that in the difference of voltages studied, the proposed new model had better performance than the conventional model and had a higher current density, in which at V = 0.4 [V], about a 10.35 % increase in the amount of electric current density was observed and the average increment in generated power was about 8 %, which could be a considerable value in a stack of cells. Finally, the discussion of critical parameters for both models was presented in more detail. The core idea of the results is that the Oxygen and Hydrogen utilization, water creation, and heat generation are greater in the new model.
