Amin Baghani
Abstract
In recent years, the growing demand for energy and environmental requirements has focused much attention on solar energy as a renewable source. The building rooftops are the most suitable places for installing photovoltaic panels in urban and rural areas. In large districts, accurate estimation of radiation ...
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In recent years, the growing demand for energy and environmental requirements has focused much attention on solar energy as a renewable source. The building rooftops are the most suitable places for installing photovoltaic panels in urban and rural areas. In large districts, accurate estimation of radiation received by the rooftops requires the existence of detailed 3D information about them. This research aims to provide an efficient method to estimate solar energy production potential from the rooftops using the UAV photogrammetry method and GIS. The proposed method considers both the factors of the geometric features of the rooftops (slope and azimuth) and the shadow of the adjacent features. A threshold for minimum separated suitable rooftops for installing photovoltaic panels received radiation and rooftop area. Converting received radiation into electrical energy was made based on the average level of current world technology for solar panels. Providing a comparison between the amount of electricity produced during the four seasons and throughout the year as an effective parameter related to the consumption pattern is another achievement of this research. The findings of this research can be used in various fields, such as electricity and the construction industry, as well as macro planning, to benefit from clean energy. The results of implementing the proposed method for a rural area showed that out of a total of 543 existing roofs, 422 roofs are suitable for installing solar panels. Also, for these rooftops, the potential to produce 5741 MWh of electricity will be available in one year.
Transformation of Generated Electricity by Renewable Energies to Grid
A. Ghaedi; M. Mahmoudian; R. Sedaghati
Abstract
The widespread growing of electric vehicles (EVs) in distribution networks could be a variety of challenges and opportunities for the electricity network. This issue is important because the owners of electric vehicles are trying to maximize their profits, which in turn can cause many problems such as ...
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The widespread growing of electric vehicles (EVs) in distribution networks could be a variety of challenges and opportunities for the electricity network. This issue is important because the owners of electric vehicles are trying to maximize their profits, which in turn can cause many problems such as increased losses, congestion, increase network costs, etc. in distribution networks. Therefore, it is required to study different aspects of this new technology such as reliability and failure rate. For this purpose, the presented paper introduces a reliability model based on the Markov theory for different types of electric vehicles, and the main novelty is to determine the impact of the failure rate of the composed components of the each electric vehicle on the overall failure of the vehicle. In the proposed reliability models for these electric vehicles, the failure of the main composed components is considered. To compare different types of electric vehicles from reliability point of view, numerical results associated with the reliability evaluation of these vehicles are given. It is deduced from the numerical results associated to the reliability evaluation of different types of electric vehicles that the reliability of the compound plug-in hybrid electric vehicle is more than the other technologies.
S.E. Kashfi; A. Ebrahimi; S. Kazemi
Abstract
Compliant offshore tension leg platforms (TLP) are adaptive platforms with a vertical mooring system. These types of platforms are usually used in deep water. Adding sufficient initial tension to the mooring, the vertical movements of the structure will be reduced. Tendons, body, and deck are different ...
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Compliant offshore tension leg platforms (TLP) are adaptive platforms with a vertical mooring system. These types of platforms are usually used in deep water. Adding sufficient initial tension to the mooring, the vertical movements of the structure will be reduced. Tendons, body, and deck are different components of this platform, with the body being the most important in terms of hydrodynamic forces, weight, and cost. In this study, an investigation is done on a TLP with a wind turbine by numerical analysis. The boundary element and the finite volume method were carried out in this work in the Caspian Sea. Then the platform was analyzed at a depth of 150 meters, under the influence of wind, current, and irregular waves with one and 100-year return period, and at a zero-degree wave angle. The results of the two numerical approaches are very close and almost identical. The tension leg platform was stable in the different irregular waves. Also, the response amplitude operator calculated using two numerical methods has a good agreement.
Desalinations Systems with Renewable Energies
Neda Mehtari; Mostafa Kahani; Mohammad Zamen
Abstract
The current research focuses on the utilization of three waste water streams from a power plant located in southwestern Iran for desalination purposes and to prevent the waste of heat from the boiler blowdown stream while reducing carbon dioxide emissions by preheating the cooling water. Three different ...
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The current research focuses on the utilization of three waste water streams from a power plant located in southwestern Iran for desalination purposes and to prevent the waste of heat from the boiler blowdown stream while reducing carbon dioxide emissions by preheating the cooling water. Three different scenarios are simulated using the Thermoflow-GT master 23 software, considering the conditions of power plant. The optimal values for the top brine temperature (TBT) of cooling water and the mass flow rate of the hot steam are selected by sensitivity analysis. The premier scenario consists of eight stages, with five stages dedicated to heat recovery (HGS) and three stages for heat rejection section (HRS). The optimal value for the TBT of cooling water is determined to be 90℃, the produced freshwater capacity in the desalination unit is found to be 1.69 kg/s, and the gain output ratio (GOR) of the system is about 3.60. The proposed unit requires 0.47 and 10.15 kg/s of hot steam and cooling water, respectively and the overall heat transfer coefficient is 2069.2 W/m2 ℃. In addition, the feasibility of utilizing a solar farm to generate the necessary thermal energy for the system is being evaluated.
Energy Policy
M. Shiri Dezaki; Z. Zandian Sefiddashti; M. Jahangiri; A. Haghani; A. Tahmasebi
Abstract
The outbreak of Coronavirus disease (COVID-19) in late 2019 and its eventual transformation into a global pandemic caused a shock wave across countries. The renewable energy (RE) sector, which has always been one of the leading areas for promoting environmental sustainability, has not been spared from ...
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The outbreak of Coronavirus disease (COVID-19) in late 2019 and its eventual transformation into a global pandemic caused a shock wave across countries. The renewable energy (RE) sector, which has always been one of the leading areas for promoting environmental sustainability, has not been spared from the epidemic. The integration of the effects of the epidemic on the global economy and the fluctuation of oil prices due to global quarantines around the world increased the impact of this disease on the RE industry. Although the COVID-19 crisis has had a negative effect on efforts to develop RE, analysts believe that in the future, more of the world's energy needs will come from RE sources. The International Energy Agency (IEA) has claimed that RE consumption is likely to increase because people tend to have clean and sustainable energy sources such as wind, water, and solar energy more than before. In the present work, the effects of the COVID-19 outbreak on environmental changes, energy consumption, the need to use RE, investments made in the field of RE, and the well-being of the people of the world are examined and details and results will be discussed. The main aim of the present work is to review the studies of researchers on the impact of COVID-19 disease on the environment and RE.
A. Zare; M. Simab; M. Nafar
Abstract
Due to the growing demand in the electricity sector and the shift to the operation of renewable sources, the use of solar arrays has been at the forefront of consumers' interests. In the meantime, since the production capacity of each solar cell is limited, in order to increase the production capacity ...
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Due to the growing demand in the electricity sector and the shift to the operation of renewable sources, the use of solar arrays has been at the forefront of consumers' interests. In the meantime, since the production capacity of each solar cell is limited, in order to increase the production capacity of photovoltaic (PV) arrays, several cells are arranged in parallel or in series to form a panel in order to obtain the expected power. Short circuit (SC) and open circuit (OC) faults in the solar PV systems are the main factors that reduce the amount of solar power generation, which has different types. Partial shadow, cable rot, un-achieved maximum power point tracking (MPPT) and ground faults are some of these malfunctions that should be detected and located as soon as possible. Therefore, effective fault detection strategy is very essential to maintain the proper performance of PV systems to minimize network interruptions. The detection method must also be able to detect, locate and differentiate between SC and OC modules in irradiated PV arrays and non-uniform temperature distributions. In this paper, based on artificial intelligence (AI) and neural networks (NN), neutrons can be utilized, as they have been trained in machine learning process, to detect various types of faults in PV networks. The proposed technique is faster than other artificial neural networks (ANN) methods, since it uses an additional hidden layer that can also increase processing accuracy. The output results prove the superiority of this claim.
Biomass Energy Sources
Mohammad Khoobbakht; Mohsen Soleymani; Kamran Kheiralipour; Mahmoud Karimi
Abstract
The effect of biodiesel percentage in biodiesel-diesel blends on the engine under different engine operation conditions must be predicted to achieve high performance. The goal of the present paper was to model brake power, brake torque, thermal efficiency, and specific fuel consumption of a diesel engine ...
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The effect of biodiesel percentage in biodiesel-diesel blends on the engine under different engine operation conditions must be predicted to achieve high performance. The goal of the present paper was to model brake power, brake torque, thermal efficiency, and specific fuel consumption of a diesel engine fueled by algal biodiesel-diesel blends. The response surface methodology was successfully applied to model the performance indicators of biodiesel-diesel fueled OM 314 diesel engine at various engine loads and rotational speeds. Brake power, torque, and thermal efficiency increased by increasing engine load. Increasing engine rotational speed caused increase in brake power whereas highest brake torque and thermal efficiency was obtained in medium engine rotational speed. Increase of biodiesel percentage caused decrease in. Biodiesel had negative effects, but it had lower effects than engine load and rotational speed on the change of the engine performance indicators. Brake specific fuel consumption decreased by increasing load but it was lowest in medium rotational speeds. A quadratic model was suitably fitted to predict the effects of input-output variables with statistical significance of 1% probability level. The coefficient of determinations for prediction of the engine brake power, brake torque, thermal efficiency, and brake specific fuel consumption were 97.63, 99.74, 97.41, and 95.72%, respectively. The result of the present work is useful to find optimum biodiesel percentage and engine load and rotational speed to achieve high performance fuel blends.
Solar Thermal Engineering
Mahdi Rezaei Rad; Rouzbeh Shafaghat; Amirhossein Aghajani afghan; Behrad Alizadeh Kharkeshi
Abstract
This experimental study introduces a solar humidifier-dehumidifier desalination model as a type of open-air-open water (OAOW) system; also, a new condenser with thermoelectric modules is applied in the dehumidifier unit. The experimental tests were done by considering climate conditions in the north ...
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This experimental study introduces a solar humidifier-dehumidifier desalination model as a type of open-air-open water (OAOW) system; also, a new condenser with thermoelectric modules is applied in the dehumidifier unit. The experimental tests were done by considering climate conditions in the north of Iran (Mazandaran province, Babol), and the effect of the inlet air's temperature and flow rate on the system's functional characteristics and condenser was investigated to improve the performance. Sensors measured the data related to the fluid temperature and humidity of the cycle at different points; other data was also gathered by psychrometric chart and EES software. The results section investigates water generation rate, GOR, coefficient of performance (COP), and condenser efficiency. The results showed that the highest water production is 420 g/hr, and the highest GOR is 0.19. Also, the water production rate and COP increase as the inlet air temperature rises. At temperatures lower than 75o Celsius, due to the air saturation, the maximum point of the water production and COP occurs at a flow rate of 0.022 kg/s. at high temperatures, increasing the flow rate raises water production, and on the other hand, the COP in the condenser is 0.8 at the highest point. According to the economic analysis done for the proposed model, the freshwater cost is 0.098-0.049 $/year for one liter.
Mojtaba Ghiyasi
Abstract
Data envelopment analysis (DEA) is a mathematical programming approach for the performance basement of the production units from a production economic view. In this paper, we analyze the performance of Iranian wind power plants (IWPP) using DEA. In the second phase of the study, we utilize the inverse ...
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Data envelopment analysis (DEA) is a mathematical programming approach for the performance basement of the production units from a production economic view. In this paper, we analyze the performance of Iranian wind power plants (IWPP) using DEA. In the second phase of the study, we utilize the inverse DEA approach as a valuable method for the future planning of the IWPPs. In this step, we considered five different scenarios from a short-run up to a long-run planning for electricity production by renewable energy. In the short-run we just need more capacity factor rather than capital. Although in the mid-run we did not presume capital extension, the result suggested this. In the end, in the long-run planning extension in not only capacity factor but also more investment in the higher technologies is a requirement for reaching the desired electricity production.
Tide, Wave and Hydro Power
Hosein Jokar; Abuzar Abazari; Reza Dorostkar
Abstract
One of the main needs for dhow vessels is fuel for diesel generators that generate electricity, which in turn is used in refrigerators and electronic devices. Concerning the development of new devices for electricity generation such as point absorber wave energy converters, in the present research for ...
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One of the main needs for dhow vessels is fuel for diesel generators that generate electricity, which in turn is used in refrigerators and electronic devices. Concerning the development of new devices for electricity generation such as point absorber wave energy converters, in the present research for the first time, the feasibility of installing such converters on the hull of the dhow vessel and their performance is being examined. These WECs expanded on the sea-free surface level during anchoring time. Depending on the relative angular displacement between the WEC and the dhow hull the electricity is produced. In the present study, the simulations are done based on the diffraction theory in Ansys AQWA. The results showed that for considering four installed WECs, the maximum output power of 400 kilowatts is produced, which is an acceptable amount of energy for supplying the common electronic devices on the dhow vessel. In addition to this, it has been shown that the hybrid system of the dhow and WECs in the anchoring mode has fewer dynamic responses compared to a single dhow without WECs. Such conditions can be utilized for the comfort of the passengers or special operations during the anchoring time. It was also observed that the buoy size does not have a considerable effect on the production power and dynamic response of the platform, while the length of 2 m for the lever and angle of 90 degrees of the incident wave is optimum from the production power point of view.
Solar Thermal Engineering
Fatemeh - Ahani; Elham - Sarkardehi; Maryam - Ansarimanesh; Hamed - Moslehi
Abstract
Approximately 40% of fossil energy consumption in Iran is attributed to office and residential buildings. Therefore, optimizing energy consumption and managing energy demand in these buildings is essential. A key aspect of this optimization is the building's outer shell, which plays a vital role ...
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Approximately 40% of fossil energy consumption in Iran is attributed to office and residential buildings. Therefore, optimizing energy consumption and managing energy demand in these buildings is essential. A key aspect of this optimization is the building's outer shell, which plays a vital role in heat control. One effective method for reducing energy consumption in buildings is the implementation of double-skin facades (DSFs), which have demonstrated superior performance compared to single-skin facades. Considering the high energy consumption of office buildings in Iran, this research aimed to minimize energy use in the computer center building at Shahrood University of Technology. The research methodology consisted of a literature review, field measurements, and simulation. The validity of the research data was evaluated against field measurements, and its accuracy was confirmed. Using Design Builder version 7 simulation software, twelve models of double-skin facades were analyzed and categorized into box window facades and shaft boxes, both located on the southern elevation of the computer center building. The results indicate that the double-skin facade featuring a box window reduces the building's energy consumption by 6.4% to 9.7% compared to the single-skin facade. Additionally, the double-skin facade of the shaft box also decreases energy consumption, ranging from 5.5% to 9.3% compared to the single-skin facade.
Energy Policy
Hossein Heirani; Seyed Mohammad Shobeiry
Abstract
This paper analyzes the life cycle of Iran's wind energy innovation system through a co-evolutionary framework that examines the interplay between the system and its contextual environment. Our analysis reveals that the system is transitioning from formation to growth, but remains vulnerable due ...
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This paper analyzes the life cycle of Iran's wind energy innovation system through a co-evolutionary framework that examines the interplay between the system and its contextual environment. Our analysis reveals that the system is transitioning from formation to growth, but remains vulnerable due to its high dependence on contextual factors. By examining three historical phases, we demonstrate how political, geographical, and sectoral contexts have critically influenced the system's development trajectory. The research identifies key systemic problems across functional, structural, and contextual dimensions, showing how their dynamics have either facilitated or hindered growth. Based on these findings, we propose policy recommendations focused on infrastructure stabilization, institutional support, and contextual management to overcome barriers and enhance the system's resilience and performance. This co-evolutionary perspective offers policymakers a novel framework for understanding and addressing the complex challenges facing renewable energy innovation systems.
Electricity Generation by Green Energy Sources
Kaveh Soleimani; Ataollah Gharechae; Mohammad Javad Ketabdari
Abstract
This research evaluates the feasibility of utilizing wave energy at Chabahar Port as an alternative power source. The first part of the study analyzed seasonal and annual wind and wave characteristics, as well as the directional distributions of winds and waves, utilizing long-term buoy measurements. ...
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This research evaluates the feasibility of utilizing wave energy at Chabahar Port as an alternative power source. The first part of the study analyzed seasonal and annual wind and wave characteristics, as well as the directional distributions of winds and waves, utilizing long-term buoy measurements. The extractable power output was determined based on the wave scatter diagram for Chabahar Port and the power matrix of various existing wave power devices. The average annual wave power at this location is 4.1 kW/m. However, wave power exhibited significant variation across the autumn, winter, spring, and summer seasons, averaging 1.46, 1.48, 4.4, and 6.94 kW/m, respectively. Among the thirteen wave power concepts evaluated, the Wave Dragon and the 1500 kW Pelamis demonstrated the best performance. The Wave Dragon is identified as the preferred wave power device for Chabahar Port, considering its power production capability, seabed compatibility, and adaptability to diverse meteorological conditions. Additionally, RETScreen Expert software was employed to conduct a cost and emissions analysis, indicating that the Wave Dragon and Pelamis can reduce greenhouse gas emissions by 719.7 and 351.6 tons of carbon dioxide, respectively. Consequently, the Wave Dragon offers the most economical power solution for Chabahar Port, with a greater reduction in greenhouse gas emissions.
Energy Policy
Seyed Zaman Hosseini; Farhad Hossinzadeh Lotfi; Mahnaz Ahadzadeh Namin
Abstract
Assessment of progress and regression of organizations is necessary to determine their performance and determination of the efficacy of managerial decisions, supply usage, and weak and strong points for the senior managers and decision-makers. They can improve the efficiency of the units based on this ...
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Assessment of progress and regression of organizations is necessary to determine their performance and determination of the efficacy of managerial decisions, supply usage, and weak and strong points for the senior managers and decision-makers. They can improve the efficiency of the units based on this assessment. In this paper, using data envelopment analysis, the performance of regional electric companies of Iran in 2015 and 2016 is assessed. Because of semi-positive and negative indexes, the Slack-Based Measure (SBM) model of efficiency is developed for the 16 regional electric companies of Iran. To determine progress and regression in 2016 compared with 2015, models are proposed to compute the indexes of productivity. Finally, solving the proposed models, the Malmquist productivity index is computed for regional electric companies of Iran with 18 input, intermediate and output indexes and considering the amount of production of renewable energies as one of the important output indexes because of the irrefutable necessity of this kind of energies in the world. Their progress and regression are obtained using the Gams software showing progress in two companies, and regression in 13 companies while one company had neither progress nor regression. Studies performed show that agility of the organizational structure, financial and human resource limitations, sanctions and imbalance between the actual price of production of one kilowatt-hour of electricity and its sale price are most effective factors on the progress and regression of the companies.