Sharif Digital Repository

The capacity factor is an important wind turbine parameter which is ratio of average output electrical power to rated electrical power of the wind turbine. Another main factor, the AEP, the annual energy production, can be determined using wind characteristics and wind turbine performance. Lower rated power may lead to higher capacity factor but will reduce the AEP. Therefore, it is important to consider simultaneously both the capacity factor and the AEP in design or selecting a wind turbine. In this work, a new semi-empirical secondary capacity factor is introduced for determining a rated wind speed at which yearly energy and hydrogen production obtain a maximum value. This capacity factor... 

The emerging environmental consequences of overdependence on fossil fuels have pushed many countries to invest in clean and renewable sources of power. Countries like Iran where these sources can be found in abundance can take advantage of this potential to reduce their dependence on fossil fuels. This study investigated the feasibility of the standalone use of a hybrid renewable energy system (HRES) to power buildings in the Bostegan village in the Hormozgan province of Iran. Technical, economic, and environmental assessments were performed with the help of the Hybrid Optimization of Multiple Energy Resources (HOMER) software, and the optimal configuration for the system components was... 

The emerging environmental consequences of overdependence on fossil fuels have pushed many countries to invest in clean and renewable sources of power. Countries like Iran where these sources can be found in abundance can take advantage of this potential to reduce their dependence on fossil fuels. This study investigated the feasibility of the standalone use of a hybrid renewable energy system (HRES) to power buildings in the Bostegan village in the Hormozgan province of Iran. Technical, economic, and environmental assessments were performed with the help of the Hybrid Optimization of Multiple Energy Resources (HOMER) software, and the optimal configuration for the system components was... 

In this study, the performance of a system consisting of an organic Rankine cycle (ORC) for generating power and an electrolyzer for producing hydrogen with a zeotropic mixture as working fluid to recover waste heat in a geothermal flash-binary cycle is investigated from energy and exergy point of view. The study also investigates the effect of using zeotropic mixtures with different compositions as the ORC's working fluid rather than pure fluids. Using the particle swarm optimization (PSO) algorithm, the optimization is performed to maximize the power production of the entire system. The results show that using the combination of pentane with other pure fluids as working fluid led to... 

While Afghanistan's power sector is almost completely dependent on fossil fuels, it still cannot meet the rising power demand of this country. Deploying a combination of renewable energy systems with hydrogen production as the excess energy storage mechanism could be a sustainable long-term approach for addressing some of the energy problems of Afghanistan. Since Badakhshan is known to have a higher average wind speed than any other Afghan province, in this study, a technical, economic, and carbon footprint assessment was performed to investigate the potential for wind power and hydrogen production in this province. Wind data of four stations in Badakhshan were used for technical assessment... 

Increasing energy demand has led to a substantial growth in the use of wind energy across the world, which can be attributed to the low initial and running costs and rapid and easy deployment of this technology. The development of hydrogen from wind energy is an excellent way to store the excess wind power produced, as the produced hydrogen can be used not only as clean fuel but also as input for various industries. Considering the good wind potentials of Yazd province, the variety of industries that are active in this area, and the central location of this province in Iran, which gives it ample access to major transport routes and other industrial hubs, hydrogen production from wind power... 

Due to population growth and industrial development, Iran is facing the challenge of energy supply in various industrial, power plant, agricultural, and residential sectors. While most of Iran's energy supply comes from fossil fuels, these fuels have devastating environmental impacts. Therefore, Iran has to invest more in its renewable energy sources. Given that many locations of Iran have significant wind, solar, and geothermal potential, this study used a combination of SWOT, multicriteria decision-making approaches, and game theory to identify the best renewable energy development plans for the country. The Stepwise Weight Assessment Ratio Analysis (SWARA) technique was applied to weight... 

Hydrogen as an energy carrier can play a significant role in reducing environmental emissions if it is produced from renewable energy resources. This research aims to assess hydrogen production from wind energy considering environmental, economic, and technical aspect for the East Azerbaijan province of Iran. The economic assessment is performed by calculation of payback period, levelized cost of hydrogen, and levelized cost of electricity. Since uncertainty in the power output of wind turbines may affect the payback period, all calculations are performed for four different turbine degradation rates. While it is common in the literature to choose the wind turbine based on a single criterion,... 

Due to population growth and industrial development, Iran is facing the challenge of energy supply in various industrial, power plant, agricultural, and residential sectors. While most of Iran's energy supply comes from fossil fuels, these fuels have devastating environmental impacts. Therefore, Iran has to invest more in its renewable energy sources. Given that many locations of Iran have significant wind, solar, and geothermal potential, this study used a combination of SWOT, multicriteria decision-making approaches, and game theory to identify the best renewable energy development plans for the country. The Stepwise Weight Assessment Ratio Analysis (SWARA) technique was applied to weight... 

Power consumption of wellbore drilling in oil and gas exploitations count for 40% of total costs, hence power saving of WBM (water-based mud) by adding different concentrations of Al2O3, TiO2 and SiO2 nanoparticles is investigated here. A high-speed Taylor–Couette system (TCS) was devised to operate at speeds 0–1600 RPM to simulate power consumption of wellbore drilling using nanofluids in laminar to turbulent flow conditions. The TCS control unit uses several sensors to record current, voltage and rotational speed and Arduino microprocessors to process outputs including rheological properties and power consumption. Total power consumption of the TCS was correlated with a second-order... 

An API standard drilling fluid was investigated from laminar to turbulent flow conditions using an in-house-built viscometer at speeds from 200 to 1600 RPM. A power-based method was applied to obtain the apparent viscosity and the shear stress of the water-based drilling mud (WBM) in the annulus of the viscometer. Then, a MATLAB optimization program was developed to obtain model parameters for five rheology models integrated in a generalized Herschel-Bulkley-Extended (HBE) model and two widely used 4-parameter models in drilling industry. It is found that the Bingham, Cross, and HBE rheology models have precisely matched the WBM measurements in the viscometer. A generalized Reynolds number... 

Observing the growing energy demand of modern societies, many countries have rec-ognized energy security as a looming problem and renewable energies as a solution to this issue. Renewable hydrogen production is an excellent method for the storage and transfer of energy generated by intermittent renewable sources such as wind and solar so that they can be used at a place and time of our choosing. In this study, the suitability of 15 cities in Fars province, Iran, for renewable hydrogen production was investigated and compared by the use of multiple multi-criteria decision-making methods including ARAS, SAW, CODAS, and TOPSIS. The obtained rankings were aggregated by rank averaging, Borda... 

Renewable hydrogen production plays a key role in transitioning to a hydrogen economy. For this, developing countries are encouraged to keep up with industrialized nations. As such, this study seeks to evaluate the potential of all capital cities of Iran in terms of solar-based hydrogen production and prioritize the nominated alternatives. This step is highly valued because finding the most suitable place for this purpose can lead to substantial outcomes and consequently avoid failure. Therefore, here a 20-kW solar power plant is simulated by PVsyst 6.7 software and meteorological data of 31 capital cities is extracted using Meteonorm 7.1 software. Considering all losses associated with... 

Drying is a common practice for delaying deterioration, preserving quality, and easier prolonged storage of agricultural products. According to the climatic and geographical conditions of Arsanjan County, Fars, Iran. So far, many studies have been conducted on the design and use of various barriers on absorber plates with the aim of increasing heat exchange and subsequently increasing the efficiency of air heaters and solar dryers. However, the effect of using the metal of the sewing machine bobbin on the performance of these dryers has not been studied yet. Therefore, in this study, for the first time, this metal and also pipes containing PCM (phase change material) were used as a barrier... 

With the advent of new technologies and globalization of business, supply chains have turned into indispensable tools for gaining competitive advantage. The application of new technologies like blockchain can benefit sustainable energy supply chains by improving chain and logistics operations in the areas of trust, transparency and accountability, cooperation, information sharing, financial exchanges, and supply chain integration. However, the efforts to adopt such technologies in supply chains tend to face many challenges and challenges, which can seriously threaten their success. Therefore, it is crucial to carefully examine the challenges to blockchain technology application. This... 

A technical-economic assessment was carried out in this study to determine the possibilities for wind and solar power generation in Afghanistan’s Helmand province. The results showed that most of the province has a solar irradiance of over 400 W/m2, and also showed that wind and solar power generated in the province can be up to twice as cheap as the official price of renewable power in Afghanistan. The most suitable site for solar and hydrogen production was found to be Laškar Gāh, where solar and hydrogen can be produced at a cost of 0.066 $/kWh and 2.1496 $/kg-H2, respectively. In terms of wind power production and hydrogen production from wind, the most suitable site was Sangīn, where...