Electricity Generation by Green Energy Sources
Reza Alayi; Salam ollah Mohammadi-Aylar
Abstract
Today, policymakers are aware of the substantial advantages of renewable energies. From the point of view of national and regional decision-makers, the first priority of preparing a com-prehensive energy plan and the second priority of determining the share of renewable energy in the total energy production ...
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Today, policymakers are aware of the substantial advantages of renewable energies. From the point of view of national and regional decision-makers, the first priority of preparing a com-prehensive energy plan and the second priority of determining the share of renewable energy in the total energy production basket of the country is an essential step in the energy policy pro-cess. In choosing from various renewable energy options, environmental dimensions are com-bined with economic, technical, and social criteria, which shows the need to combine these crite-ria, the multi-criteria of the governing decision-making space, and policy-making. Multi-criteria decision-making techniques can play an important role in choosing the best solution and option. The statistical population of this study is eight cities in the case study. The renewable energy sources studied include wind, solar, water, geothermal, and biomass. First, the potential of re-newable energy for the study areas was identified. Then the two main criteria of sustainable de-velopment: economic criteria with 5 sub-criteria and environmental criteria with 3 sub-criteria were analyzed. Finally, using the Economic Analytic Network Process (ANP) sub criterion, the environmental sub-criterion of each of the weighted renewable energies was allocated. One of the essential results of this research is the income of 72868.8 $ from solar power in Ardabil. The cost of energy is $ 2.72 kWh. The lowest cost per unit of energy produced is related to Khalkhal geothermal energy at $ 0.144.
M. Taghavi; H. Salarian; B. Ghorbani
Abstract
The present study economically evaluates a combined hydrogen liquefaction configuration using combined heat and power system, photovoltaic cells unit and liquid air energy recovery for precooling under climatic states of Yazd, Iran. The LAC recovery is used to precool hydrogen. Moreover, the cascade ...
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The present study economically evaluates a combined hydrogen liquefaction configuration using combined heat and power system, photovoltaic cells unit and liquid air energy recovery for precooling under climatic states of Yazd, Iran. The LAC recovery is used to precool hydrogen. Moreover, the cascade refrigeration systems with helium and hydrogen refrigerants are employed to supply refrigeration and liquefaction. The rest of the power required for refrigeration cycles to liquefy hydrogen is supplied by PVC unit. This integrated structure generates liquid hydrogen by receiving 5559 kW of power from PVC unit, 60.79 kg/h of natural gas, 8000 kg/h of liquid air and 1028 kg/h of gaseous hydrogen as inputs. The annualized cost of the configuration is applied to economically evaluate the hydrogen liquefaction system using renewable energies. The developed integrated structure is economically evaluated by HYSYS V10 software and m-file code in the MATLAB package. The economic research results of the hybrid cycle indicate the period of return, prime price of liquid hydrogen production and additive value are 4.249 years, 5.432 USD/kg LH2 and 1.567 USD/kg LH2, respectively. The economic sensitivity examination of the combined system reveals POR increases from 2.295 to 13.97 years and net annual profit decreases from 32.66 to 5.366 MMUSD/year by increasing the gaseous hydrogen cost from 1.4 to 3.4 USD/kg LH2. Moreover, POR increases from 2.753 to 25.07 years and levelized cost of product increases from 5.02 to 7.488 US$/kg LH2 by increasing the capital cost from 52.5 to 217.5 MMUSD.
Energy Policy
Abolfazl Dehghanmongabadi; Zahra Tahmasbnia
Abstract
In recent decades, due to the increase in the urban population and the unbridled growth of urbanization, many efforts have been made to create livable cities by emphasizing the place of renewable energy in the sustainable transportation sector. Using clean, renewable, and sustainable energy resources ...
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In recent decades, due to the increase in the urban population and the unbridled growth of urbanization, many efforts have been made to create livable cities by emphasizing the place of renewable energy in the sustainable transportation sector. Using clean, renewable, and sustainable energy resources is needed to improve social, economic, and environmental health, leading to economic development and productivity. This research tries to clarify the importance of using renewable energy in the transportation sector. In this regard, the main goal of this research is to identify effective indicators and sustainable solutions with an emphasis on the use of renewable energy in the urban transportation sector. Also, in this research, an attempt has been made to answer the questions raised by carefully examining the existing studies based on the scoping review method. The findings show that the extracted influential indicators can be categorized into environmental, economic, and social indicators, which have a significant impact on the use of renewable energy in the transportation sector. Paying attention to this index can increase the amount of use of renewable energy and the amount of desirability of the effective use of urban transportation. Finally, suggestions for strengthening sustainable development in urban transportation systems with an emphasis on the use of renewable energy have been presented.
G. Jafar Laame; W. Rahimy; S. Yerel Kandemir; E. Acikkalp
Abstract
Energy is an essential need for living, and renewable energy sources are increasingly popular sustainable energy sources. Solar energy is an inexhaustible and clean, sustainable energy source in the world. In this study, heating of a greenhouse in Herat (Afghanistan) with a heat pump using solar energy ...
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Energy is an essential need for living, and renewable energy sources are increasingly popular sustainable energy sources. Solar energy is an inexhaustible and clean, sustainable energy source in the world. In this study, heating of a greenhouse in Herat (Afghanistan) with a heat pump using solar energy was investigated. The greenhouse was kept at 20 oC, and the electricity required to operate the heat pump was taken from the grid. As a result of the analysis, the exergy/electricity input reaches 25.59 kWh, while the minimum values are equal to 0.01 kWh. It was determined that the product exergy went maximum product exergy of 6.38 kWh. Finally, it was determined that a ground source heat pump with a higher COP could be used instead of an air source heat pump.
Electricity Generation by Green Energy Sources
A.H. Bolurian; H.R. Akbari; T. Daemi; S.A.A. Mirjalily; S. Mousavi
Abstract
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 ...
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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.
Solar Thermal Engineering
Selfa Johnson Zwalnan; Nanchen Nimyel Caleb; Peter Muar Kamtu; Pahalson Cornelius Dawap
Abstract
This research proposes and evaluates an enhanced open-loop photovoltaic evacuated tube solar thermal collector hybrid energy system based on the developed multi-objective energy management strategy that manages and coordinates the hybrid system with a randomly unreliable grid power source to meet the ...
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This research proposes and evaluates an enhanced open-loop photovoltaic evacuated tube solar thermal collector hybrid energy system based on the developed multi-objective energy management strategy that manages and coordinates the hybrid system with a randomly unreliable grid power source to meet the health center's energy demand using TRNSYS software. A technical assessment of the system shows that the system is capable of meeting system load with a solar fraction of 67% even on days with an overcast sky level of radiation as low as 250 W/m2 and only 37.5% grid power availability. Overall, the system has a solar fraction of 80%. The implication of an 80% solar fraction is the large environmental benefit of reducing emissions and improved system economic viability, indicating that the formulated energy management achieves the goal of promoting renewable energy sources in the hybrid system. An economic analysis of the system revealed that it has a payback period of 6.9 years and Net Present Value of $36,985 at the end of the project's lifetime. This demonstrates that the upgrade of the traditional hybrid PVT with an evacuated tube collector operated based on the developed energy management strategy has met the goal of minimising emissions with significant environmental and economic savings.
H. Benbouhenni
Abstract
In this paper, a novel switching table (ST) of the twelve sectors direct power command (DPC) strategy of doubly-fed induction generator (DFIG) based dual rotor wind power (DRWP) is proposed using two-level hysteresis controllers for reactive and active power and feedforward neural networks (FNNs) algorithms. ...
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In this paper, a novel switching table (ST) of the twelve sectors direct power command (DPC) strategy of doubly-fed induction generator (DFIG) based dual rotor wind power (DRWP) is proposed using two-level hysteresis controllers for reactive and active power and feedforward neural networks (FNNs) algorithms. This intelligent technique was used to replace the conventional ST in order to reduce rotor flux ripple, active power ripple, total harmonic distortion (THD) of stator voltage, torque and reactive power undulations. The simulation and modeling of the proposed strategy were carried out in Matlab software. The DFIG is tested in association with a DRWP systems. The simulation results show that the DPC with FNN controller (DPC-FNN) reduced the THD value of stator voltage, rotor flux undulation, active/reactive power undulation, and electromagnetic torque ripple compared to conventional DPC strategy. It was found that the current waveform becomes purely sinusoidal with a reduction in the THD rate to 0.64%.
Tide, Wave and Hydro Power
Omid Rasooli; Masood Ebrahimi; Arash Babamiri
Abstract
In the present research, a hydrokinetic turbine is designed, and evaluated technically, economically and environmentally to produce power from low velocity currents. Firstly, the hydraulic characteristics of three existing canals is investigated and the blade profile for the turbine rotor is determined ...
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In the present research, a hydrokinetic turbine is designed, and evaluated technically, economically and environmentally to produce power from low velocity currents. Firstly, the hydraulic characteristics of three existing canals is investigated and the blade profile for the turbine rotor is determined by using the Schmitz's theory and XFOIL software. The geometrical model is then created in the SolidWorks and simulated in the ANSYS Fluent to estimate the power generation capacity. According to the results, a correlation is proposed to estimate the power generation by the turbine in different water velocities. The results are validated with the manufacturers data. The results show that the efficiency of the proposed turbine is almost 90%, the investment payback period is only 3.1 years, with a positive net present value. Environmentally, it shows that for a 1 meter in diameter turbine and water velocity of 1.5 m/s, carbon dioxide will reduce by 0.57 tons per year. The economic and environmental benefits improve greatly at higher water velocities. The results show that the proposed hydrokinetic turbine even by working in low velocity stream can supply electricity demand of rural area near the canals for the long lifespan of the turbine which is more than 25 years.
Biomass Energy Sources
G. Jebeso Morketo; M. Fekadu; T. Dajene
Abstract
The present study investigated appropriate tree species for biomass energy utilization by determining trees' dry biomass and fuel value index, taking into account that developing countries rely heavily on fuelwood for energy consumption. In Ethiopia, biomass currently meets more than 89.5% of total energy ...
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The present study investigated appropriate tree species for biomass energy utilization by determining trees' dry biomass and fuel value index, taking into account that developing countries rely heavily on fuelwood for energy consumption. In Ethiopia, biomass currently meets more than 89.5% of total energy consumption. Despite this reliance on biomass, there is a scarcity of fuelwood as well as data on dry biomass potential and fuel value indices of tree species utilized in various parts of the country. This study was done on the selection of trees for fuelwood purposes based on their dry biomass potential and fuel quality characteristics. Five highly performed Eucalyptus tree species were selected and aboveground biomass was measured using the destructive approach, whereas the fuel value index was computed using the effective method with four parameters (Calorific Value, Wood density, Ash content and Moisture content). These parameters were determined following the American Society for Testing and Materials method. Finally, aboveground biomass and carbon content varied from 13.96kg to 87.47kg and 6.03kg to 37.86 kg Tree-1, respectively. The biomass and carbon content of E. globulus and E. viminalis were both high. The maximum fuel value index was 276.34 for E. saligna. The computed fuel characteristics were statistically varied among tree species at (P ≤0.0001). Based on the tree fuel characteristics findings, E. globulus, E. viminalis, and E. saligna were identified as the best fuelwood species and were suggested for future plantations.
Ram Chhavi Sharma
Abstract
Demand of energy is increasing day by day worldwide. Also the use of non-renewable energy resources has created serious problems like global warming and air pollution. At the same time, these resources are fast depleting. So we have to look on renewable energy resources to meet the future energy needs. ...
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Demand of energy is increasing day by day worldwide. Also the use of non-renewable energy resources has created serious problems like global warming and air pollution. At the same time, these resources are fast depleting. So we have to look on renewable energy resources to meet the future energy needs. Geothermal energy resources are very versatile renewable energy resource and have wide range of potential use to fulfill the energy need of society in and around the regions of its availability. The present study critically examines the energy from geothermal resources and scope of its utilization in India. There are about 400 known thermal areas in India, each represented by hot spring. The potential geothermal resources exist all around these hot springs. The temperatures of these springs range from 34°C to 96oC. Based on cation’s and anions study, the water types are mostly NaHCO3Cl, NaCaHCO3Cl, CaMgHCO3 and NaHCO3ClSO4. The geothermal fluids from the shallow wells at Puga have been effectively applied to the refining of borax and sulphur as well as experimental space heating. India’s first power plant to produce estimated output power of 250MW will be setup at Puga. The helium content in the hot gases from Bakreswar geothermal sites varies from 1-3%. Helium exploration field stations were established in the above mentioned sites. The geothermal gradient varies from 0.7-2.5oC/m at Chhumathang geothermal field indicating the powerful geothermal region. There exists great scope to use this versatile resource for electrical as well as non-electrical applications in India.
Energy Policy
A. Aryanfar; A. Gholami; M. Pourgholi; M. Zandi Zandi; A. Khosravi
Abstract
The current work proposed a novel fuzzy-based multi-criteria decision-making method to assess the development potential of wind power plants in a country. Type-2 fuzzy logic was utilized to investigate the simultaneous effects of several technical criteria such as wind conditions, ambient temperature, ...
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The current work proposed a novel fuzzy-based multi-criteria decision-making method to assess the development potential of wind power plants in a country. Type-2 fuzzy logic was utilized to investigate the simultaneous effects of several technical criteria such as wind conditions, ambient temperature, and dust activities in a site. Iran was chosen as the case study, considering the various environmental conditions and the lack of thorough investigations in the country. The proposed method could be easily extended to apply to any region. The related technical data for all the 559 Synoptic meteorological stations in the country were collected and used as the inputs for the proposed method. Applying two-step interviews with local experts and reviewing the literature, the leading indicators and their effectiveness were defined. After developing the fuzzy rules and sets, all the sites were scored and ranked using type-2 fuzzy logic in the proposed method. Based on the final standings, priority tables were provided and the top fifty sites for implementing offshore and onshore wind power plants were introduced. Moreover, primary analysis of the collected data indicated that the provinces with high energy consumption and high PM 2.5 levels are in critical environmental conditions. Thus, these provinces need strict attention and planning for sustainable energy supply using renewable energy systems. Based on the results, several recommendations and suggestions were also mentioned to organize investment resources for a more efficient and proper power plant development as well as future studies.
Wind Energy
Cyrille Rodrigue Enone Ellah; Alban Fabrice Lionel Epée; Judith Francisca Ngbara Touafio; Cyrille Mezoue Adiang; Ruben Martin Mouangue
Abstract
This study aims to identify a favorable area for wind energy exploitation in the Littoral region of Cameroon. The study used data collected by the meteorological service at Douala International Airport. A probabilistic method based on the Weibull distribution with two parameters was used to assess the ...
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This study aims to identify a favorable area for wind energy exploitation in the Littoral region of Cameroon. The study used data collected by the meteorological service at Douala International Airport. A probabilistic method based on the Weibull distribution with two parameters was used to assess the potential of the study area. Three methods were used to determine the parameters of this distribution: the maximum likelihood method, the WAsP method, and the energy pattern factor method. Statistical tests showed that the energy pattern factor method is more efficient, but the WAsP software provided acceptable results. The WAsP software was used to generate maps of the mean wind speed and wind power density at different heights. Two specific wind turbines were considered to calculate the annual energy production. The topography of the study area, the obstructions around the logger, and the roughness of the terrain were all taken into account when generating the maps for the different characteristics. Finally, maps at heights of 50 and 100 m were created using extrapolation techniques. Two zones with the highest power density were identified. In one of these locations, the wind power density could reach 54 W/m2 at a height of 100 m and the annual electrical output from a specific wind turbine could reach 1 GWh. The corresponding location is located at latitude 4.0661° North and longitude 9.8796° East.
Geothermal Energy Systems
Hiba Mudhafar Hashim; Firas Abed
Abstract
Geothermal energy is one of the important sources of renewable energy, so researchers are greatly interested in this type of energy. One of the advantages of this type of energy is its use to heat or cool buildings because the ground temperature is fairly constant throughout the year. The research focuses ...
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Geothermal energy is one of the important sources of renewable energy, so researchers are greatly interested in this type of energy. One of the advantages of this type of energy is its use to heat or cool buildings because the ground temperature is fairly constant throughout the year. The research focuses on understanding how soil depth affects the temperature difference, the rate of heat transfer, and the overall performance of the system in Baghdad, Iraq, throughout the year by conducting a mathematical test for the ground heat exchanger and determining the number of appropriate requirements during the study to reach an equation that simulates the distribution of temperatures at depth and time. The software package (CFD ANSYS FLUENT) version 17 was used for numerical analysis. The results showed that the heat transfer rate from air to soil for cooling purposes reached its highest value of -1375 watts during July at a depth of 6 m. As for heating purposes, the maximum value during January reached 579 watts at a depth of 10 m and 499 watts at a depth of 6m. Earth air heat exchanger effectiveness was highest possible at depths of 4 and 5 m, ranging from 0.9 to 0.92 over the year. The highest value of 0.98 for the exchanger effectiveness appeared during March. The results showed good agreement between the mathematical and numerical analysis and comparison with other studies, as the percentage of deviation ranged from 1.7% to 3.6% for depths from 1 m to 10 m.
M. G. Ghebrezgabher; A. K. Weldegabir
Abstract
The request to improve electric supply in Eritrea has motivated the country to look for alternative energy resources to enhance existing power. Eritrea, being in tropics, is well situated to harvest solar energy to improve its power supply status. Although several solar energy projects have been initiated, ...
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The request to improve electric supply in Eritrea has motivated the country to look for alternative energy resources to enhance existing power. Eritrea, being in tropics, is well situated to harvest solar energy to improve its power supply status. Although several solar energy projects have been initiated, very small has been done in the country. Therefore, this research paper aims to evaluate and investigate the regional solar energy potential (SEP) in Eritrea using remote sensing data and ArcGIS applications. The digital elevation model (DEM) data was adopted to estimate the SEP and suitability of energy in the country. In addition, areal solar radiation method is applied in ArcGIS 9.3 to extract the SEP and to evaluate suitability of this energy for the development of photovoltaics (PVs) power. The results revealed that approximately 69.03%, and 30.96% of the country was excellent and highly suitable to harness SEP, respectively, and only about 0.004% was considered as unsuitable. Therefore, this research may be useful as reference for future study and to motivate the country to improve its power supply using this alternative energy.
E. Guler; S. Yerel Kandemir
Abstract
Today, the use of renewable energy sources is increasing day by day. The essential advantages of wind energy are that it is clean, low cost, and unlimited. In this paper, the wind energy potential of provinces of the Marmara region in Turkey was evaluated by multi-criteria decision-making (MCDM) methods. ...
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Today, the use of renewable energy sources is increasing day by day. The essential advantages of wind energy are that it is clean, low cost, and unlimited. In this paper, the wind energy potential of provinces of the Marmara region in Turkey was evaluated by multi-criteria decision-making (MCDM) methods. In the study, TOPSIS and PROMETHEE methods were used for analysis criteria weights were determined by two different approaches. In the first approach, the criteria weights were taken equally. In the second approach, the criteria were weighted using the AHP method. When the methods were applied by taking the criteria weights equally, Balıkesir and Çanakkale were determined as wind priority provinces in potential, while Kocaeli and Sakarya took the last rank. After the criteria weights were determined via AHP when TOPSIS and PROMETHEE methods were applied, Balıkesir ranked first, and Kocaeli ranked last. Spearman's Correlation Coefficient determined the level and direction of the relationship between the rankings obtained from TOPSIS and the PROMETHEE method. When the methods were applied, the value of “0.636” indicated that the relationship between the rankings was “positive” and “moderate”. When the criteria were weighted with AHP and the methods were applied, the correlation coefficient was obtained as “0.909”. This value indicated a “positive” and “very high” level of relationship. It was determined that the ranking results obtained when the methods were applied after the criterion weights were calculated with AHP were more supportive of each other.
TITU THOMAS
Abstract
Highly unstable absorber layers along with costly Hole Transport Materials(HTMs) have been the main problems in the perovskite-based photovoltaic industry recently. Here in this study, we intend to meet both these problems by introducing a non-toxic cesium-based absorber layer and low-cost material, ...
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Highly unstable absorber layers along with costly Hole Transport Materials(HTMs) have been the main problems in the perovskite-based photovoltaic industry recently. Here in this study, we intend to meet both these problems by introducing a non-toxic cesium-based absorber layer and low-cost material, Graphene Oxide (GO) as the Hole Transporting Layer (HTL). We use the Solar Cell Capacitance Simulator Program (SCAPS) to study the various output parameters of the device with the structure GO/Cs2TiBr6/TiO2. Physical properties like the thickness of the absorber and hole transporting layers, the role of the layer interfaces, the effect of electron affinity, optical properties like the band gap of the absorber and hole transporting layer, electrical properties like the parasitic resistance, and finally the influence of operating conditions like the temperature on the working of the device was found out. The results show that a thickness of 1 μm for absorber and 0.1 μm for HTL is suitable. Also, the optimum value for front and back interface layers were 1010 cm-3 and 1016 cm-3 respectively. Resistance values were fixed at 2 for series and 40 for shunt resistance. The electron affinity doesn’t seem to have much effect on the device performance while with the increase in temperature the performance of the device deteriorated. The highest efficiency that we obtained from the optimized device was 15.3%. In short, this unprecedented work shows that Cs2TiBr6 - GO based devices are suitable candidates to achieve highly efficient, eco-friendly, all-inorganic perovskite solar cells.
Electricity Generation by Green Energy Sources
Cedric Okinda; Dominic Samoita; Charles Nzila
Abstract
The global electricity demand is rapidly growing due to population increase and industrialization. However, the reliance on fossil fuels and other non-renewable energy resources has resulted in climate change and other unsustainability-related issues. This study aims to determine the significant penetration ...
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The global electricity demand is rapidly growing due to population increase and industrialization. However, the reliance on fossil fuels and other non-renewable energy resources has resulted in climate change and other unsustainability-related issues. This study aims to determine the significant penetration levels of Solar PV on system operations and production costs based on the current year (business as usual scenario) and the accelerated Solar PV scenario (hypothetical future) in the Kenyan electricity generation system. A one-year dynamic analysis based on an hourly time step energy demand was performed using the Energy PLAN simulation tool. The current peak demand for electricity in Kenya was established to be 2,056.67 MW with an installed capacity of 3,074.34 MW with a 2.47% contribution by Solar PV while the curtailed energy was 285.51 GWh. The simulation results showed that large-scale installations of Solar PV can decrease CO₂-equivalent emissions from 0.134 Mt to 0.021 Mt. Both scenarios are presented in terms of their ability to avoid excess electricity production regarding system operations and production costs. Increasing the share of Solar PV in electricity generation is possible by as much as 39.56% (technical) and 30.54% (market economic) simulation. Additionally, the Solar PV electricity produced increased to 19.76 TWh/year from 11.90 TWh/year. Furthermore, the Market Economic Simulation showed that the total investment annual cost for Solar PV in the hypothetical future was low at 10 mEUR/Year. Therefore, large-scale installation of Solar PV in Kenya's energy system is feasible and economically viable based on technical analysis and economic analysis.
Seyyed A. Sina
Abstract
Multi-Megawatt wind turbines have long, slender and heavy blades that can undergo extremely wind loadings. Aeroelastic stability of wind turbine blades is of great importance in both power production and load carrying capacity of structure. This paper investigates the aeroelastic stability of wind turbine ...
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Multi-Megawatt wind turbines have long, slender and heavy blades that can undergo extremely wind loadings. Aeroelastic stability of wind turbine blades is of great importance in both power production and load carrying capacity of structure. This paper investigates the aeroelastic stability of wind turbine blades modeled as thin walled composite box beam, utilizing unsteady incompressible aerodynamics. The structural model incorporates a number of non-classical effects such as transverse shear, warping inhibition, non-uniform torsional model and rotary inertia. The unsteady incompressible aerodynamics based on Wagner’s function is used to determine the aerodynamic loads. Governing differential equations of motion are obtained using Hamilton’s principle and solved using extended Galerkin’s method. The results obtained in this paper, related to clarification of the effects of angular velocity and wind speed on the aeroelastic instability boundaries of the thin-walled composite beams. The obtained results are expected to be useful toward obtaining better predictions of the aeroelastic behavior of composite rotating blades.
Odai Mowafaq Fandi; Sharul Sham Dol; Mohammed Alavi
Abstract
Renewable energy and energy sustainability are vital in meeting the exponential growth of energy demand due to increasing population and industrial needs. However, the renewable energy source unpredictability is still a concern for continuous energy supplies. United Arab Emirates (UAE) has been investing ...
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Renewable energy and energy sustainability are vital in meeting the exponential growth of energy demand due to increasing population and industrial needs. However, the renewable energy source unpredictability is still a concern for continuous energy supplies. United Arab Emirates (UAE) has been investing in renewable energy technologies over the years particularly in solar, nuclear, wind, waste to energy and hydropower. However, this seems insufficient still and the shortage of fossil fuels has triggered an alarming energy discussion. Therefore, this work aims at looking for tidal energy feasibility in the UAE apart from reviewing the shortcomings of the existing renewable energy sources in the country. Tidal energy is new but is highly predictable and if applied properly, it could add to the sustainable solutions. Based on the preliminary study, tidal lagoons with the area of 102 km2 integrated with double cycle reversible turbines can be installed at the Saqar Port in Ras Al Khaimah, UAE. The location has an average of 1.6 m head difference is sufficient to meet 1% of the total UAE’s energy demand.
J. Taghinezhad; E. Mahmoodi; M. Masdari; R. Alimardani
Abstract
The use of ducted wind turbines is developing and various scientists in their studies investigate the performance, economic analysis, and energy production by these types of turbines at a lower cost. In this paper, the ratio of wind speed increment related to free stream wind speed and turbulence rate ...
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The use of ducted wind turbines is developing and various scientists in their studies investigate the performance, economic analysis, and energy production by these types of turbines at a lower cost. In this paper, the ratio of wind speed increment related to free stream wind speed and turbulence rate in a pre-designed duct used for a horizontal three-blade wind turbine was evaluated using a hot-wire anemometer sensor and data analysis methods. The duct installed in the University of Tehran Aerospace Faculty wind tunnel and flow characterization was performed by using CTA apparatus to measure and evaluate the wind flow turbulence in the throat section of the duct, where the wind turbine was installed. Wind speed analysis was done at different speed of the wind tunnel test section and shown that in the throat section of the duct the wind speed increased with a constant slope and in more analysis, it was found the wind speed in the duct throat can be increased to 2.5 up to 3 times of free stream flow speed at a different wind speed of wind tunnel test section. From spectral analysis, it was found that only a few peaks are included in the extracted frequency that shown low turbulence inside the duct it can be concluded that the flow disturbances will not have a significant impact on the performance of the wind turbine placed inside the duct throat.
Ruben Felix; Leonidas Sayas
Abstract
Plenty of works have treated the system expansion planning problem in the presence of intermittent renewable energy resources like solar. However, most of those proposals have been approached from scenarios of plenty of data, which is not the rule in developing countries, where principal investment actors ...
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Plenty of works have treated the system expansion planning problem in the presence of intermittent renewable energy resources like solar. However, most of those proposals have been approached from scenarios of plenty of data, which is not the rule in developing countries, where principal investment actors have recently switched their focus. In contrast of operation problems where existing literature can be successfully applied since it requires short-term historical time-series gathered from the same studied plants, proposals for planning problems are almost impossible to apply because of a lack of information and measurement about renewable resources in places where no renewable plants have been previously installed. In order to fill this information gap, this paper presents a novel methodology to synthesize solar production time-series on an hourly time scale, taking as inputs aggregate data such as monthly average, maximum or minimum values of basic parameters like global horizontal insolation, air temperature, and surface albedo. The methodology comprises five steps, from data gathering to calculating electrical power produced by a solar photovoltaic system. Three application tests are performed for different places in Chile, Slovakia, and Peru to validate the proposed methodology. The results show that the methodology successfully synthesizes time-series of output power, correctly replicates typical solar resource behavior, and slightly underestimates the produced solar energy, having a discrepancy of 2.4% in the yearly total.
Biomass Energy Sources
Asefa Keneni Negassa; addisu turura
Abstract
The objective of this study was to assess and evaluate the biogas yield of food wastes generated from the main campus of Ambo University's student cafeteria in a batch anaerobic digestion. Food waste from preprocessing and leftover from the student cafeteria were collected and measured. Standard techniques ...
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The objective of this study was to assess and evaluate the biogas yield of food wastes generated from the main campus of Ambo University's student cafeteria in a batch anaerobic digestion. Food waste from preprocessing and leftover from the student cafeteria were collected and measured. Standard techniques were used to analyze the physicochemical characteristics of the various food wastes, and the barrier solution was used to assess the amount of biogas and methane produced. The daily, weekly, monthly and yearly generated food wastes were: 1,283.02; 8,883.14; 38, 489.06; 204, 448.78kg respectively and the rate of generation of food waste was 0.37kg/capita/day. The moisture content ranged from 3.4±0.78% to 93.11±0.30%; total solids from 6.9±0.30% to 96.6±0.72%, VS of TS 82.1±0.59% to 98.1±0.75%; OC from 45.6±0.33% to 54.5±0.02%, C:N from 33.8% to 20.03±0.3%. The highest average biogas and percentage of methane were measured from FLM (12500±307.16ml and (81.65±2.58%) respectively while, the lowest average total biogas and percentage of methane were from the FPK (8590.33±260.77ml and (67.15±2.47%) respectively. The findings of this study revealed that the high quantity of food waste that was readily available at the study site and that could potentially be converted into high quantity and high-quality bio-methane which could serve two purposes: producing of bio-fuels and reducing environmental degradation from the open disposal of food waste.
S. Yerel Kandemir; M. Ozgur Yayli; Emin Acikkalp
Abstract
Renewable energy is one of the sustainable energy sources, the use of which has increased considerably in recent years. Today, wind energy is an essential renewable energy source that does not have a depletion problem. In this study, electricity generation from wind energy and installed power capacity ...
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Renewable energy is one of the sustainable energy sources, the use of which has increased considerably in recent years. Today, wind energy is an essential renewable energy source that does not have a depletion problem. In this study, electricity generation from wind energy and installed power capacity in Turkey were examined. First, the data set of electrical energy production (GWh) and installed power capacity (MW) between 2010 and 2019 was used. Then, electrical energy generation and installed power capacity were evaluated with trend analysis. Three different models were used in trend analysis, and the results obtained from these models were evaluated with MAPE, MAD, and MSD. Finally, the most suitable models for electric power generation and installed power capacity were determined by evaluating the results.
Biomass Energy Sources
Tegene Tantu Geta; Mahelete Tsegaye; Gemechu Yadeta; Tewabech Alemu; Berhanu Sugebo; Dagnachew Genene
Abstract
The low bulk density of wood wastes causes handling, storage, and transportation issues, limiting its large-scale application. Pelletization can solve this inherent problem by converting biomass into dense and compact pellets with regular shape and size. To evaluate the effect of particle size and binding ...
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The low bulk density of wood wastes causes handling, storage, and transportation issues, limiting its large-scale application. Pelletization can solve this inherent problem by converting biomass into dense and compact pellets with regular shape and size. To evaluate the effect of particle size and binding agents on pellets of carbonized Pinus patula sawdust, the particle size of 0.6 mm, 1.18 mm and 2.3 mm and binding agents of cow dung, molasses and wastepaper were used. The experimental results indicated that the addition of cow dung and molasses into the carbonized sawdust resulted in increase of calorific value, decrease of ash content and increase of fixed carbon. As a result, the maximum calorific value of 28.47 MJ/kg, ash content of 2.93%, and fixed carbon of 59.32% were obtained by using molasses.The calorific value of 25.8 MJ/kg, ash content of 6.03% and fixed carbon of 52.77% were obtained by using cow dung. Whereas, addition of wastepaper into carbonized sawdust resulted in lower calorific value of 22.3 MJ/kg, highest ash value of 8.35% and low fixed carbon of 43.2%. Therefore, the use of cow dung and molasses as a binder can be considered as a sustainable approach to improve the physicochemical properties of biomass pellets.
Energy Policy
Sh. Nourifard
Abstract
In this article, three topics of wind energy science, wind energy engineering and wind energy policy of Iran have been discussed. Deciding on wind energy in the country requires comprehensive information in these three areas. Due to the increase in the capacity of renewable energy in neighboring countries ...
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In this article, three topics of wind energy science, wind energy engineering and wind energy policy of Iran have been discussed. Deciding on wind energy in the country requires comprehensive information in these three areas. Due to the increase in the capacity of renewable energy in neighboring countries and global energy transition, as well as the high potential of Iran in the field of renewable energy, especially wind energy, its culture in the country and the transfer of concepts in simple language is necessary.