Journal of Renewable Energy and Environment
Volume:9 Issue: 4, Autumn 2022

Rural tourism is an important factor in achieving economic, social, and cultural development. Given that villages in Iran do not have access to permanent electricity or are associated with high power outages, the provision of sustainable electricity through renewable energy can cause more tourists to choose these villages as their ultimate goal. Therefore, in this paper, for the first time, a hybrid system has been evaluated based on solar energy in 10 tourism target villages in Iran using HOMER software. This study investigated the design of the system with real and up-to-date data on equipment and fossil fuel prices taking into account transportation costs as well as a comprehensive study of energy-economic-environmental with electricity generation approach to the development of rural tourism. The results demonstrated that for the studied stations, the LCOE parameter was in the range of $ 0.615-0.722, the percentage of power supply by solar cells was in the range of 90-99 %, and the prevention of pollutants was 33.9-277 kg/year. According to the results, Meymand village is the most suitable and Mazichal village is the unsuitable station in the field of energy supply required by solar cells. The production pollution in the studied stations is mainly CO2 and results from the operational phase of the project and its amount is 979.5 kg/year. Given that the rural tourism has grown and become a solution for development, the authors hope that the present work results can be used as a perspective to help energy and rural tourism decision-makers. 

A solar energy operated two-row weeder was developed for weeding in wetland paddy crop. Its major components are power source, power transmission system, weeding wheels, and a float. The power source comprised a DC motor, solar panel, and power storage unit with maximum power point tracker and motor controller. Solar panel/power storage unit through a motor controller supplied power to the DC motor and it was transmitted to the shaft of the weeding wheel through a dog clutch. A pair of wheels attached with jaw tooth and plane blades at wheel circumference was used for carrying out weeding and movement of the weeder in the field. A float was used to prevent sinkage of the weeder in soft soil which, in turn, ensured stability during operation. The developed weeder could do weeding at a rate of 0.06 ha per hour with field efficiency, weeding efficiency, and plant damage of 83.3 %, 83 % and 2-3 %, respectively. As compared to cono-weeder, the cost of weeding was 41.2 % lower due to higher field capacity and fewer labor requirements. Annual use less than 4.13 ha for the developed weeder was found uneconomical for carrying out weeding. The developed powering system comprising solar photovoltaic panels could supply power to do weeding continuously for 2 hours with a maximum discharge of 20 % from the battery.

Light is a critical parameter for plant growth such that providing enough light for the plant can ensure better quality and higher yield in greenhouses. In many areas, in the cold seasons of the year, not enough natural light reaches the plant. Thus, to compensate for the natural light deficit, artificial light is used. Since the use of artificial light leads to energy consumption, effective parameters in the energy consumption of the lighting system such as available natural light, greenhouse shape, and the on-off plan of the lighting system should be considered. In this paper, available natural light is estimated based on greenhouse structure in five cities of Iran. Then, the natural light deficit was investigated. Finally, to achieve clean cultivation, the utilization of photovoltaic panels is investigated to compensate for the electrical energy needed for supplementary lighting. The results show that although Iran is recognized as a region with high solar energy potential, natural light is not enough for optimum tomato lighting demand. Using supplementary lighting in greenhouses could compensate for the lack of natural light in proportion to the capacity of the lighting system. In 73.22 % to 91.32 % of days in the period of September to April, the natural light is not sufficient for optimum lighting. Therefore, 98 to 377 electricity is needed to supply power for supplementary lighting system. Accordingly, the photovoltaic area and its associated with costs to compensate electrical energy consumption for the supplementary lighting is estimated to be 0.47 to 2.58 per m2 of greenhouse area, which is equal to $ 171.08 to $ 939.12 per m2 of greenhouse area, respectively.

The ability of power systems against severe events shows their increased resilience, which in turn reduces the operation costs and recovery time of the system. This study presents a new resilient stochastic unit commitment model using the frequency change rate as a new index of system resilience. Furthermore, uncertainties of wind and solar power plants and demanded load are considered simultaneously. In the proposed method that considers the occurrence of a destructive incident in important production units in the worst-case scenarios and by using the generation capacity, adaptive frequency load shedding, and interrupting contracts, an effective strategy was provided to solve the unit commitment problem of thermal units to prevent instability in system frequency and to minimize unwanted load shedding. The proposed model was tested and evaluated on the IEEE 39-bus system with a wind power plant and a solar power plant. Moreover, the results obtained from simulation were reported. The effectiveness of this innovative approach in increasing the resilience of the power system against different degrees of uncertainty was confirmed based on the results.

The issue of power supply in hospitals is of special importance because of its direct effect on people's health conditions and vital treatment and care measures. Hospitals are among buildings with high energy consumption. The possibility of using renewable sources in their energy supply is one of the issues and challenges that specialists encounter. This paper discusses the possibility of installing a small solar power generation unit on a hospital rooftop to improve the quality of power supply systems. The case study is a hospital located in Tehran, Iran. For this purpose, the hospital energy system was modeled with the Design-Builder software. The obtained results were validated based on the actual consumption of the model specified in the hospital energy bills. According to the modeling step results, the annual consumption of the current energy system was 3.08 GWh of electricity and 4.23 GWh of gas. In the second step, a renewable power generation unit consisting of photovoltaic panels and battery was designed for the hospital's roof using PVsyst software. The designed power generation unit could produce 132 MWh of solar energy per year, of which 85 MWh may be sold to the main grid. The techno-economic and environmental feasibility study for the proposed system was performed using HOMER Pro software. The evaluation results revealed that considering the 20-year lifetime of the project, the proposed system achieved a lower energy cost and lower net present cost than the current system. Environmental assessment of the model by considering emission penalty indicated that the proposed system emitted fewer pollutant gases into the environment than the current system. Sensitivity analysis was also applied to investigate the effect of discounting and diesel fuel price variation on the system’s energy cost. According to the results, a 4 % increase in the discount rate leads to a 14 % growth in the cost of energy for the project. Also, there was a direct relation between enhancement of the expected inflation rate and raising the net present cost of the project.

Significant growth of the wind power market has led to a dramatic increase in the scale and capacity of wind turbines over the past decades. As these extreme-scale structures are expected to pose a wide range of challenges, an innovative concept which both lightens blade's mass and improves their aerodynamic performance, is vital for the future of rotor's design. In the present study, modeling and evaluating of an innovative pre-aligned rotor design based on SANDIA SNL100-00 wind turbine blade were accomplished. To evaluate the aerodynamic performance of the proposed rotor, CFD simulation was used as a well-developed technique in fluid mechanic. In the new rotor design, the swept area was increased using an equal blade length and the blade sections were more appropriately aligned with the wind flow compared to the reference model. This enhancement attained due to transferring the bending position from the root to a certain point alongside the length of blade. According to simulation assessments, this modification led to the overall improvement of main performance parameters in terms of the mean power and the applied torque on the blades. The simulation revealed that the novel concept is capable of increasing the mean power coefficient by 13.21 % compared to the conventional rotor designs. Analysis of the axial induction in front of the rotor plane displayed a greater drop in the flow velocity streaming up to the rotor, which could lead to have a more efficient configuration for harnessing the upcoming wind's power.

This study used ternary substrates consisting of honne, neem, and yellow oleander (HONOYO) oil blend to produce methyl-esters for sustainability of raw materials for biodiesel synthesis. A biomass-based catalyst from calcined mixed agro-wastes consisting of kolanut pod, cocoa pod, and plantain peel ash was employed to transesterify the blend. A two-step method was adopted to convert HONOYO into methyl-esters. Taguchi L9 experimental design tool was used to ascertain the interactive effects of microwave irradiation power (W), Methanol/oil ratio (MeOH), time (min), and agro-wastes synthesized catalyst ASC (wt %) on the yield of methyl-esters from HONOYO. Results demonstrated that at 3:1 MeOH, microwave power of 150 W, ASC of 1.5 wt %, and reaction time of 1 minute, a yield of 80.96 % was achieved. HONOYOB satisfied ASTM D6751 and EN 14214 standards. Performance evaluation of the process input variables suggests weight of ASC as the most significant process parameters for HONOYOB yield. This work authenticates that biomass catalyst from agricultural wastes can adequately be applied to synthesis biodiesel effectively from blends of non-edible oils to supplement fossil diesel.

The solar photovoltaic system is modeled in Simulink using Matlab. Boost converter, FOTIDC controller, and Reduced Switch Multilevel Inverter are all included in this PV system (RSMLI). With regard to solar photovoltaic systems, the focus of this study is on the Fractional Order Tilt Integral Derivative Controller (FOTIDC). In the suggested control technique, Hybrid Genetic Particle Swarm Jaya Optimization is used to optimize the control parameters (HGPSJO). Jaya Optimization (JO) is a hybrid of the Particle Swarm Optimization (PSO), Genetic Algorithm (GA), and GA/PSO algorithm optimization techniques, combining the best of each for improved control executions. Control performance is enhanced using a fractional calculus-based technique to redesign the Tilt Integral Derivative Controller (TIDC) in order to reduce noise and harmonic distortions. Harmonic distortion and voltage magnitude are reduced by applying the proposed control method to the PV system. Simulated Matlab environments are used to test the stability, robustness, and stability of the proposed system as well as its capacity to reduce harmonic distortions. It is also compared to other well-known control techniques in order to ensure that the real-time implementation is properly validated.

The presence of increasing concerns and enforcement of growing regulations over environmental pollution are nowadays at play. The pollution arising from mineral oils is among the major concerns. With the gradual reducation of the world oil reserves, an increasing pressure comes into play for finding sustainable alternatives. Being appealing alternatives, vegetable oils consist of different fatty acids; however, they cannot be applied directly to internal combustion engines owing to their poor oxidation stability and high pour point value. Biolubricants are considered to be a new generation of lubricants, which are renewable and biodegradable and are produced from the chemical modification of vegetable oils. There are few studies investigating the feasibility of using the mixture of fatty acids as biolubricant feedstock. In this study, epoxidation, oxirane ring opening with palmitic acid and p-Toluenesulfonic acid, esterification reaction with octanol, and reaction of the remaining hydroxyl group with stearic acid were applied to modify the mixture of oleic and linoleic fatty acids and produce biolubricant. For this purpose, the IR spectrums of each epoxide, monoester, diester, and triester products were obtained and analyzed. At the end of the experiments, monoester, diester, and triester were obtained with 94 % yield, with 96 % yield, and with 98 % yield, respectively. Eventually, the final product was found with physicochemical properties comparable with the physicochemical properties of the lubricant standard ISO VG10.

Nowadays, the Permanent Magnet (PM) generator has become an instrumental tool for wind power generation due to its high performance. In this study, an optimal design is established to provide a cost-effective multiphase outer-rotor PM wind generator (OR-PMWG). The cost of the generation system (generator and power converter) as well as the annual energy output must be optimized to ensure cost-effective PM wind generation. In fact, the main novelty of this paper lies in the presentation of an accurate model of OR-PMWG and the investigation of the design variables affecting annual energy output and the generation system cost (GSC). In this respect, a multi-objective framework is presented to make satisfactory agreement among all objectives. At first, the main optimal design objectives namely generation system cost and annual energy output are optimized separately and then, a multi-objective optimization is established, in which all the objectives are considered simultaneously. In order to tackle these optimization problems, Genetic Algorithm (GA) is adopted herein to determine the design variables. It is also shown that simultaneous optimization with 71.39 (MWh) AEO and 2651.51 (US$) GSC leads to a more optimal design for a PM wind generation system. In addition, the effectiveness of the presented optimal design is demonstrated by making a comparison between a prototype outer-rotor PM wind generator and the theoretical counterpart. Finally, a finite element analysis (FEA) is carried out for the validation of the outcomes obtained from the proposed optimal design.