This research, a part of more extensive research, presents pre-feasibility and unit sizing analysis of a hybrid system equipped with renewable energy resources in Tabriz, Iran (46°26/E, 38°06/N). This case study examines a GSM telecommunication station as a stand-alone load system. Renewable energy resources include photovoltaic (PV), a wind turbine as primary resources and fuel cell, and a battery stack as backup and energy storage systems, while an electrolyzer is used to provide the required hydrogen in the fuel cell system. Feasibility analysis and unit sizing are conducted based on climatic data such as solar irradiance and wind speed to derive an optimal model during the study. HOMER software is used to simulate the feasibility analysis, measure the size, and optimize the system. The results showed that the hybrid system performs cost-effectively. According to wind energy data and fuel-cell costs, sensitivity analysis is conducted. The load is a stand-alone GSM station that consumes 60kW per day with a maximum of 3.8kW per hour. This analysis showed that wind, PV, electrolyzer, battery, and fuel cells are not currently the best solutions. Shortly, according to improved prediction in fuel-cell technology, it is expected that this source as a backup will be the best option because it has decreased fuel-cell costs up to 65 percent. Some criteria such as size, application, and cost, have been mainly examined. These results provide excellent opportunities for this hybrid system. The result shows using fuel cells in a hybrid system is not affordable by considering current fuel cell price, and the main suggestion hybrid system configuration is PV, wind turbine, and battery, while for the nearby location of Tabriz by decreasing wind speed, using wind turbines is not feasible and more PV array should be added to the system.

Sustainable energy utilization on Mars is fundamental for the success of habitation on Mars. The two sustainable energy sources for In-Situ Resource Utilization (ISRU) with the highest potential for implementation on Mars are solar and wind. Unfortunately, the former cannot provide a reliable continuous source of energy for multiple reasons. Accordingly, wind energy is presented as a viable solution, or as a strong potential complement to solar energy. The authors investigate different sites on Mars by evaluating the available wind resources to select the most feasible location in terms of energy yield and other critical habitability criteria. This work is conducted by applying the General Circulation Model (GCM) simulation, this particular analysis of wind harvesting feasibility on Mars will be studied by employing the Mars Climate Database (MCD) model. In addition, this novel research provides a systematic approach for future energy harvesting projects on Mars. Moreover, it evaluates different potential wind turbine design concepts applicable for the Martian ISRU. The results of this research lay the foundation for future energy utilization necessary for habitation to thrive, as well as it will be a key for future exploration missions. Ultimately, this will enrich our understanding of wind turbine systems.

Electrical performance of photovoltaic (PV) cells are affected by their operating temperatures, which lead to changes in the performance of the PV panel. The performance and efficiency of a PV system is dependent upon many factors, such as its angle of incidence, accumulation of dust, speed and direction of natural winds. Particularly, angle of incidence between solar rays and PV modules is the most important. This paper will focus on developing a numerical tool for predicting the optimal tilt angle, based on wind flow over PV panel in a fixed tilt array, in order to observe the effects on performance. A 1.651 m long by 0.991 m wide solar PV panel is used in the analysis. The panel is mounted on top of a tall building and the tilt angle is fixed at one angle. This paper will observe how the PV panel is affected by wind flow and how the optimal tilt angle will change, and if it is necessary to account for convection. Increasing convective heat transfer has the potential to reduce the operating temperatures of photovoltaic solar panels thus increasing their efficiency and producing more power. This relationship was used in a numerical tool to predict the performance of the panel at different tilt angles and different wind speeds. The results show that wind speed and direction do affect power output and that designers should account for convective effects when designing positioning and orientation of solar panels.

In this study, fluid flow induced by a two stage electrohydrodynamic (EHD) gas pump in a square channel has been evaluated by experimental measurement and numerical simulations. This study is implemented for a two stage EHD gas pump with three emitting electrode configurations: 8, 24, and 56 respectively to seek the relation between the number of stages and emitting electrodes. The EHD pump is evaluated for a wide range of operating voltages starting from 20 kV up to 28 kV for further improvement in its performance over a single stage. To achieve the maximum enhancement, the emitting electrodes of the EHD gas pump are flush mounted on the channel walls so that the corona wind produced directly disturbs the boundary layer thickness and improves the heat transfer. This is leading to a higher velocity near the channel walls and resulting in an inverted parabolic velocity profile at the center of the channel, which is opposite to the fully developed velocity profile of a forced flow. Velocities are measured at three cross-sections along the tube length and then integrated to obtain the volume flow rate. The results show that EHD technique has a great potential for many engineering applications.

The current study investigates the effect of wind catcher-greenhouse integration on the micro-climatic conditions inside the green house. The potential application of wind tower in greenhouse systems for hot climatic conditions with water mist injection was carefully evaluated. The effect of various parameters such as air flow velocity, relative humidity, injector mass flow rate and injector position in the wind tower was studied. The variations in the temperature and relative humidity was observed in the greenhouse. The computational fluid dynamic analysis was carried out using Fluent and k-ε turbulence model was adopted for the analysis. A non-isothermal, multiple species, viscous and turbulent flow is pursued. It was observed that the addition of water injectors inside the wind catcher significantly reduced the temperature and enhanced the relative humidity of the air.

In this study, forced convection enhancement in a square channel by a two stage electrohydrodynamic (EHD) gas pump is numerically analyzed. This study is implemented for a two stage EHD gas pump with three emitting electrode configurations: 8, 24, and 56 respectively to seek their effectiveness in the enhancement of forced convection and pumping power requirement. The EHD gas pump is evaluated for a wide range of operating voltages starting from 20 kV up to 28 kV. The influence of electric field on the flow and temperature fields is also examined for a wide range of Reynolds numbers. The three-dimensional governing equations for the flow and temperature fields are solved using the finite volume method. The Reynolds numbers (Re) considered in this study varies in a range between 100 and 2000. At Re = 100, a maximum increase of 42% in the average Nusselt number is achieved with an applied voltage of 28 kV. The overall effectiveness of the EHD gas pump in heat transfer enhancement is evaluated by the thermal hydraulic performance parameter, (Nu/Nu 0 )/(f/f 0 ), which is always greater than unity. These results disclose that EHD technique has a great potential for many engineering applications, particularly for thermal management.

In this paper, the stochastic optimization of a horizontal-axis composite wind turbine blade is performed. Wind energy has become widely popular in recent decades as an alternative source of energy and many studies have been devoted to finding an optimal wind turbine blade using deterministic optimization. However, the actual responses of the wind turbine blade such as power generation are affected by the stochastic nature of wind, uncertainties in material properties and modeling parameters, and so on. This can have an undesirable impact on the performance and reliability of blades, which demands the consideration of uncertainties during optimization. To this end, a surrogate-based stochastic optimization of a wind turbine blade considering the influence of randomness in wind speed on power generation was studied. A slight gain in average power over the baseline blade was obtained and it demonstrated the promise of the presented framework for the design of wind turbine blades.

Three new industry standards, American National Standard/Scaffold & Access Industry Association, Inc. (ANSI/SAIA) A92.20, A92.22 and A92.24, were introduced in December 2018 to address the safe design, use and training associated with mobile elevating work platforms (MEWPs). MEWPs are defined in the new Standards as “machine/device intended for moving persons, tools and material to working positions, consisting of at least a work platform with controls, an extending structure and a chassis.” 2 This definition encompasses certain types and sizes of MEWPs such as scissor lifts, articulating boom lifts, telescopic boom lifts and straight mast boom lifts. Replacing product-specific industry standards, these three new Standards significantly change the design, testing, rental, use and training requirements associated with MEWPs. The Standards also offer greater clarity to the assigned responsibilities associated with these functions to various entities including manufacturer, dealer, owner, user, supervisors, operator, occupants, lessor, lessee and brokers. Compliance with these voluntary standards became effective June 1, 2020. 3 Recognized hazards associated with MEWPs include: tip overs associated with wind loads and contact with other obstacles, contact with power lines leading to electrocutions, caught-between the lift and other objects, falls from platform and equipment collapse. 4 This effort will analyze injury data including both fatal and nonfatal incidents associated with MEWPs to better understand the trends and quantifying many of the risks associated with the operation and maintenance of MEWPs. Injury data from the U.S. Bureau of Labor and Statistics (BLS) will be reviewed. The effort will also identify and explore how the design, use and training requirements introduced in the new industry standards address the hazards and risk associated with MEWPs.

Unmanned aerial vehicles are applicable in a lot of areas including weather condition monitoring, surveillance, and reconnaissance. They need further development in design, especially, for the turbulent atmospheric conditions. Smart materials are considered for wing manufacturing for gust alleviation whereas membranes are found suitable for such applications, and therefore, analyzing aerodynamic properties of the membrane is important. Wind gusts create an abrupt atmospheric situation for unmanned aerial vehicles during the flight. In this study, a continuous gust profile and two types of stochastic gust models, i.e., Dryden gust model and von Karman gust model are developed to study the effects of gust load on a flexible membrane wing. One of the promising ways to reduce the effects of the gust is by using an electroactive membrane wing. A fluid-structure-interaction model by coupling the finite element model of the membrane and computational fluid dynamics model of the surrounding airflow is generated. Aerodynamic coefficients are calculated from the forces found from the numerical results for different gust velocities. A wind-tunnel experimental setup is used to investigate the aerodynamic responses of the membrane wing. Dryden gust model and von Karman gust model are found comparable with a minimum variation of magnitude in the gust velocity profile. The coefficients of lift and drag fluctuate significantly with the change in velocity due to wind gust. A validation of the fluid-structure-interaction model is performed by comparing the numerical results for the lift and drag coefficients with the experimental results. The outcome of this study contributes to better understand the aerodynamics and maneuverability of unmanned aerial vehicles in the gust environment.

In this study, we develop a load estimation method and an optimization tool for community-driven planning of rural electricity systems which aims to encourage stakeholder involvement in planning processes and reinforce the sustainability of small-scale electrification projects. Electricity demand is estimated through the bottom-up construction of load profiles based on devices used in three common rural end-use sectors. A cost minimization model is then implemented to determine the least-cost capacity composition that can be installed based on the load profile and energy availability. The energy sources modeled are small-scale wind, hydro, solar (photovoltaic), diesel, and battery. In the base case, which includes the three sectors equally, most of the optimal capacity (77%) is provided by renewable energy at an average levelized cost of electricity (LCOE) of $0.05/kWh for a notional village with 500 houses. The base case results are compared to the results when each sector is respectively favored. The results show that backup dispatchable generation and batteries can both be solutions to intermittent renewables, and the choice between the two appears to depend on the load shape. We also find that the base case results are not very sensitive to the CO 2 tax, suggesting that not only are renewables cost-competitive with or without the tax, but they also benefit economically from coupling with cheap fossil fuel generators.

In comparison to fossil fuels, solar energy is a more sustainable option due to its high availability and less environmental impact. Improving the efficiency of solar farms has been a primary concern of solar energy research. Many studies focus on the control of the tilt angle of solar modules to maximize their solar radiation reception and energy generation. However, an increase in solar radiation is accompanied by an increase in module temperature, which is known to be a significant parameter that reduces the power generation efficiency. Wind is another influential factor that helps Photovoltaic systems maintain a low operating temperature by enhancing the rate of heat transfer. Therefore, solar radiation and wind behavior are both critical parameters that must be considered to optimize solar panel performance. In this paper, the effect of wind conditions on solar panel performance will be examined. The solar panel energy output model will be built by empirically considering the irradiation, ambient temperature, wind speed, and wind direction. The published weather data and energy output data for the year 2017–2018 have been collected from Antelope Valley Solar Ranch, located in Lancaster, California. Four models have been proposed and the results indicate that the model which incorporates the wind conditions has the highest accuracy in approximating the energy production of solar farms. Among the factors that affect the temperature of solar panels and further the efficiency of solar panels including solar irradiation, convection, conduction, wind plays a major role in convective heat transfer. Based on this model, the potential improvement of energy generation via introducing a horizontal installation angle and adjusting this angle monthly according to the wind conditions is further analyzed. These results will help designers improve the design of solar farms by taking into consideration the local weather conditions.

Wind farm energy production optimization has received significant attention in recent years. Much of this effort had been focused on optimizing positions of wind turbines within a wind farm domain during the design and planning stage. Optimization of wind turbine positions can reduce wake interactions of upstream turbines. In addition to optimizing turbine positions to reduce wake interactions, prior studies have shown that optimizing yaw and pitch angles can improve energy production as upstream wakes yaw away from downstream turbines. However, yaw angle optimization at the wind farm level has been difficult due to lack of low-fidelity wake model for simulating yawed wakes. Recently, an analytical wake model capable of simulating yawed turbine wakes had been developed, which enable wind farm-scale yaw optimization. In this work, a binary quadratic programming model problem formulation has been developed to optimize yaw angles of wind farms. Yaw optimization of two position-optimized layouts available in the literature were performed to study the potential of yaw optimization. In particular, we set out to understand how layout and wind farm density affect yaw optimization potential. An optimized layout of 39 turbines with 40m rotor diameter in a 2km by 2km domain was used in this study. For this wind farm, yawing optimization only improved power production by ∼1.5% under favorable wind directions. However, as wind farm power density increases by increasing rotor diameter to 60m and 80m, power production improved by ∼5% and ∼10% respectively, under favorable wind directions. Finally, another yaw optimization was performed on an optimized layout with 48 turbines of 82m rotor diameter in a 4km by 4km domain using the proposed model formulation. Under favorable wind directions, yaw angle optimization improved performance by ∼4%. The results show that yaw optimization can improve power production in the same order of magnitude as layout optimization, and that it should be considered in addition and/or in tandem to layout optimization.

Global warming and climate change have been considered as major challenges over the past few decades. Sustainable and renewable energy sources are nowadays needed to overcome the undesirable consequences of rapid development in the world. Phase change materials (PCM) are substances with high latent heat storage capacity which absorb or release the heat from or to the surrounding environment. They change from solid to liquid and vice versa. PCMs could be used as a passive cooling method which enhances energy efficiency in buildings. Integrating PCM with natural ventilation is investigated in this study by exploring the effect of phase change material on the temperature in a room fitted with a windcatcher. A chamber made of acrylic sheets fitted with a windcatcher is used to monitor the temperature variations. The dimensions of the chamber are 1250 × 1000 × 750 mm 3 . Phase change material is integrated respectively at the walls of the room, its floor and ceiling and within the windcatchers inlet channel. Temperature is measured at different locations inside the chamber. Wind is blown through the room using a fan with heating elements.

A weather data collection study is currently conducted using a renewable energy training system. The system is composed of a LabVolt trainer, two sun tracking photovoltaic solar panels and a small wind turbine. The LabVolt training system is located in one of the McCoy School of Engineering laboratories, the solar panels and the wind turbine are located in the neighborhood of the Engineering building at Midwestern State University in Wichita Falls, Texas. A set of meteorological data collecting outdoor sensors to monitor the impact of weather conditions on the power generation of the sun-tracking photovoltaic solar panels and the wind turbine have been installed on the building roof. Weather parameters such as atmospheric temperature, pressure, humidity, and rainfall are monitored using a Davis Vantage Pro 2 data collecting system. A number of LabVIEW data acquisition cards and signal processing modules are used to monitor the sun-tracking photovoltaic solar panels’ output voltage, the wind turbine output voltage, the atmospheric temperature, the solar irradiance, and the wind direction, speed, and RPM. A voltage divider has been built to step down the 90V DC voltage produced by the solar panels to 12V DC voltage required for the trainer electrical circuits. A LabVIEW data processing program is used to create instantaneous graphic displays of the collected data on a monitoring screen. The LabVolt trainer is equipped with two charge controller electronic devices, one is used for the sun tracking photovoltaic solar panels, and one is used for the wind turbine. They are used to control the flow of electrical energy through a set of electrical loading devices and a set of storages batteries. Additionally, the LabVolt trainer is equipped with two kilowatt-hour-meters counting the electrical energy consumed by the electrical loads. The trainer is also equipped with two inverters transforming the 12 V DC voltage collected from both energy producing devices to 120 V that can be used by the electrical loading devices. A brief description of all used electronic components and devices is provided in the paper, as well a detailed experiment set-up with a procedure to run them. The project has been divided into three consecutive phases. The first phase dealt with connecting the solar panels, wind turbine, and data collecting sensors to the LabVIEW data acquisition software. The second phase is currently dealing with setting up the trainer solar and wind electricity providing circuits. In the third upcoming phase, it is expected that the data collected by the sensors will be gradually archived using Excel files and analyzed for weather data correlation purposes. It is also expected that the training system will be used to teach upcoming mechanical engineering students about how to set up an independent renewable energy system and the necessary equipment required to run it.

In our daily life, we live by using many resources such as electricity and gas energy, metal products such as automobiles. When imported iron ore or coal from overseas is transported by a conveyor, it drops from the conveyor due to vibration and strong wind during transportation. At present, people are doing cleaning directly using a vacuum car in the place where the track loader cannot enter. When a person performs cleaning work using a vacuum car, accidents such as getting caught in the mouth of a hose or a conveyor might. To cope with this problem, a vacuum robot that performs cleaning work on behalf of people are developed in previous work. However, since the hose for sucking iron ore and coal is hard, these robots cannot move freely. In this research, we developed a vacuum cleaning robot that can transport a hard and heavy hose with a small and light weighted robot. The developed vacuum cleaning robot independently controls the driving part and the suction part, whereby the robot can control the position of the suction port while suppressing the repulsive force of the hose.

This work presents the design and analysis of a novel wind energy harnessing system that makes use of wind defecting structures to increase the ambient wind speed at geographic locations with relatively low wind speed. The system however reacts to highspeed wind conditions by altering the profile of the wind defecting structure in order to eliminate wind speed amplification attribute of the system, thereby protecting the wind turbine assembly at high speed wind conditions. Although increasing the wind speed is advantageous at geographic locations that the wind speed is typically low; however, from times to time, there could be sustained high-speed wind conditions at the same locations that may damage the wind turbine systems that take advantage of the wind defecting structures. The present work disclosed a wind deflecting structure formed by at least two sail-like partial cylindrical structures that are supported atop of a tower-like foundation in a symmetric arrangement, where one or more wind turbines can be installed in the space between the two partial cylinders. The two partial cylinders, each substantially in form a quarter cylinder is made of plurality of parallel ribbed-like bars, hereafter referred to as “bars” with a flexible thin material that are mechanically supported by the bars. The bars are oriented in a direction perpendicular to the ground; allowing the wing deflecting structures to accept horizonal axis or vertical axis turbines in the space between them. The function of the bars is to allow the thin material, attached to them, to assume a curved configuration substantially in the form of a quarter cylinder. The apparatus is equipped with wind speed monitoring devices, and power source and power transmission means, such as cable-pulleys, chain-sprockets, gears, or mechanical linkages that all work in concert to deploy or stow the thin material along the vertical rods depending to the magnitude of the prevailing wind speed. Preliminary computational fluid dynamics analyses have shown that the wind deflecting structure proposed here in amplifies the wind speed by a factor of 1.65.

Drying of moist porous media, such as food or pulp and paper, is an energy-intensive process. Innovative impinging jet nozzles, for instance, radial jet reattachment (RJR) and slot jet reattachment (SJR) nozzles, have been proved to be one of the efficient methods to enhance the drying rate compared to traditional in-line jet and slot jet nozzles. However, the heat and mass transfer in the region immediately underneath these nozzles are relatively inefficient. In this work, the performance of the SJR nozzle is improved by the application of electrical field, specifically, ionic wind generated in the region directly between the nozzle exit and the exposed surface of moist porous material. The numerical model is based on the coupled flow field generated by electrohydrodynamically (EHD) assisted SJR nozzle with the heat and mass transfer taking place within the moist porous media during the drying process. The simulation results show a significant secondary flow induced under the nozzle due to the ionic wind. Up to 40% drying rate enhancement has been achieved. However, the enhancement of drying rate diminishes as the air exit velocity exceeds a certain threshold. The simulation results illustrate the detailed fundamental understanding of this conjugated problem and provide a foundation for the enhancement of convective drying of moist porous materials.

Large-scale urban and forest fires, especially earthquake-induced fires may produce huge fire whirls and cause serious damage, due to the involved tornado-like strong wind, together with radiation and swirling flame. If fire whirls are generated, the danger to firefighters increases extremely. Many small-scale experiments and CFD simulations on fire whirls have already been conducted and also our previous numerical studies examined the generation of a large fire whirl in an oil tank. However, details of large-scale fire whirls have not been clarified yet. In this study, developing the previous works, additional CFD simulations are conducted to examine the generation process and particularly the stability of fire whirls. Three schemes to generate fire whirls are employed, using the 15 × 15 PMMA fuel array in windy conditions and n-heptane burning in a steel pan placed centrally on the floor in a tall channel with staggered four corner gaps, also using a channel with a single corner gap. The numerical results showed that the relationship between the fire area and the wind blowing area is important on the fire whirl generation in the PMMA scheme and n-heptane fire burning scheme in a channel. In addition to the channel gap size to produce a maximum fire whirl, the effects of channel height and horizontal channel area upon the fire whirl are examined. The wall temperatures of the channel are important to keep the swirling motion stably, particularly the wall temperature at about 300°C can stabilize the fire whirl in a channel. Also multiple small fires placed surrounding the central swirling fire can increase the stability of the fire whirl, although too strong multiple fires may destroy the stability. These phenomena may be related to the real fire whirl generation in the natural environment.

Understanding and minimizing the uncertainties in the wind energy field is of high importance to reduce the reliability risks and financial risks of wind farm projects. The present work aims to observe the levels of uncertainty in modeling the wake effect by attempting to perform statistical inference of a wake parameter, the wind speed deficit. For this purpose, an uncertainty propagation framework is presented. The framework starts by randomly sampling mean wind speed data from its probability density function (PDF), that is fed an inflow model (TurbSim), resulting in random full-flow fields that are integrated into an aeroelastic model (FAST), which results in the variability of the power and thrust coefficients of a wind turbine. Such coefficients and wind data, finally, fed the wake engineering model (FLORIS). The framework ends with the determination of the 95% coefficient intervals of the time-averaged wind speed deficit. The results obtained for the near and far wake regions introduce fundamentals in estimate the uncertainty in wind speed deficit of a single wind turbine wake and concludes that a systematic uncertainty quantification (UQ) framework for wind turbine wakes may be a useful tool to wind energy projects.

Extracting free energy has long been a goal of science but is mostly considered impossible to achieve. Natural processes having independent movement, such as rivers and wind, are often used but provide varied effectiveness. However, coordinated instability within a statically pressurized ambience can be used to extract a significant percentage of the ambient potential energy. This method creates two pathways between two adjacent points, one being a chaotic or Coriolis swirling path and the other being a direct path, thereby creating a pressure difference between the two adjacent points, which can be harvested to reduce the kinetic energy input required to perform the process. While some refer to the proposed benefits as “perpetual motion,” it is necessary to understand that 55 to 80% of the required kinetic energy would still be mechanically generated; therefore, they could be better referred to as “coordinated chaos” or a “Coriolis energy extractor” to save energy [1]. This paper studies direct returns—extracting energy directly from a static (not dynamic) ambient energy. While such returns might not be substantial in normal activities, in deepwater or underground applications (e.g., oil or gas wells), they can be significant, often equating to a 20–45% reduction in fuel use or pollutant generation. In operations that use 20,000 horsepower, this could represent a savings of 4,000 horsepower or 10,000,000 Btu/hr with no associated financial costs.