The performance of a wind turbine is directly affected by the site wind condition. In urban-built locality, the wind is typified by fluctuating velocity and direction, and high turbulence intensity ...(TI). This paper investigates the impact of turbulence intensity on micro wind turbine efficiency in converting the wind energy to power. The performance of bare micro wind turbine (MWT) and diffuser-augmented micro wind turbine (DAMWT) models subject to different level of turbulence intensities is reported. Turbulence intensities ranging from ≈2% to 29% were generated by means of turbulence grids. The turbine performance is assessed in terms of the relationship between the coefficient of performance, CP and tip speed ratio, λ. Computational fluid dynamics (CFD) simulations and wind tunnel tests show that shrouding the turbine with diffuser increases the peak CP by approximately two times. Beyond a certain tip speed ratio, the performance of both MWT and DAMWT is shown to decrease with turbulence intensity, however the Cp of the DAMWT is still greater than bare MWT wind indicating the diffuser augmentation is still achievable even at high level of freestream turbulence.
•The effect of inflow turbulence intensity on bare and diffuser-augmented micro wind turbine performance is reported.•The diffuser power augmentation is still achievable at high level of inflow turbulent intensity.•Turbulence decreases the performance of both bare and diffuser-augmented micro turbine at high tip speed ratio.
•This paper studied the wind power production in an urban area.•On-site measurements were conducted to validate the simulated results.•CFD procedures were formed to determine mounting sites and power ...estimates.
There is great potential in the use of urban wind energy to form electricity generation modules over a distribution network to maximize wind power production in densely urbanized areas. The objective of this study is to therefore develop computational fluid dynamics (CFD)-based evaluation procedures to determine potential mounting sites of wind turbines and obtain estimates of wind power by taking into consideration the details of the local urban topography and boundary conditions of micro-environments. The predictions, including those of the wind velocity and direction as well as turbulence intensity, are compared with field measurements via ultrasonic anemometers and thermal flow velocity probes at 10 monitored sites over five different floors inside an objective building to validate the computational model as well as attain a better understanding of the interaction of the wind with buildings in a complex terrain. The predicted power density and turbulence intensity profiles are then used to analyze the power density, turbulence intensity and lowest mounting height for optimizing the potential mounting sites and estimates of wind power. The suggested deployment solution of using CFD for wind turbines on the studied site is clearly different from those suggested in the literature and their deficiency in providing optimum mounting sites in micro-environments. Moreover, an improved roof design with a rounded shape is proposed for the enhancement of wind power density with relatively lower turbulence intensity.
Micro wind turbine is a technology that is used to generate electricity in urban areas. The purpose of this review paper is an analysis of micro wind turbines on high-rise buildings. High-rise ...buildings are used as towers for micro wind turbines. Here is an analysis of the wind map of India for installing wind turbines. With the help of wind maps, the behavior of wind at different heights has been studied. The result of this study is to analyze how much wind power is generated in different states of India. At present nine states of India, wind energy is produced for commercial use and connected to the grid. Tamil Nadu is the largest wind power producer state. The wind flow in nine states is very good for wind power generation. Micro wind turbines have also been installed in these states and wind power generation for domestic use yields good results.
The work presents a dynamic simulation and an energy and economic analysis of two different Building Integrated Solar Technologies, namely: Building Integrated PhotoVoltaic (BIPV) collectors and ...Building Integrated hybrid PhotoVoltaic-Thermal (BIPVT) collectors. Both systems are coupled with small size Wind Turbines (WTs), to reduce the fluctuations of power production typical of solar systems. A case study is presented, referred to a hotel building, where a reversible air-to-water Heat Pump (HP) is used for space heating and cooling, driven by the electric energy provided by PV collectors and WTs. In order to optimize the HP performance in cooling mode, thermal energy is recovered from the HP desuperheater and used to produce domestic hot water (DHW). A two-stage cascade cycle HP for DHW purposes was also investigated, as a further alternative. The systems were simulated by means of a dynamic simulation model, developed in TRNSYS. The results show that the BIPV-based system is more profitable than the BIPVT one, achieving a simple payback period of about 4.5 years; for both systems, the optimum size of the WT system, for a given area of PV collectors, was also investigated.
•Building integrated photovoltaic and photovoltaic/thermal collectors are compared.•Combination of solar and wind energy to reduce fluctuations of power production.•Systems are dynamically simulated in TRNSYS environment.•Simple payback period of about 4.5 years for photovoltaic-based system.
Micro wind turbine blades for low average wind speed regions like the Arabian Peninsula, Jordan Desert and United Arab Emirates are designed and implemented. Wind profiles for two locations in UAE ...are investigated and utilized in the design and the economic analysis. Airfoils BW3, A18 and SG6043 are selected and utilized as candidates for designing micro turbine blades. Blade element momentum theory is used to design the blade 3D geometry. A methodology to optimize the blade geometry for average wind speed 5 m/s based on operational Reynolds number is developed and utilized. To account for the aerodynamic behavior over the 3D blade geometry, the power coefficient for the blades of each airfoil is obtained using the simulation software QBlade. Blades developed using airfoil BW3 showed the highest performance. A prototype is built using 3D printer and tested in open air environment (natural environment) to validate the simulation results. Comparison with existing commercial wind turbines according to cost and output power is carried out based on the concept of replacing wind turbines swept area with the equivalent array of micro wind turbines. The results show that the new design is more cost-effective and more wind energy is harnessed using equivalent swept area.
•This work provides suitable solution for low average wind speed regions such as The Arabian Peninsula.•Such design is also suitable for rural residents as well as the residential areas.•Reynolds number has considerable effect on designing low wind speed turbines.•The designed micro-wind turbine not only has better performance within the low speed range compared to the currently available commercial ones but also it is better economic choice.•Using an array of ATT turbines of similar swept area can generally produce more power than any other available commercial turbine.
Abstract
This paper analyzes the wind energy parameters for different areas with low wind energy potential using the data from the global online wind map. The performance characteristics of different ...types of wind turbines are reviewed. The generated theoretical electric energy within one year for 9 types of wind turbines is presented. Suitable wind turbines for harnessing low wind potential, that can cover the electrical needs of one household are proposed.
A plug-in hybrid electric vehicle (PHEV) uses an internal combustion engine to extend its cruising range, and to produce the electric power needed to be supplied to its electric motor when the charge ...level of the vehicle's battery becomes low and reaches a predetermined state of charge (SOC). This paper provides a better solution by replacing the internal combustion engine of a PHEV with a small-size photovoltaic (PV) module located on the roof of the PHEV, and a micro wind turbine located in front of the PHEV, behind the condenser of the air conditioning system. Thus, this study proposes a novel battery/PV/wind hybrid power source to be utilized in PHEVs. The power source equipped with vehicle-to-grid (V2G) technology is composed of a 19.2-kWh Lithium (Li)-ion battery used as the main energy storage device, and a PV module and a wind energy conversion system. A prototype of the battery/PV/wind hybrid power source has been constructed and utilized in a PHEV. Experimental verifications are presented that demonstrate utilizing the PV module and micro wind turbine adds 19.6 km to the cruising range of a PHEV with the weight of 1880 kg during two sunny days, and provides higher power efficiency (91.2%) and speed (121 km/h). Highly accurate dc-link voltage regulation and producing an appropriate three-phase stator current for the traction motor by using pulse width modulation technique are the other contributions of this paper.
Among renewable energy sources, the electrical generation at urban level from micro-wind turbines has not yet disclosed its potential. The increasing spread of micro-wind turbines may promote not ...only the decentralized generation of energy, but also helps to achieve reductions in the emission of greenhouse gases (GHGs) and to support the transition to transport system electrification. However, one of the barriers for the diffusion of micro-wind turbines in urban settlements is the difficulty to estimate its feasibility based on the local wind resource, which is highly site-specific and less predictable than other renewable sources in an urban framework (i.e. solar, biomass).
The paper deals with extensive monitoring and analysis of a micro-wind turbine performed at the outdoor development center HEnergia of HERA S.p.A. in Forlì (Italy). The micro-wind turbine was remotely monitored and data on environmental conditions and electric energy production were continuously acquired and stored by a PC. Therefore, micro-wind turbine performance was measured on-site and correlated with environment conditions. The real energy production of the micro-wind turbine was measured and a method to estimate the performances based on local wind conditions was presented. Based on the results, a simplified approach to evaluate the economic feasibility of micro-wind turbine in urban areas based on the Levelized Cost Of Energy (LCOE) concept was also presented.
•Internal combustion engine of a PHEV is replaced with PV module & micro wind turbine.•Novel battery/PV/wind hybrid power source proposed to be utilized in PHEVs.•Adding 19.6 km to the cruising range ...of a PHEV (weight: 1880 kg) during a sunny day.•Providing higher power efficiency of 91.2% and speed of 121 km/h.•Highly accurate DC-link voltage regulation.
For the first time, this study has provided a renewable energy based replacement for the internal combustion engine of a plug-in hybrid electric vehicle (PHEV). A novel battery/PV/wind hybrid power source is proposed to replace the internal combustion engine with a small-size photovoltaic (PV) module positioned on the roof of the PHEV, and a micro wind turbine located in front of the PHEV, behind the condenser of the air conditioning system. The proposed power source equipped with vehicle-to-grid (V2G) technology is composed of a 19.2 kWh Lithium (Li)-ion battery used as the main energy storage device, and a PV module and a wind energy conversion system (WECS) including the micro wind turbine used as the clean and renewable energy based auxiliary power sources. A prototype of the battery/PV/wind hybrid power source has been constructed, and experimental verifications are presented that explicitly demonstrate utilizing the PV module and micro wind turbine adds 19.6 km to the cruising range of a PHEV with the weight of 1880 kg during two sunny days, and provides a higher power efficiency and speed of, respectively, 91.2% and 121 km/h compared to the normal operation of the PHEV. Highly accurate DC-link voltage regulation and producing an appropriate three-phase stator current for the traction motor by using pulse width modulation (PWM) technique are the other contributions of this work.
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