The optimum configurations of photovoltaic-micro wind hybrid power systems with battery storage are determined for 12 low windy locations in the Indian western Himalayas which will provide inputs to ...formulate a policy for the renewable energy based hybrid systems in the region. The objective is to utilize the available wind resource to supplement the solar resource for improving reliability and minimizing energy storage requirements of hybrid systems. In the analysis 7 micro turbines ranging from 1kWp to 5kWp are considered. The solar and wind resource assessment of the region shows good solar resource of 4.11–5.24kWh/m2/day but low wind resource with wind speeds ranging from 2 to 3.6m/s. However, wind speeds more than 5m/s are also available for about 1000h annually indicating potential for small wind power generation. The feasibility analysis is carried out for 12 locations using measured data for one location and NASA satellite data for other 11 locations. A 1kWp micro-wind turbine with cut in speed of 2m/s is found to generate maximum energy annually for these locations for a typical load. The methodology can be used for identifying optimum micro-wind PV hybrid systems for low wind locations worldwide.
This study presents the modelling, control and sensorless speed estimation of two micro-wind turbines deployed by the British Antarctic Survey (BAS) in Antarctica. Mathematical models for the ...generators attached to an Ampair 100 and Rutland 913 wind turbines and their experimental validation are given. A model for the wind turbines, particularly taking into account the power coefficient $C_{\rm p}$Cp versus tip speed ratio $\lambda $λ relationship, was proposed and successfully evaluated on a wind turbine emulator test rig. This study describes an analogue speed estimator board and a Kalman filter for estimating the shaft speed. These estimators use only DC-side measurements to match the characteristics of the current version of the turbine control board. The wind turbine control and speed estimators were tested on the emulator test rig using real wind data from BAS research bases in Antarctica. Using only DC-side measurements leads to low computation requirements to execute the algorithms in comparison with commonly used schemes that rely on AC measurements. The estimation algorithms are based on the model of a permanent magnet generator connected to a diode rectifier, as they can be used in a wider range of applications including DC–DC converters with maximum power point tracking algorithms.
Remote rural communities are especially vulnerable to the reliability of conventional electricity supply methods and many of these communities are post-industrial and therefore suffer from fuel ...poverty. In this study, the potential contribution to electricity supply to a remote community based on emerging technologies for embedded solar and wind renewable energy, is investigated using simulation modelling. The technologies focus on photovoltaic “slate” roof coverings and micro-vertical-axis wind-turbines. A new model for photovoltaic energy-supply is developed and combined with an existing method for modelling wind-turbine energy. These supply-side models are matched to an existing model of domestic electricity-demand for a whole village community. Results show that in excess of 40% of annual electricity-demand can be relied upon from these sources, provided that a mechanism for surplus power export is available. In the absence of surplus power management, however, only 8% of the annual electricity demand could be met by these sources.
The island of Barbados is 99% dependent on fossil fuel imports to satisfy its energy needs, which is unsustainable. This study proposes a 10
MW distributed wind energy scheme using micro wind ...turbines (WT) of horizontal (HAWT) and vertical axis (VAWT) configurations. These units are rated less than 500
W, and the scheme is hereafter referred to as mWT10. mWT10 is compared to the proposed 10
MW medium WT farm by the Barbados Light & Power Company (BL&P). The economic bottom line is the levelized cost of electricity (LCOE). The results highlight the BL&P proposal as the best economic option at BDS$0.19 per kWh, while that of both mWT10 configurations exceeds the conventional cost of BDS$0.25 by two to nine times. This is attributed to significantly higher relative installation and operational costs. However, the financial gap between mWT10 LCOE and the retail price of electricity is much smaller due to a large fuel surcharge passed on to each customer. Annual additional benefits of using wind energy include: greenhouse gas emissions savings of 6–23
kt of carbon dioxide; and anavoided fuel costs of BDS$1.5–5.3 million.
The distributed mWT10 using HAWTs competes directly with the BL&P farm, however, it provides these benefits without the visual or ecological impacts of the larger machines. Conversely, VAWTs have features that favour a visually discrete and widely repeatable scheme but suffer relatively high costs. Therefore, this study illustrates the great potential of small wind turbines to be competitive with conventional wind farms, thus challenging the small wind industry to meet its potential by producing reliable and robust machines at lower cost.
In the present work, a tool is proposed for the evaluation of micro-wind turbine performances in the Australian cities. The power curves provided by the manufacturers were combined with the ...two-parameter Weibull function representative of the local wind conditions. Calculations demonstrate that when taking into account the only wind speed magnitude, the horizontal axis micro-wind turbines have greater capacity factors than the vertical axis micro-wind turbines for similar wind conditions. Turbine capacities were then mapped over a wide range of wind conditions assuming the wind distribution characterised by Weibull parameters. By considering the market price of electricity, the income of a power source can be evaluated. The critical wind-condition boundary needed to provide a beneficial active micro-wind turbine was determined for one horizontal axis micro-wind turbine using a hypothetical income map.
Wind resource in the urban environment Derek Joseph Kearney
DOAJ (DOAJ: Directory of Open Access Journals),
01/2013, Letnik:
1, Številka:
3
Journal Article
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Renewable energy technologies, such as wind turbines, have to be considered for new building over 1000m2 under the Energy Performance of Buildings Directive (2002). Accurate assessment of the wind ...resource is a key component in the success of a wind installation. Designers, planners and architects also need wind data from urban areas to support low-energy building design, natural ventilation, air quality, pollution control, insurance and wind engineering. Over the last six years instrumentation has been installed at the Dublin Institute of Technology (DIT) in two separate locations to monitor the wind. The data has shown that the wind resource will vary quite considerably on a given site and this is due to local variations in topography, and other factors associated with wind and turbulence in the built environment. Difficulties were encountered in measuring the wind and turbulence on site. IEC 61400-12-1: 2005 states that “... analytical tools (anemometers presently available) offer little help in identifying the impact of these variables, and experimental methods encounter equally-serious difficulties.” The practical experience of measuring wind in the urban environment informed the development of a prototype anemometer that may be capable of digitally mapping accurate real-time three-dimensional data on wind speed, wind direction and, uniquely in the field of wind instrumentation, wind turbulence.
Electrification systems based on renewable energy have proven to be suitable for providing decentralized electricity to isolated communities. Electricity generated through wind power is one of the ...technical options available, although infrequently used to date. This article aims to describe the main aspects of technical design, implementation and management of the first small-scale community wind generation project for rural electrification in Peru. This project took place in the community of El Alumbre, in the region of Cajamarca, which is a mountainous area characterized by low to medium wind speeds. This project, implemented by Soluciones Prácticas - Practical Action (Peru), brought electric power to the 33 households (a total of 150 inhabitants) as well as the school and health center of the community.
Micro wind generation is becoming a favorable form of renewable energy, in and around urban centers as it is able to discretely supplement energy drawn off the national grid without requiring large ...infrastructural costs. The paper describes a method to identify regions of potential profitability based upon the assessment of its net present value (NPV). By modeling the wind conditions with the 2-parameter Weibull function the wind conditions required to ensure economic feasibility of a turbine is represented using the shape factor-scale factor (SF/SCF) mapping concept. These calculations are then superimposed to a geographical map to delimit the regional boundary of interest. When applying this method to the Australian city of Adelaide, the present concept evidences that a government fiscal policy directed at supplementing a gross energy tariff will be more effective than discounting the initial capital invested by the end user to enlarge the local region of economic feasibility.
In this study, a general overview of energy and renewable energy sources available in Australia was introduced, household's electricity situation in Australia was presented, and focus wind energy was ...conducted. A theoretical methodology for quantification and costing of selected micro wind turbines was introduced. This methodology was applied to Armidale city, New South Wales (NSW), Australia as a case study. The methodology involved utilisation of spread sheet application and HOMER software. Such methodology dealt with hourly household electric load in Armidale and hourly wind speed in Armidale as inputs and provided hourly power outputs from selected micro wind turbine as an output. As well, a sample of payback period calculations for the said selected wind turbines is calculated versus various wind speeds. This methodology can be applied to any other cities or towns. Undoubtedly, the ability of quantifying micro electricity generation resultant from micro wind turbines for a specific city or town and evaluating the share of households' electric consumption at that city or town associated with the relevant payback periods opens the gate for further studies of feasibility and visibility of micro wind turbines. PUBLICATION ABSTRACT
Machine speed is usually required for maximum power point tracking (MPPT) control of permanent-magnet synchronous generators (PMSG). In this paper, a sensorless control method is applied to the PMSG ...for micro wind turbine systems. The machine speed is estimated by using a rotor flux observer and induced EMF signal, which can solve the delay problem of the estimated speed. For vector control of PMSG for micro wind turbines, a cost-effective back-to-back PWM-type converter consisting of a two-leg three phase PWM converter and a half-bridge PWM converter is used, by which generator output power can be increased both in steady state and in transient state. The validity of the proposed control algorithm has been verified by simulation results.
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