ارزیابی پتانسیل انرژی باد شهری در یک شهر بزرگ بریتانیا با استفاده از یک مدل تحلیلی

An analytical methodology for predicting above-roof mean wind speeds in urban areas is first used to map wind speeds over four different UK cities. The methodology utilises detailed geometric data describing buildings and vegetation to calculate the aerodynamic characteristics of the urban surfaces, and accounts for the influence of building height heterogeneity and wind direction upon wind profiles. The initial objective of the work is to determine the accuracy of the methodology when using detailed geometric data describing building roof shapes in addition to their heights, to estimate surface aerodynamic parameters. By integrating detailed LiDAR (light detection and ranging) data into the methodology and comparing the predictions with measured data, predictive accuracy is found to improve significantly with respect to previous results obtained using less detailed geometric datasets which describe each building with a single height. Subsequently, a preliminary evaluation of the cumulative, city-scale potential for generating wind energy is made, using the UK City of Leeds as a case study. The results suggest that from the point of view of wind resource, 2000 to 9500 viable building-mounted wind turbine locations may exist in Leeds, highlighting the potential for this technology to be far more widely deployed than has presently been achieved. However, the calculations are shown to be highly sensitive to the viable wind speed selected, which in turn depends on financial support and technological progress. An investigation is then made into where, in general, viable roof-top turbine locations may be found. The results suggest that there are viable sites distributed throughout the city, including within the complex city centre, where at the most suitable locations above-roof wind speeds may be comparable to those observed at well exposed rural sites. However, in residential areas, consisting of groups of buildings of similar heights, it is likely that the majority of properties will be unsuitable turbine locations. The wind maps and methodology described in this paper may be utilised by turbine suppliers and customers for assessing the viability of potential sites, as well as being instructive for policymakers developing subsidies for small-scale renewable energy projects.