Estimating the potential yield of small building‐mounted wind turbines

Abstract

The wind profile in the urban boundary layer is described as following a logarithmic curve above the mean building height and an exponential curve below it. By considering the urban landscape to be an array of cubes, a method is described for calculating the surface roughness length and displacement height of this profile. Firstly, a computational fluid dynamics (CFD) model employing a k‐ϵ turbulence model is used to simulate the flow around a cube. The results of this simulation are compared with wind tunnel measurements in order to validate the code. Then, the CFD model is used to simulate the wind flow around a simple pitched‐roof building, using a semi‐logarithmic inflow profile. An array of similar pitched‐roof houses is modelled using CFD to determine the flow characteristics within an urban area. Mean wind speeds at potential turbine mounting points are studied, and optimum mounting points are identified for different prevailing wind directions. A methodology is proposed for estimating the energy yield of a building‐mounted turbine from simple information such as wind atlas wind speed and building density. The energy yield of a small turbine on a hypothetical house in west London is estimated. The energy yield is shown to be very low, particularly if the turbine is mounted below rooftop height. It should be stressed that the complexity of modelling such urban environments using such a computational model has limitations and results can only be considered approximate, but nonetheless, gives an indication of expected yields within the built environment. Copyright © 2007 John Wiley & Sons, Ltd.

Small wind turbines in turbulent (urban) environments: A consideration of normal and Weibull distributions for power prediction

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Evaluating The Impacts Of Community Renewable Energy Initiatives

“…The picture is quite different for wind (Figure 4), which shows an expected higher adoption rate in rural areas compared to higher housing density areas. Wind technology is more suited to low density settlements since wind speed and turbulence are adversely impacted by the built environment (Heath et al, 2007). Wind installations are also subject to planning regulations.…”

Evaluation of the Microlocal Wind Power Potential for the Operation of a University Wind Turbine

“…In 2007, a research was performed on the potential application of small wind turbines in urban buildings for energy generation [1]. The study consisted on modelling the wind flow through the fluid dynamics software ANSYS CFX.…”