Development of wind turbine system for building envelope and evaluation of its energy potential

Abstract

Building integrated wind turbine (BIWT) installations have gradually increased with an interest at surrounding renewable energy sources in urban area. The typical application method for conventional BIWT systems is to install many small-size wind turbines on the rooftop or edges of the building, so it has its limitation on installable area. This research proposes a new type of BIWT system by directly utilizing the building skin, which is an unused and unavailable area in all conventional BIWT systems. The proposed system exploits the static pressure on the building envelope introducing a guide vane, that is able to effectively collect the incoming wind and increase its speed for a rotor. To this end, theoretical backgrounds and several important design issues for the guide vane as well as the rotor were thoroughly investigated and accordingly addressed. A series of computational fluid dynamics (CFD) analyses was performed to determine the optimal configuration of the proposed system for specific conditions. The performance evaluation tests were conducted in the wind tunnel with the prototype with the specially designed guide vane and rotor. The wind tunnel tests demonstrated that the proposed BIWT system accelerates the wind speed to a sufficient level and consequently increases the power coefficient significantly. Finally, this research assessed an energy potential of the proposed BIWT system in global urban area. The amounts of energy generation and consumption of an office building integrated with the proposed system was estimated through the CFD analysis and the building performance simulation, respectively, and the system’s performance was evaluated by the ratio of the power production to the energy consumption. The results provide wind energy potential of the proposed system following its orientation in six different cities. As a result, the proposed system is positively evaluated as a promising wind power conversion system for several global urban areas.