The novel cross-axis-wind-turbine (CAWT) is a new type of wind turbine that has the capability to extract energy from multi-directional wind that is commonly found in urban areas due to the interaction of airflows between high-rise buildings.
Its ability to operate in areas with complex wind pattern and low wind speed overcomes the weaknesses of the vertical and horizontal axis wind turbines (VAWT and HAWT). The novel wind turbine consists of vertical and horizontal blades arranged in a cross axis orientation, therefore enabling it to function with airflows coming from horizontal and vertical directions.
The horizontal blades serve as the radial arms that link and support the vertical blades and the hubs through specially designed connectors to form the CAWT. Any airflow streams channeled to the bottom of the turbine interact with the lower and upper radial supporting-arms, therefore maximising the wind energy potential that can be extracted.
Viewed from the top, the upper and lower radial arms can be considered as a double-layered HAWT that extracts energy from the vertical wind. Moreover, the lift created by the interaction between the vertical airflow and the horizontal blades creates aero-levitation forces which reduce bearing friction in the generator, hence extending the lifespan of the wind turbine.
Initial studies have shown that the CAWT can overcome the problem of self-starting ability of a conventional VAWT, and produce better performance output by up to 2.5 times. In conclusion, the CAWT presents an innovative outlook on the future of wind turbines, creating significant opportunities for the use of wind energy devices and therefore alleviating dependencies on fossil fuel power plants.