| Due to the increasing environmental and economic cost of fossil fuels, alternative sources of energy are needed. One such source is energy wind energy. Much of the current wind turbine research focuses on large-scale wind turbines. An alternative approach is small-scale wind turbines designed specifically to produce power at low wind speeds. This thesis investigates the design and testing of these turbines. Concerns specific to small-scale design, such as low Reynolds number flow, separation, and low wind speed power generation are addressed. A test apparatus was developed to validate the design procedure, and specific methods to increase power generation under these conditions, such as spanwise and axial roughness, two, three, and four-bladed systems and tip-speed ratios of 1, 3, and 7, were investigated. While many of these methods increased system efficiency, roughness was found to dramatically improve performance, reaching up to 126% increase in power output at a wind speed of 10 mph. |
