Abstract: A vertical-axis wind turbine apparatus is disclosed. In at least one embodiment, the apparatus provides a substantially vertically-oriented main shaft. A blade assembly is coaxially aligned with and rotatably engaged about the main shaft. The blade assembly provides an at least one blade radially projecting therefrom. A housing is rotatably engaged with the main shaft and configured for selectively encompassing the blade assembly. A first screen is integral with the housing and configured for shielding a return portion of the blade assembly. A second screen is rotatably engaged with the housing and configured for selectively moving between a retracted position, wherein the second screen is positioned substantially adjacent to the first screen such that a catch portion of the blade assembly is exposed, and a deployed position, wherein the second screen is rotated away from the first screen for at least partially shielding the catch portion from the wind.

Abstract: A vertical-axis wind turbine apparatus is disclosed. In at least one embodiment, the apparatus provides a substantially vertically-oriented main shaft. A blade assembly is coaxially aligned with and rotatably engaged about the main shaft. The blade assembly provides an at least one blade radially projecting therefrom. A housing is rotatably engaged with the main shaft and configured for selectively encompassing the blade assembly. A first screen is integral with the housing and configured for shielding a return portion of the blade assembly. A second screen is rotatably engaged with the housing and configured for selectively moving between a retracted position, wherein the second screen is positioned substantially adjacent to the first screen such that a catch portion of the blade assembly is exposed, and a deployed position, wherein the second screen is rotated away from the first screen for at least partially shielding the catch portion from the wind.