How #WindPower Works : When you talk about modern wind #turbines, you're looking at two primary designs: horizontal-axis and vertical-axis. Vertical-axis wind turbines (VAWTs) are pretty rare. The only one currently in commercial production is the Darrieus turbine, which looks kind of like an egg beater.
savonius wind turbine - Google-haku Eräs mitoitusehdotus Savoniukselle Unfortunately, Savonius wind turbines typically only have an efficiency of around 15% - i.e. just 15% of the wind energy hitting the rotor is turned into rotational mechanical energy. (This is much less than can be achieved with a Darrieus wind turbine which uses lift rather than drag.)