A twisted <a href="https://en.wikipedia.org/wiki/Savonius_wind_turbine" class="extiw" title="en:Savonius wind turbine">Savonius turbine</a> installed on a passenger boat in the United States
Dale Frost for the <a rel="nofollow" class="external text" href="https://www.flickr.com/photos/8123170@N06">Port of San Diego</a>
CC BY 2.0
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