It’s like a manual window roller in a Tesla

 

 

An ingenious cleaning robot being used to clean off the dust from solar panel farms in the desert.

Credits: iwasdoingfinelurking and imgur via Panah Rad, Rad GIFs & Videos and Google+, Stanislav Sinyagin

The old Dutch windmill

 

There isn’t a single windmill owner in Holland who doesn’t have a second job, for when there is no wind. Johnny Ball
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