Windmill Bearing
The windmill bearing is a block used for power generation. In order to begin generating power with one, it must have at least one sail connected (a sail frame will count as a sail). Any other block can also be attached with super glue, though it will not yield any benefit.
By default, the windmill bearing spins clockwise, though this can be changed to counter-clockwise with the wrench. For every 8 sails connected to the windmill bearing, it gains 1 RPM and 512su. (1-8 sails gives 512su, 9-16 gives 1024su, etc.)