Machine 25Build a wind turbine← → step through the guidefoot and 4 anchors · 1.55 m out
Wind0 m/s
Rotor0 rpm
Furl0°
Battery25.4 V
Power0 W
What this step adds; in part B, live currentParts already in placeA 2 m rotor sweeps 3.14 m². The power in the wind is ½ × air density × area × speed³: 3,325 W at 12 m/s, of which about 15% reaches the batteries, 500 W, the rating given for a 2 m Piggott-type rotor. The model holds a tip-speed ratio of 6, so the rotor turns 688 rpm at 12 m/s (drawn at 1/6 speed so you can follow the blades), assumes charging starts at 3 m/s and that the tail starts to furl at 12 m/s, turning the rotor out of the wind so output only creeps up to about 605 W. Two 12 V batteries in series make a 24 V bank; when they are full the controller sends the power to the dump load instead. This is a guide to how the parts go together, not engineering drawings. Never climb or work under a turbine that is turning: lower it on its hinge, with the stop switch on. Raise and lower the tower only in calm weather, with nobody standing under it or in line with it, and fuse the battery leads.
