How to Build a Windmill for Power Generation
- 1). Get some quality blade piping. PVC plastic sewer pipe is a great material to use to make windmill blades. It's resilient and can withstand both the weather and abuse from the wind.
One quick note here: PVC sewer piping is intended for use underground, so be sure to coat it with a heavy-duty UV resistant paint to protect it from the sun. For best results, use one with a UV inhibitor such as Titanium Dioxide. - 2). Cut your blades. Mark your pattern on the pipe with a permanent marker. The following diameters should be used, depending on the pipe's diameter: When the pipe diameter is 4 inches, the blade width at the hub should be 5 1/2 inches, and the blade width at the tip should be 3 1/2 inches. A 6-inch pipe diameter would require a 6-inch width at the hub and a 4-inch blade width at the tip. An 8-inch pipe diameter requires a 6 1/2-inch blade width at the hub and a 4 1/2-inch blade width at the tip. A 10-inch pipe diameter requires a 7-inch blade width at the hub and 5-inch blade width at the tip.
Once cut, smooth all rough edges with a sander of your choice. - 3). Make the hub. The part that connects the DC motor to the blades, the Hub's diameter must match the diameter of your motor exactly or it won't work properly. To make a hub, take a pulley that measures 6 inches in diameter and has a shaft the size of your motor diameter, then gather short pieces of 1/8 inch- to 1/4 inch-thick steel that measure about 12 inches long and 2 inches wide. You will use these to connect the blades to the hub.
Next, take a 6-inch PVC pipe measuring 48 inches in length, and quarter it around its circumference before cutting it lengthwise into four equal pieces (this will be your new wind generator blade assembly).
Be sure that your pulley fits tightly on the shaft of the DC motor and that the assembly can spin the motor. Connect the two by drilling a small hole through the pulley and shaft, and inserting a 1/8 inch bolt and nut. - 4). Measure the circumference on the pulley hub and divide this number by three (the number of blades). This will give you the distance between the blade mounting pieces of steel. The steel needs to be drilled with a 1/4-inch drill bit at the same position for each piece on the hub. Keeping the holes at least 1 inch form the outside, they should meet in the middle of the hub in order to give the generator the balance it needs to spin.
- 5). Mount your blade assembly. Attach your wind generator assembly to the top of the tower pipe so it can spin. Simply attaching a flange to the assembly body works well for this purpose, allowing the pipe to fit into it. There are several ways to attach the DC motor and hub assembly to the tower.
You can attach them to a piece of wood first and then to the flange, or you can use a piece of ABS pipe that the DC motor can fit into snugly. When doing this, be sure to cut the pipe 2 inches longer than the DC motor. Fill the blade assembly end with another piece of wood featuring a hole cut in the middle. This will allow the shaft to extend out from it so it can be connected to the entire blade assembly later. Finally, attach the flange to this piece of pipe (keeping it close to the blade assembly ), and insert the entire motor inside the protective casing. - 6). Make a tail. Using at least 1 square foot of material, the tail can be made from any type of sturdy metal. Connect it to the assembly simply by drilling a few small holes into the tail assembly pipe.
- 7). Add a pilot vane. To prevent damage during heavy winds, add a pilot vane to your windmill. The object of the vane is to turn the generator away during severe weather. Working much like a tail, the only major difference between the two is the fact that the pilot vane is mounted on the side of the body, ahead of the tail.
- 8). Install a controller. Without a controller, your batteries could become overcharged, thus destroying them. To prevent this type of damage, install a controller between your windmill and your battery bank.
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