How to Make Homemade Electric Windmills

In the environmentally-minded zeitgeist of the 21st century, many individuals seek to build their own sources of alternative energy. One such source comes in the form of wind power which an electronic windmill can produce. While not powerful enough to generate electricity for an entire modern household, homemade windmill designs do create the energy needed for one individual with light electricity needs. The following design, like many windmill plans, easily forgives modifications to any of its components including the generator, blades, rotating mount, tower, batteries, and a electronic controller.

Things You'll Need

• Generator motor
• 20-inch length of PVC pipe
• Sheet of paper
• Scissors
• Marker
• Handsaw
• Drill
• 9 bolts and washers
• 33-inch length of 2x4 wood
• Epoxy glue
• 14- by 9-inch aluminum sheet
• Twelve screws
• 2-foot by 2-foot square of plywood
• Jigsaw
• 1-inch pipe fittings (two bases with bars, two elbows, one bar)
• 1-1/4-inch Tee pipe
• Close nipple
• 1-inch reducer fitting
• 1-inch Tee pipe
• 12-inch nipple
• Four smaller stakes
• Mallet or hammer
• 10-foot long 1-1/4-inch steel conduit pipe
• Four chain link fence brackets
• Two steel hose clamps
• Four lengths of nylon rope over 10-feet long
• Four large wooden stakes
• Extension cord, over 10-feet long
• Wire cutters
• Two spade lugs
• Lead acid batteries

Instructions

1. Acquire a suitable DC generator motor, which must come with a high voltage rating, low rpm rating and high current. These specifications mean that the wind turbine will not need to turn supremely fast to generate 12 or more volts, a usable amount of energy. Old computer tape drive motors have a record as functional windmill motors but no longer exist in production and consequently cost more.

2. Build the blades of the turbine by first purchasing a 20-inch length of pipe with a 4-inch diameter. Pipe of a different diameter works as well, but the proportion of diameter to length must remain similar.

3. Wrap a sheet of paper around the pipe and cut it with scissors so that it just barely wraps around the pipe and does not overlap, cutting as straight as possible and using one edge of paper as a guide. Use the point where the ends of paper meet to draw a straight line down the length of the pipe with marker.

4. Fold the paper in half and use it to measure halfway around the pipe and draw another straight line along the paper's edge, which will mark a line exactly on the opposite side of the PVC pipe. Repeat the process and fold the paper in half again to measure quarters of the pipe's circumference and draw two more straight lines at these points.

5. Cut with your handsaw along the marked line to slice the PVC pipe in half lengthwise and then cutting each half in half for four equal sections.

6. Draw diagonal lines on each quarter of pipe by using the paper as a flexible straight edge. Place one end of the paper roughly an inch in from one corner of the pipe quarter and arrange the other end of the paper at the opposite corner of the pipe's other end. Repeat this process for three of the four blades and use the handsaw to cut these diagonal lines for those three blades. The fourth blade is just an extra part that does not go into the windmill's construction.

7. Drill the hub of the windmill to attach the blades. The hub is best built from an aluminum disk with a 5-inch diameter and 1/4-inch thickness bolted onto a toothed pulley gear on its back. Buy an aluminum disk with a hole already in the center, and drill six new holes one inch from the center, each equidistant from each other. Drill three more holes along the outer edge of the disk, approximately 1-inch from the six holes already drilled, with the three new holes placed so that they occur in a straight line from the center and through a first drilled hole. Space them so that they are equidistant and only draw a line to the center with every other first-drilled hole.

8. Drill three holes on the toothed gear that line up with the inner three holes on the disk that do not have outer edge counterparts.

9. Bolt the toothed gear flat to the back of the disk with three bolts and washers.

10. Drill two holes into the thick ends of each blade so that the two holes line up with the remaining drilled hole grouping on the front of the disk. The blades should curl up into the air, each one curling up on the same side all the way around with the drilled holes on the straight side of the blade. Bolt the blades to the aluminum disk. This completes the turbine and blade portion of the project.

11. Construct a mount and tail for the blades. Start with an approximately 33-inch long section of 2x4 wood. On one end, mix epoxy glue to glue a rectangular sheet of aluminum onto the wider top of the wood plank. The sheet should measure roughly 14-inches long and 9-inches tall and stick up out of the wood, coming all the way to the end of the plank. This forms the tail of the windmill, which will direct the blades into the wind to generate power.

12. Glue the generator motor to the opposite end of the plank so that it sticks up off of the same side as the tail. Optionally, saw a lengthwise half of another short piece of PVC pipe to cover the motor for protection.

13. Measure 7 1/2-inches from the motor end of the wood plank and screw an iron floor flange to the bottom of the plank with the center of the flange at the 7 1/2-inch mark.

14. Drill a hole through the opening of the flange through the wooden plank, which gives the wiring for the generator a place to pass through the plank and through the piping for the tower.

15. Twist a 10-inch iron pipe nipple to the floor flange.

16. Saw a circular board of plywood for the base with either the handsaw or even better, a jigsaw, so that the plywood base has a 2-foot diameter. Around the edge of the board, drill four holes for stakes later on.

17. Screw 1-inch pipe fittings onto the base to create a U-shaped structure coming up out of the base. The U-shape pipe fittings should include two circular bases screwed to the plywood, two short lengths of pipe coming up out of the bases, two 90-degree angled elbows, and a length of pipe between them. Attach a T-shaped pipe piece around the top bar of the fittings so it can swivel around, back and forth.

18. Twist a close nipple to the T-shaped pipe, then a 1-1/4-inch to 1-inch reducer fitting to the close nipple. Twist a 1-inch tee between the reducer and a 12-inch nipple. This finishes the base to the tower which holds up the mount and turbine.

19. Paint the wooden parts of the turbine mount in latex paint for weather protection.

20. Build or purchase a charge controller for the system. Purchase is highly recommended for anyone without circuitry experience, and charge controllers are easy to find through retailers of solar and wind power systems and eBay.

21. Stake the round wooden base of the windmill to the ground where the windmill will sit, driving four stakes through the holes in the base with a mallet or hammer.

22. Twist a 10-foot long length of 1-1/4-inch steel conduit pipe to the end of the base piping, which should end in the 12-inch nipple. Hold the conduit tower erect by passing four chain link fence brackets over the end of the tower and stacking them on top of each other about 8-1/2-feet up from the ground. Hold the brackets in place with two steel hose clamps on either side.

23. Tie four long stretches of nylon rope to each end of the chain link brackets and attach the rope ends to large wooden stakes set in the ground in four opposite directions. The ropes and stakes hold the tower vertical.

24. Pass the extension cord through the opening in the 2-by-4 mount down through the tower and out the 1-inch Tee fitting at the base. Cut off both ends of the extension cord with strong wire cutters and push a spade lug onto either end. Attach the end at the top to the motor generator.

25. Connect the charge controller to your battery(s) before connecting the charge controller to the spade lug at the end of the turbine connection. First, one to two lead acid batteries that can handle up to 15-volts must connect as a power receptacle, and four more should connect as storage for excess power.

References

• Mdpub: How I Home-built an Electricity Producing Wind Turbine
• Your Green Dream: Quick PVC Wind Turbine/Windmill