TOWERS for Windynation systems

Discussion in 'Frame Construction' started by Minnesota, Nov 6, 2010.

  1. Minnesota

    Minnesota WindyNation Engineer

    I'm beginning to compile information on towers, mainly aimed at supporting the Windtura 500 frame. I'd rather buy a proven tower kit, such as a guyed tower using a shedule 40 water pipe, but get the pipe locally. The ones I have discovered thus far like this are the 24-foot and 30-foot towers designed for the Southwest Windpower Whisper 100 and 200 units (1KW and 2KW). The kits are reasonably priced at $346 and $540 respectively HERE.

    Here are some related vids:
    Whisper tower kit:
    750w Homebrew Gen and tower:
    35' Lattice tower (homemade):
    55' Lattice tower:
    72' Rohn tilt tower:

    Anything anyone can share on this subject? Thanks
  2. windyguru

    windyguru WindyNation Expert

  3. joshua24br

    joshua24br WindyNation Engineer

    I know your posting is a bit old but, If you haven't already figured out a plan for your tower drop me a message. I just built a 45' steel pipe tip up tower and it was simple and easy.
  4. BeachBum

    BeachBum WindyNation Engineer

    I'm interested in your tower design, especially the base. Please send me any information.
    Thanks, BeachBum
  5. joshua24br

    joshua24br WindyNation Engineer

    Our Tower:
    We used two pieces of information:
    2-“A Wind Turbine Recipe Book” by Hugh Piggott

    We combined the information from both of these and did some modifications due to material quality availably locally.

    We had three grades of pipe available (difference was pipe wall thickness), we used the middle grade. Most things we moved up in size due to lack of knowledge about the strength specs.

    We used steel pipe for the tower and base:
    6 meters of 3”
    6 meters of 2.5”
    3 meters of 2.0”
    24” of 1.5” schedule 80 (we brought this from the USA to make sure the WN slip ring and yal bearing fit properly)

    We over lapped the pipe 24” and welded tabs to the outside of the pipes. We welded the pipe closed at the reduction from one size to another. We used the tabs as attachment points for the 8 guy wires.

    We attached another set of tabs below the ark of the turbine blades for the top guy wires and used the 3” to 2.5” tabs for the lower set of guy wires.

    We used the 2.5” to 2.0” tab as the raising and lowing attachment point.

    We have not figured out a perfect winch for raising and lowering. I want it to be manual, simple, locally available, and not complicated.

    Our guy bases are the most over sized. I wanted 48” deep holes. The only digging equipment we had was one shovel with a 36” handle. To get that deep we had the make the hole size bigger and ended up at 24” by 24”. That was 16 cubic feet of cement. We put together rebar cages and used 1/2” rebar for a loop attachment point above the pad level tying into the cages deep into the cement.

    The wire size could have been 3/16”. Again we didn’t know what quality of wire we would be getting and so we used 5/16”. We ordered 600' and had to remake one guy length. We ended with about 60’ extra (I never measured it).

    The tower base and two side bases we made level. The ground was at a slight slope. The upper most pad we made at ground level. The tower base in the middle was 32” above the ground and the lower guy base we had to use a 3” pipe to get up the right height.

    I have posted pictures of all this on the forum. If you want more pictures or info just drop me a note.

    Joshua Bruce
  6. WindyFAQ

    WindyFAQ WindyNation FAQ Staff Member

    I currently have a 42' 4" tilt-able tower, on top I welded a plate, and on top of that a 3" stub of 1 1/2 sch 40. Will that be large enough to take the WN 750 or do I have to modify it?
  7. windyguru

    windyguru WindyNation Expert

    The Windtura 750 complete wind turbine uses a 6 inch piece of 2 inch schedule 80 which is designed to slide over 1.5 inch schedule 80 pipe. At a minimum, you will need a "stub" that is just over 6 inches in length.

    For strength reasons, you really should be using 1.5 inch schedule 80 on your tower instead of schedule 40. But, is you just are putting a ~8 inch stub of schedule 40 to mount the turbine, it should be strong enough (as long as it is welded to a tower that is properly designed.)
  8. Minnesota

    Minnesota WindyNation Engineer

    Anyone know how to figure out the size monopole that can be used for a WN750 (no guy wires). Obviously it varies by height. Maybe streetlamp monopole specs?
  9. leamywind1

    leamywind1 WindyNation Engineer

    If we knew the pounds of wind fource the 750 with 3 blades can handle or lb's/m/s we could match the wind force load to a street pole. I always thought a telegraph pole would be good too. They have no vibration/harmonics to deal with. I do not beleive the WN 750 would snap/bend that. You can find used light poles at many junk yards but most only go up 20-25ft. T-poles are a little harder to find.:)
  10. Minnesota

    Minnesota WindyNation Engineer

    Is a telegraph pole the same as a telephone pole (wood)?
  11. windyguru

    windyguru WindyNation Expert

    We have this calculation somewhere. But I can tell you that the Windtura 750 is not going to ever snap a telephone pole.

    The calculation we did for the Suntura 400 Solar Tracker yielded a result of a 6 inch x 6 inch wooden post and the surface area of the Suntura is ~5800 in^2. Of course the telephone pole is a much longer lever arm but they are like 15 inches in diameter.
  12. leamywind1

    leamywind1 WindyNation Engineer

    Yes, and the diameters do vary on them.
  13. WindyFAQ

    WindyFAQ WindyNation FAQ Staff Member

    Has anyone ever installed onto a retractable pole? Can it be easily brought down in case of a huricane?
  14. windyguru

    windyguru WindyNation Expert

    Most people mount their wind turbine tower with a hinge at the base. Then a gin pole and a winch can be used to raise and lower the tower. If you browse through the tower construction section of this forum, you will be able to find some nice write ups and photos of what I am talking about.
  15. TomT

    TomT WindyNation Engineer

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