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Wind Turbine in a building?

  1. Jun 9, 2009 #1
    Im new to this forum and wanted to see what you think about my new patent pending design. My concept is...using a 2.5Mw wind turbine, refit 110'L rotor blades with a 10-12' diameter of concave vanes or paddles designed to capture max air thru a forced ducted system that is generated from a large 1,000 HP axiel jet fan (used in coal mine ventilation). The fan is started by a 800kw diesel genset and after wind turbine is at max output (2.5Mw), genset is switched off simultaneously as turbine begins providing power to the fan. This creates a self powered generator. The fan uses approximately 30% of the wind turbine output leaving 70% of excess output.
    Last edited: Jun 9, 2009
  2. jcsd
  3. Jun 9, 2009 #2


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    That seems wasteful. You supply 100% energy, then throw away 70%? Unless you're just trying to siphon energy away from the building's HVAC system...
    Last edited: Jun 10, 2009
  4. Jun 10, 2009 #3
    Sounds like a perpetual energy system to me. I think conservation of energy would disagree with you on this one. An 800kW input can only (at 100% efficiency which is impossible) provide a 800kW output. Wind turbines at best are only 60% efficient meaning you would only get an output equal to 60% (at best) of energy put in by the driving fan. So in your case, in perfect lab conditions, your generator would provide 800kW of power and you would get a maximum of 480kW from the wind turbine.

    So even if initially you got 2.5MW from the wind turbine (which would require the generator giving the fan at least 4.2MW), when you switched the generator off, you would then only have the 2.5MW from the wind turbine to drive the fan, and as such the fan would slow down, causing a reduction in airflaw to the turbine, so then you would only get 60% of that 2.5MW out of the turbine which is 1.5MW, this would then decay continuously by 60% until not enough energy remained to drive the fan. Obviously this example works on the basis that the fan can run at the significantly greater operating speed due to the initial 4.2MW.

    In your situation, the fan (1000HP, whilst driven by the generator) would provide ~750kW of power. This would then result in an optimum output from the wind turbine of ~450kW. This is not enough to drive the fan, let alone give an excess. You could however save fuel on the generator by using the windturbines output of ~450kW fed back to the fan and then adding the extra with a smaller generator/lower output off the original.

    "This creates a self powered generator. The fan uses approximately 30% of the wind turbine output leaving 70% of excess output." That statement alone says perpetual energy to me.

    Or am I not understanding the concept?
    Last edited: Jun 10, 2009
  5. Jun 10, 2009 #4
    I wish I could open a bank account which would do something like this. It would be great to deposit $1000.00, then withdraw $1000.00, then redeposit $300.00 of it, and then, magically, be able to withdraw $1000.00 again despite the fact there's only $300.00 in the account. To be able to do that over and over: magic!
  6. Jun 10, 2009 #5
    Is this with the US Patent Office, or another country? What's the patent number?
  7. Jun 10, 2009 #6
    Does that make a difference? They have loads of patents for various perpetual energy systems, doesn't mean they'll work.
  8. Jun 10, 2009 #7
    There's a difference between having a patent pending and being in a waking dream state. The difference is a patent number. Can you provide me with a patent number for any of these loads of patents?
  9. Jun 10, 2009 #8
    Yes, but they will grant the PN regardless of whether it works or not (or at least they have in the past). However you look at it, any person who believes this could possibly work is in a waking dream state, regardless of whether or not a PN exist. What exactly would you do with the PN anyway?
  10. Jun 10, 2009 #9
    Give me one and I'll show you.
  11. Jun 10, 2009 #10
    I'll be generous, heres two:

    4,151,431 and 5,402,021

    not sure which office they are with but they are for a perpetual energy machine. I just read now they are very careful about granting patents to these machines and those two took lengthy legal battles to get. He has no hope in other words.

    You still haven't answered the question though. What difference does a patent number make in this case? The machine won't work unless the designer is with holding information on circumventing the laws of physics, something I believe would be a lot more valuable and useful than a perpetual energy machine.
  12. Jun 10, 2009 #11
    Very generous. I expected you to fail as I had heard that the USPTO will not issue a patent for perpetual motion machines. I was wrong.
    He already has a patent pending. That means he already has a patent number. I'm still waiting to find out what it is.
  13. Jun 10, 2009 #12


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    I think it's called derivatives trading.
    Unfortunately you have to own the bank to do it, fortunately when it all collapses the government bails you out.
  14. Jun 10, 2009 #13


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    As a note, anyone can get a provisional patent number by applying for a patent, even if it would be something readily rejected.

    Btw, I didn't know perpetual motion was an allowed topic of exposition around these parts.
  15. Jun 10, 2009 #14
    It isn't and should be locked. Although currently discussion is on Patents.

    A patent pending simply means it has been submitted and is being checked.
  16. Jun 10, 2009 #15
    Last edited by a moderator: Apr 24, 2017
  17. Jun 10, 2009 #16


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    Oy. Do you really think you can produce 3 times more energy than what you put into a system? By turning a well designed wind turbine into a Pelton wheel?

    Please lock this thread.
  18. Jun 10, 2009 #17
    A tad abrupt but certainly more to the point than my initial answer.

    Again, Jimmy, number whether application/patent DOES NOT prove it will work and changes nothing. I feel it is pointless to even look up an application given its implausibility.
  19. Jun 10, 2009 #18
    The USPTO is notorious for giving patents for stupid things that don't work. Look at all the patents by Stanly Meyers for example. He even got the US congress to give him funding.


  20. Jun 13, 2009 #19
    Does anyone know what the ft lbs torque rating is at start up and at maximum generator output of a large commercial wind turbine?
  21. Jun 13, 2009 #20
    depends on the size of the wind turbine, they range from 2 - 5MW. The size will play a part in this. You realise we start the 'normal' wind tubines with electric don't you? my electronics lecturer worked on the vertical turbines and proved to us they were more efficicient as they didnt need to be 'aimed' at the wind and didn't require input to start.
  22. Jun 13, 2009 #21
    Lets start with a 2.5Mw turbine. This seems to be the most widely ordered unit today from GE, Clipper and Siemens. They all have a wind cut in speed of 7m/s.
  23. Jun 13, 2009 #22
    Before I continue could I just clarify with you that you understand why your original idea wouldn't work? This is purely so I can convince myself that I will not end up in a contradictory circumstance regarding the OP.
  24. Jun 13, 2009 #23
    If we know the exact amount of torque required to start and also to maintain at full output of the turbine, then we will be able to know exactly what to expect. Otherwise, without those torque ratings, we are simply giving in to what weve always been told...it wont work. By the way, GE and Clipper claims to not know what the torque ratings are citing it to be irrelevant.
  25. Jun 13, 2009 #24
    Right, BigApple2625. If you understand basic laws of thermodynamics you would know that "energy can neither be created nor destroyed.". As such, your wind turbine could at most produce the same amount of power as goes into it. (If the fan gives 800kW then the most you could get is 800kW.). Your solution is ridiculous, and even with the torque figures could never be a self sustaining system. Please DO NOT try to convince otherwise as it just can't happen. FACT. Your wind turbine cannot produce its full 2.5MW capacity as it is only being powered by a 750kW fan.
  26. Jun 13, 2009 #25
    When my system is being used to repower every power plant, large ship, and railroad locomotive around the world, remember that you heard it hear first.
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