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Evaluate Renewable Energy Concept

  1. Mar 10, 2013 #1
    Hello, . .

    I have this concept sketch, of a new configuration from what I have been seeing in,.
    "wave energy", (in this case tide flow force energy), . .

    I believe that generally speaking, as a concept, there seems to be
    Although this is just the water wheel without turbine in place, .

    I'd like your take, . . ?

    Last edited: Mar 10, 2013
  2. jcsd
  3. Mar 10, 2013 #2


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    Very nice animated sketch of a turbine for “(in this case tide flow force energy)”!
    You must know that there are already several functioning installations around the world of this kind of scheme. Please see the below websites:

    This Wiki entry gives a good overview of using the tides to generate electric power:

    This document addresses these questions:
    What are good areas for exploiting tidal energy?
    What is the impact on the environment?
    What are anticipated costs of tidal energy?
    What are some of the devices for tidal energy conversion?

    This is from the U. S. Department of Energy and states:
    “Some of the oldest ocean energy technologies use tidal power. All coastal areas experience two high tides and two low tides over a period of slightly more than 24 hours. For those tidal differences to be harnessed into electricity, the difference between high and low tides must be more than 16 feet (or at least 5 meters). However, there are only about 40 sites on Earth with tidal ranges of this magnitude.
    Currently, there are no tidal power plants in the United States, but conditions are good for tidal power generation in the Pacific Northwest and the Atlantic Northeast regions.”

    Cheers, Bobbywhy
  4. Mar 11, 2013 #3
    Thank you, very interesting, will look into this, . . and hope to offer comment.

    It seems there is very little said about this kind of energy so I assume that there isn't a whole lot of interest in it.

    Meanwhile, may I ask you, . . have you any knowledge of similar idea that would work
    using the means of underwater currents, . .

    In viewing the last site you referenced I see only Tidal Turbines,
    The single thing I recognize is, . you have not referred to the type of energy producer that is used to gain power from tides and is a floating type, . . I have seen this in my past referencing Tidal Energies, , . . therefore I assume that this does not need the deep water mentioned previously. . .

    In any case I do not know the need for such deep water etc.

    I'll continue to look into, .

    Last edited: Mar 11, 2013
  5. Mar 12, 2013 #4
    I am thinking, "Bigger is Better", the waterwheel I have in mind is stationary as supported by foundation post, as seen in the first image of first post in this thread.

    However, the diameter might be changed according to water depths, and therefore possibly longer in length to capture more power.It appears to me that the popular version of wave energy technology is one that is tether while afloat.
    This may work but I don't see it as a better producer than the model I am presenting, which is, "not", "tethered", but anchored to the Ocean floor.

    Generally speaking I have not seen the likes of this type of, "energy producer", as this fact can be important to the designer/inventor, etc.

    Realizing there is quite a bit of math to create R&D progress, I think the concept is worth consideration as an alternative source of energy, and as seen herein is the "Turbine-Power Wheel".
    It can used to harness energy from incoming tides as well as currents both on the surface and sub-aquatic, and many fathoms under the sea where inter-continental currents transverse the globe, anchored to the ocean floor by virtue of the foundation post.

    Water Wheel Concept Envisioned At Low Tide


    In a way this concept is the opposite of the water wheel that was once used to power river boats, instead of energy turning it in the water, the water turns it into energy, with that in mind, my gut feeling tell me it will produce more energy that a turbine powered by a blade in the water, that resembles something like a wind generator.As seen here;

    Last edited: Mar 12, 2013
  6. Mar 13, 2013 #5


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    Regarding the “Turbine Water Wheel” diagram in post number one, and the diagram of a similar mechanism in post number three:

    The cylindrical structure seems to be rotating counter-clockwise (from my viewpoint) and the water current seems to be moving from right to left. If these observations are correct, how does the wheel feel any rotational force at all? On the “upstream” or right side where the moving water first comes in contact it seems it would apply a force to upper half of the wheel in the counter-clockwise direction, as shown. But that same current is acting at the same time on the lower half of the wheel and applying a clockwise force. Would these forces not cancel out, resulting in ZERO rotation? Am I missing something?

    Cheers, Bobbywhy
  7. Mar 13, 2013 #6
    Your design has merit, though I would look into these potential problems; the first sketch appears to have two wheels with cables connecting them together, if so, would they survive the stress? Also the second sketch, if you think upon the engineering here, it is similar to a what you would see on a paddle steamer, this type of design requires a propulsion mechanism to rotate against the resistance of the water, and in doing so provides motion.
  8. Mar 13, 2013 #7
    Also, it is similar to a water-mill, where the effect of cascading water on each blade provides motion as well as dynamic energy. perhaps if you installed it beneath a waterfall you would get year round energy that does not fall victim to a lack of wind or wave.
  9. Mar 13, 2013 #8
    Bobbywhy, I think your right, there is a point of cancellation, it may be possible to design the blade sections to simple fold or collapse like Venetian blinds where they are in the position of negative force. Therefore allowing the force to push against the sectors that are it its path, and are the blades that will allow it to gain momentum, and prevent the negative force from cancellation.

    The drawing is actually not scientifically correct, regarding perpendicularity, haha, (first time I used that word), please forgive me
    for that .
    Last edited: Mar 13, 2013
  10. Mar 13, 2013 #9


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    Underwater turbines exist and they typically look like wind turbines.
  11. Mar 13, 2013 #10
    Yes I know that as I posted a picture post 4, . they do not seem to have virtuous power.

    That is just a "gut feeling".
  12. Mar 13, 2013 #11
    Some important questions to consider:

    1.) How much will it cost?
    2.) What is its expected lifespan?
    3.) How much power can it produce?
  13. Mar 14, 2013 #12
    Hello Prima Terra & Bobbywhy, . .thanks for you feedback, . .
    I am relating to a concept that might oppose the cancellation
    or neutralization from counter force. Such as this;

  14. Mar 14, 2013 #13
    Good questions, . . at this time I really can not answer them, . . .
    but they will get answered if I can pass over the feasibility hurdle.

    That hurdle is if the form of, . . is this a good choice over present technologies.
    In the right place and at the right configuration of dimensions, I am thinking yes,
    I believe the obstacle of negative momentum can be solved, and
    there is no lack of force to turn it, whether it be on the surface, near the surface,
    or under the surface, (wave or current).
    Last edited: Mar 14, 2013
  15. Mar 14, 2013 #14


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  16. Mar 14, 2013 #15
    The possibilities to give the wheel blades a mechanism, . . for maximizing on the water born forces against the wheel that will turn it, . . in my opinion exist and can be illustrated in the absence of demonstration, by the concept of blade extrusion or elevation from the wheel surface as the case may be. There also exist the capacity for the blades to act as flaps, rising and falling in a natural but beneficial way.

  17. Mar 14, 2013 #16
    thank you.
    Actually, My interest is primarily in producing power that can compete with large outputs,
    such as hydro-electric and nuclear. I realize the river generators exist, but here I am dealing with the dynamics of a large wheel encountering negative forces.
  18. Mar 14, 2013 #17


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    A river flow is often stronger than typical tidal flows, so the engineering done in that setting is worth looking at.
  19. Mar 25, 2013 #18
    Concept Improvisation


    Thanks Much for you help !
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