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Non Carbon Renewable energy sources

  1. Feb 12, 2007 #1
    Non carbon based Alternative renewable fuel sources..Ideas out side of the Box. #1. WIND POWER using a gigantic wind sock. A Wind Drome. Lets imagine a high tensil lightweight material 1000 feet across and 1000 feet high funneling down to an opening only 10 feet by 10 feet at the small end. ( supported by Helium dirigibles tethered with high strength cables, or towers with guidlines). The first 75 % of the structure would be the fabric the smaller 25% would be rigid with the outlet feeding a high speed turbine to a direct drive non geared Generator. louvers on the ridged structure would control the output of the wind velosity going into the turbine. It would make propeller driven windmills obsolete, because of the friction loss through gearing necessary to turn electrical generators at the speed required to produce power. These Wind Dromes could be located in mountain passes which naturally channel wind, or at locations of known constant wind and wind direction. They could be designed to rotate 45 degrees from center in either direction, left or right. I hear there is research going on right now on this same topic. Can anyone comment or direct me to the proper forum?
    Last edited: Feb 12, 2007
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  3. Feb 12, 2007 #2


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    How much pressure would amount in the neck of one of these funnels? I don't think the pressure would be too high. I mean, this isn't like hydroelectric power where you have heavy water falling vertically, this is wind blown horizontally. I don't think the pressure would be enough. I think whatever pressure could be supplied would limit the size of the turbine, although I don't know what that limit is.
  4. Feb 12, 2007 #3
    In this forum on 1st-23-2005 ed shaw posted a formula that explained the math if you access this site you will see the equation. http;//www.physicsforums.com/showthread.php?t=60763 Basically he determined that a certain sized wind funnel which is explained in his post could generate 10 times the input..ie 15mph in at the mouth of the funnel and 150mph out at the outlet or rear. I became interested in this type of wind channeling in 1972. As a free spirited young man living in Fort Lauderdale, I encountered just such an example of wind dynamics. A tropical storm was going through the Florida Straits and I and a few friends were walking along the Beach sidewalk. We came upon 2 simi high rise condos, (about 14 stories high), the two towers were facing each other on a 30 to 40 degree angle to each other with a pooll in between, (like an open ended wedge or a funnel), with an opening between them of about 30 feet on the street side. Like a funnel with the larger opening towards the ocean. Before we reached the condos in the open area facing the ocean, the winds were probably about 30 to 35 mph blowing directly into the beach. A stiff breeze to be sure but not enough to restrict us from walking. As we walked behind the first condo and came into the gap between the two buildings, the wind blew us to the ground we had to pull ourselves along an iron grill fence to get behind the protection of the second condo. I never forgot that experience..the wind had to be over 70mph to knock us over like it did. Now of course this was a 3 sided funnel there was no top to it, and I am sure a lot of the Mass was escaping upwards where there were no restrictions. Wind dynamics at play. I have been in many hurricaines since then and over 55 mph it is hard to stand up and walk, at 70mph it is almost impossible. So wind can be compressed by it's weight and mass to produce enhanced wind speeds on the small end of a funnel like reciever. I personally experience this wind modification that night in Fort Lauderdale in 1972. I think finding a feasable way to harness and multiply it's forces would be a fantastic way to generate clean readily available energy. The wind mills located on the present day wind farms..have too many moving parts..gearboxes that sapp energy from the friction involved in multiple gearing. The huge Blades have to be geared down to a rotating shaft that has to spin a dynamo at at least 1600 to 1800 Rpms to generate significant electricity. Where as with high wind velocities, a direct turbine with little or no gearing would be more efficient, less moving gears, less friction, more energy to convert to electricity. What do you think? I'll check back in tomorrow.
    Last edited: Feb 12, 2007
  5. Feb 19, 2007 #4
    Build it across a mountain pass. Wind power might work for hydrogen generation. Doesn't have to be consistent or tied to electrical demand.
  6. Feb 19, 2007 #5


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    Problem: Your idea relies on some unphysical fluid mechanics. If you blow air into a funnel, you cannot ignore friction and pressure build-up and assume that if X volume of air enters the funnel at some velocity that the velocity of the air exiting the funnel will scale with the reduction of cross-sectional area. Your funnel will be pressurized by air that is entering and is not allowed to leave due to the restriction, resulting in spill-over at the mouth of the funnel.

    As pointed out in an earlier post, you do not have a sealed, contained system driven by head pressure, as in the case of hydro turbines. Your system is going to be limited by the internal pressures developed in the funnel and the resulting rejection of incoming air.
  7. Feb 19, 2007 #6
    The type of funnel or wind sock I am talking about would be titanic in size. It would be perhaps 1000 ft or higher and just as wide, tethered to radio like towers that are reinforced and held in place with high tinsel guide cables. The wind sock would be made of a light weight fabric laced with kevlar type webbing for strength. Perhaps 3000 feet in length tapering down to and attached to a rigid structure covering the last 25% of the whole funnel. The rigid structure would be built out of strong material and reinforced as the funnel further diminishes in size to the input into the turbine chamber The pressure at the small end of the funnel going into the turbine can be controlled by automated dampers along the semicircle of the rigid portion of the whole accumulator. Pressure transmitters sending signals to a microprocessor that sends an output reflective of deviation from set point to a transducer controlling the movement of pneumatic or hydraulic pistons operating the dampeners. This will allow complete control of velocities. It may also be necessary to use a 2 tier controller with a wind velocity transmitter to provide trim for precise and exact control on the wind input into the receiving end of the turbine. There are other options such as secondary and tertiary turbines to absorb increased volumes allowing for additional energy production. It's a "concept" that can be engineered based upon the scenario I explained that took place during that encounter with the tropical storm between the 2 condos that night in 1972. It was a real experience with real accelerated velocities maximized by the squeezing of wind driven air between 2 fixed structures on a 45 degree angle to each other. Compressed air mass. Wind is energy and when the weight of the air is compressed it results in increased energy. Obviously there will be some spillage at the opening, but what is trapped will be compressed by the the large mass that is captured. As I explained.. someone else did the math stated in my original post. Obviously some people also think this can be accomplished. I am not a mathematician nor a physicist, I am a retired Industrial controls engineer/ automation specialist. The Wright Brothers built bicycles.. but envisioned human flight, (no doubt inspired by Birds in flight), and with their combined mechanical expertise designed the first powered airplane..that achieved flight. I am sure they had to endure the naysayers and the negitivity that surrounds every controversial idea. Had they been working on the mating calls of the Kiwi ,( a bird that does not fly), at Yale or Harvard, flight would not have been an obsession to these pioneers of human flight..... I think it can be done. We have an old saying in engineering..with enough imagination, and sufficient resources..anything can be accomplished. I don't believe Albert Einstein worked on the Manhatten project. He was the prominent Exiled German Jewish Physicist that got Roosevelt's attention to consider building an atomic device, at the request of his colleagues like Edward Teller. Enrico Fermi..split the atom and built the Bomb with Teller and other Physicist. Einstein was a Theorist obsessed with the properties of light. He never built anything except controversy. Physicist today challenge the validity of his theories. His theories, like the funnel, are open ended. They have yet to be proven fully in the context of physical proof.
    Last edited: Feb 19, 2007
  8. Feb 19, 2007 #7
    Hi, I applaude your interest in non-carbon renewable energy.
    Here is an alternative plan: Take a windmill and make loys of compressed air, and store it under ground using the granite below as an high pressure air flask. Use the compressed air to run your car. The French and the Aussies have developed an efficient engine which utilizes highly compressed air.
    Less than 5 minutes to tank up. No polution whatever. Sparkling performance.
    You could drill into the granite for 1000 feet, send down a silicone balloon,
    and under-cut the stone 20 feet below the surface for the assembled stop
    port. There you have an air flask that will endure for many,many years.
    No corrosion. You can do all kinds of things with compressed air.
    In the future, compressed air will become an energy commodity like oil or electricity or gas. And.....it's clean.
    Just a thought.
    Best regards, Dan
  9. Feb 20, 2007 #8
    Any thought on finding or even at this stage in our human history imagining an alternative to fossil fuels is a step in the right direction. By thinking outside the "status quo" box we can explore ideas. Engineering constraints and feasibility will eliminate those ideas that will not provide, at the least, moderate to substantial solutions. However, ideas, no matter how extreme should be considered and examined. We MUST not entrust the future of our Planet to the BIG OIL COMPANIES. The CEO's and accountants of these Corporations will be still counting huge profits while breathing from oxygen mask high up in their Boardrooms, while the public will be gasping for clean air and paying through the nose for polluting energy. I will try to comeback later and talk about..#2..on my list.. GEO THERMAL. With new Drilling technologies, robotics/automation, and High temperature alloys it is now possible to tap into the Earths crust and convert the heat available into Energy. This can be accomplished via naturally generated steam through a water injection, steam return process. Iceland has been doing this for decades. There are many possibilities to cut and run from fossil fuels..Our biggest obstacle is to get Wall Street out of the Government. Thanks for your reply..uhm compressed air..it would have to be staged maybe a 3 stage compressor process. In the oil field they use leached out salt domes to store the Nations strategic oil reserves. Salt deposits Compacted over millions of years, are impervious and rock hard. Only fresh water can dissolve it's solid properties. Later, Koonism
    Last edited: Feb 20, 2007
  10. Feb 28, 2007 #9
    How about using the excess spring runoff of the Columbia River to generate power (by building extra power houses at the already existing dams) and using that power to make H2 and putting that H2 in the Salt Domes for later use? We could use the existant Natural Gas pipeline system to move the H2 and fuel cells to burn it.
  11. Feb 28, 2007 #10
    If you could add more generating capacity at the dam, you'd be better off just adding it to the grid and reducing the load on the fossil fuel fired plants.

    Eventually, hydro power may come up against a problem anyway, if the ice fields on the mountains continue to shrink. Those ice fields are part of the summer source of our rivers. In some areas they comprise a lot of it. Wind, we will always have, although taming it isn't easy.
  12. Mar 1, 2007 #11
    The reason why just adding it to the grid doesn't work is that the electricity is intermittent. It is available only in the Spring and at night. That is fine for the part time generation of H2, but the utilities don't want to build two power plants to generate a given amount of power.

    The melting ice fields are a problem though....
  13. Mar 3, 2007 #12
    But Carbon Dioxide (CO2) is an inert gas ...
  14. Mar 4, 2007 #13
    I doesn't matter that the power is intermittent. Thermal power plants exist because hydroelectric sources don't produce enough power to meet our needs. Well, it could be argued that we just waste too much, but that's another arguement!
    Generally speaking, fuel-fired plants supply the "swings" in demand, but they are in service even when demand is at its lowest. So if you can produce more at the dam, even seasonally, you will burn less fuel in the thermo plants.
    The limiting factor for a hydro station is not the size or number of turbines, but the flow of water into the reservoir. I believe that reservoir levels are allowed to fluctuate in order to make the best use of the average flow. If there is an overabundance of water in the wet season, I still don't see an advantage in using the extra generating capacity for electrolysis. In all likelihood, most reservoirs are probably being used to capacity anyway.
    Disclaimer: I do not work in hydroelectric generation, so my opinion is that and nothing more.
  15. Mar 16, 2007 #14
    Actually it is normally the other way around. The thermal plants are difficult to turn off and on so they are run at a level rate while hydro plants are very easy to turn on and off so they are used for peak power. During the night when demand is low, the thermal plants supply all the power needed by the grid so any flow over the dams (for instance to keep water in the river bed for navigation) is wasted.

    What I am saying is that we can use that wasted power (which is very great in the Columbia) to generate a large percentage of the H2 we would need to drive our cars.
  16. Mar 17, 2007 #15
  17. Mar 17, 2007 #16


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    It depends on the type of thermal plant. In the US, quite a bit of our variable load is generated by gas turbine engines, which are very easy to throttle.
  18. Mar 18, 2007 #17
    If you look around the Northwest (say state of Washington) there are a lot of small rivers with warning signs that go something like this:

    "WARNING! River may fluctuate in level very rapidly."

    That is because the hydro power is used for peaking. In these cases, the excess water is not spilled. In the Columbia River though, the river bed needs to be kept at a predictable level. This requires spilling of water and yes it is wasteful.

    I am not sure why large thermal plants have the restrictions they do (I'm an electro optical engineer, not a power plant operator), but it probably has something to do with the thermal inerta of such a large plant. It would simply take too long to start up and to cool down. Hydro on the other hand can be switched in an instant (hence the signs above).
  19. Mar 19, 2007 #18

    The limitation is probably in the turbines, rather than in the steam generation. Reaction turbines for constant load are designed with minimal clearances for the rotor blades. They don't tolerate rapid load changes because the temperature differential between rotor and casing must always stay within tolerance. Consider a spinning rotor, transferring as much power as a large city consumes. Now imagine the blades contacting the stationary guides because of thermal expansion. Not pretty.

    The trade off, of course, is that higher efficiency requires tight clearances, so the ability to accomodate load swings comes at a price.

    As to steam generation: Some large power boilers operate above 3200 psi, the pressure at which the density of the steam equals that of the water. Or to put it another way, steam bubbles can not form. Those conditions make for better fuel efficiency but I know absolutely nothing of the operating requirements. Our boilers operate at a mere 700 psi, and we can increase or decrease the steaming rate as needed. Our turbine is also designed to accomodate load changes.

    BTW Gas turbines in power generation are usually part of a "combined cycle" plant in which the exhaust gases are fed into a conventional boiler which in turn drives a steam turbine. This is a very efficient cycle.

    Now you've made me realize I need to know more! I should be able to find up-to-date information on these questions. Most of my information is "textbook", from courses.
  20. Mar 23, 2007 #19


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    The ideas of using non carbon fuel is great but I think it's over played. Co2 is a greenhouse gas but our effect on global warming is very much likley overplayed. The news media has found that if you tell a lie enough eventually everyone will believe it. The true research doesn't agree with what we hear on TV. The political left would have all of us buy into it in order to control us. Just like with DDT, CFC's and other of their supossed ideas to protect the environment. I'll leave you with a link to a report by an Intellecast scientific group everyone should read. There's plenty of lies uncovered by it. If you really want to know the whole truth read this:


  21. Mar 23, 2007 #20
    The main issue on Global Warming is not on whether it is happening or not, but rather on whether humans cause it. The jury is still out on that one. Afterall temps have swung back and forth quite a bit in the last few million years.

    However the jury is not out on DDT. The experimental evidence for egg shell thinning by DDT is overwhelming. Saying that DDT does not affect birds is like claiming that the Earth is flat. Some people believe it, but the evidence is overwhelming that the Earth is round regardless of what those people think.
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