Questions addressing small scale power generation

GreenAce92GreenAce92 Registered Users Posts: 17
I am interested in generating my own power, both for future sale of the generator product and also to power my own server for the same website hosting those products.

What I am curious about is raw information.

To give a quick synopsis of myself, I am a physics and engineering student, Junior.
I have taken up to mechanics of materials and up to Quantum Mechanics though I did not complete Quantum Mechanics.
This is *currently* a personal project, not affiliated with the school I attend.

I included this information so that you may not be confused as to why I may be asking mundane questions and yet be addressing advanced topics.

Without further confusion.

I am looking to generate power for small scale. As I said, enough to run a server both during the day and over night with a UPS power supply. Perhaps I will need more to run the computer attached to this server unless I create a hybrid of some sort or a dedicated computer server.

Anyway, one of my questions is, how much power would I need? *Depends on server model and computer model* right but a rough estimate.
I have been told that a single household uses about 8kW's

Secondly, since my application is small, I wondered what is best to use, brushless outrunners (3-phase design) or DC brushed motors

I am a model aircraft guy so I am very familiar with the electronics depicted below. I am not sure if they will suffice my needs for the power generation that I am asking about.
Battery
Motor
ESC ( speed controller to run motor )
Brushed motor DC

Some technical questions
* Is it better to opt for high rpm, or low rpm?
* How can you provide power to something that requires more power than what you generate? Can you trickle charge to build a higher voltage than what the power generator can supply at peak operating performance?
* How do you take the energy produced from an externally rotated motor and "process - store" it?
* If I am going to be transmitting the power generated from the generator to the storage devices by a chord at least 2 - 300' long, should I opt for AC then?
* Are there basic schematics for a circuit that one can build after taking a trip to RadioShack?
* Will the components I listed above work?
* What is the cheapest method to use?

I am limited in size / weight as I am designing my own kite based wind generator
I have seen people that offer this as a commercial service, I have my own design that I'd like to create


I'd really appreciate any help
Regards,



Jacob Cunningham
«1

Comments

  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Questions addressing small scale power generation
    GreenAce92 wrote: »
    I am interested in generating my own power, both for future sale of the generator product and also to power my own server for the same website hosting those products.

    I am looking to generate power for small scale. As I said, enough to run a server both during the day and over night with a UPS power supply. Perhaps I will need more to run the computer attached to this server unless I create a hybrid of some sort or a dedicated computer server.
    I'd really appreciate any help
    Regards,

    Jacob Cunningham

    1. Unless you use a commercial UPS designed specifically for this service, using your UPS every day or night (whenever the wind dies down) on a routine basis will rapidly kill your batteries. Most UPS systems are designed for occasional high demand load from the batteries and may not last beyond ~100 use cycles.
    Instead of a UPS, you will need a standard off-grid battery and inverter setup.

    2. Small wind power is not what you-tube makes it out to be. Do not go deeper without a lot of research about the wind conditions at your site, and with realistic expectations. Apply the part of your physics education that says that the Maximum Theoretical output from wind goes as the cube of the wind speed, and turbines tend to be rated for ~25 MPH wind.

    3. If you have grid power available, none of this makes sense except as a backup for when the grid fails. If you do not have grid power available, you must include a generator in the system and/or really overdesign the power production.

    4. Micro-hydro, on the other hand, can be quite dependable, and solar PV offers better return for the money than small wind.
    SMA SB 3000, old BP panels.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Questions addressing small scale power generation

    Welcome to the forum, Jacob.

    Before you commit financial (or otherwise) suicide I urge you to read through the entire small wind section of the forum. All of it. Note the recurring themes.

    1). Most sites do not have enough actual wind power to make turbines viable, no matter how efficient.
    2). Installing a good turbine in the proper way is not as easy as some would have you believe.
    3). There are a lot of low-quality turbines out there. This is partly due to the high number of scammers and partly due to the fact it is difficult to design and build a good wind turbine.
    4). Wind turbines are more fragile than you think. They need regular maintenance and sometimes break down (or come apart spectacularly) despite this.

    You need to know those things and accept them as fact before you venture down this road.

    I'll try to give you some insight on your specific questions:
    * Is it better to opt for high rpm, or low rpm?

    The terms "high" and "low" are relative. Each has its problems. In the end the amount of wind speed you have available will be the determiner.
    * How can you provide power to something that requires more power than what you generate? Can you trickle charge to build a higher voltage than what the power generator can supply at peak operating performance?

    Power is quantifiable. You can not increase what isn't there. You can up Voltage at the expense of current or vice versa. You can store up power as Watt hours given Watts * time to be expended at a different rate. All these processes will use some of the power potential from the initial generation, resulting in less available power than what you'd have if it could be utilized at the time and rate of generation.
    * How do you take the energy produced from an externally rotated motor and "process - store" it?

    Batteries. They're dreadfully inefficient, but so is everything else. There are different types, some of which are more efficient than others. There are also plans/schemes/scams for storing power in other ways such as hydraulic or compressed air. Same efficiency problems, and usually more.
    * If I am going to be transmitting the power generated from the generator to the storage devices by a chord at least 2 - 300' long, should I opt for AC then?

    Over such distances you should opt for higher Voltage, not necessarily one form of current or the other. However, it is easier to raise AC Voltage than DC as you need only step up with a transformer at one end and step down if necessary with another transformer at the other.
    * Are there basic schematics for a circuit that one can build after taking a trip to RadioShack?

    Basic schematics for what, exactly? There are innumerable schematics for all sorts of things. You can find tons of them on the Internet. That doesn't mean any of them are any good. If you really want to design your own circuits you are in for some intense college education. Electrical engineering is not something you pick up overnight with a couple of clues and good insight. It takes hard work.
    * Will the components I listed above work?

    Possibly, but doubtfully well. In general something designed for one purpose does not work efficiently for another. Motors are meant to provide mechanical force from electricity, not the other way around.
    * What is the cheapest method to use?

    The utility grid. No joke. Self-generated power by any means is far more expensive per Watt hour than any major utility can provide. There are exceptions to this, but they are a matter of specific circumstance.

    Sorry to supply such a depressing response, but that's the way it is.
  • GreenAce92GreenAce92 Registered Users Posts: 17
    Re: Questions addressing small scale power generation

    First I must say that I am on a mobile device currently, and will address what is fresh on the mind. Then later will take notes
    Not saying that any particular response is more important than the other

    Second, aside from the purpose of knowledge acquisition and general curiosity, this was intended in a way as a marketting ploy besides the plain fact that depending on the design's success, it may be profitable.

    I am more of the generator overall design versus the "micro design" so to speak that is, I was most interested in things like depending on the height of an airfoil, how much can I effectively increase wind velocity over the upper surface of that airfoil.

    That's something that I would classify as a "neat experiment"

    Depending on if the Physics club accepts this project or not, I may or may not have sufficient "processing power" to put it in a way, to do the task of bringing this project into reality.

    Now to address some things

    The marketing ploy was to say "This product runs this website"

    I do live on a "power-grid" area, I guess it is hard to compete with the Rankine cycle.

    I live about 2 miles from Lake Erie so wind power is there.

    My design is intended to be air based thereby surpassing the trees
    Also that tells you my limitation on size

    The desin is really quite ingenious in my opinion
    Depending on my level of "It is just an idea" vs. "I don't want people to steal it" or "It already exists" I would love to share with you the design.

    The Earth as I think of it is an infinitely permutative knowledge engine therefore anything one thinks of mist likely has already been thought of by someone else.

    Excuse any spelling error

    Great notes and mind opening on the power supply

    Please don't be concerned about being blunt or "harsh" I want facts not kindness although respect is and professionalism is nice.

    The intention was to operate the server continuously and independently of any other power source.

    Also great tips regarding the components

    More to come when I have access to a larger screen



    Thank you both for your response and also not being a nay sayer
    I would love to read the topics for beginners / information suggested
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Questions addressing small scale power generation

    Probably the best thing you can do to start is buy a Kill-A-Watt meter and find out how much power your server(s) actually use. Figures for activity over at least a week will give you a number on how much power you need to supply. It is much easier to then figure out how to supply it. :D

    If you do come up with a wind turbine design you're happy with remember two things: it will never break the laws of physics (there are plenty of them out there who make such claims without realizing it) and it won't necessarily be suitable for every location. Unlike sunlight which falls fairly steadily the pretty much same everywhere, wind varies a lot from place to place.
  • TheBackRoadsTheBackRoads Solar Expert Posts: 274 ✭✭✭✭✭✭
    Re: Questions addressing small scale power generation

    like this? http://news.cnet.com/8301-11386_3-57405902-76/altaeros-balloon-boosts-wind-turbine-power/
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Questions addressing small scale power generation

    Easier than putting up a tower! :D
    But is it more practical?
  • GreenAce92GreenAce92 Registered Users Posts: 17
    Re: Questions addressing small scale power generation

    OK at the risk of being negatively judged, I will speak my mind

    Also I have decided to just disclose the ideas, whatever I'm not really concerned as I have said before, the idea may already exist
    If not then I am also not concerned if someone else just takes the idea, after all, my mind is also a permutative knowledge engine.
    In fact most cases I can't stop thinking until I pass out from exhaustion. But I like it.

    So I created a name "Normalbus" this is my company which represents me as a person. I plan on using it to sell my products which I design / produce. Previously my main focus was drone/video piloting platforms. Since Normalbus represents the entity of everything I design/dream up, this power generator naturally went towards a product that would be sold under Normalbus.

    Now to the business

    So while sitting in my MicroEconomics class today, I came upon the idea (drifted towards) of a kite based power generator. Let me be the first to admit that this is not a new idea, in fact I saw some company using what appeared to be modified model aircraft if not their own prototypes which were a kite based power generator. Let me also admit that these people are probably much better in designing effectively and efficiently. You'll see what I mean when I disclose my idea

    When I mentioned wind velocity over the upper surface of a wing, my intention was that the power generator was stationary and the wind moved (duh!) but the presence of an airfoil shape in front of the rotating devices would further increase the oncoming wind velocity. Theoretically.

    Now here comes the dumb part. Since my design is based on this, not only will I have extra weight, extra parts, I will also only have an effective working area of half the surface area *disk area* Of the rotating blades / paddles. Paddles? Why yes Watson! Paddles.

    To make sense of what I am describing, below are images.

    Also to further explain my actions. My ultimate goal in life is not to acquire large sums of money, monopolize large firms or lobby ideas that may save humanity for even more profit. My current status is "trying to survive" currently everything I do is funded by myself. So it would be nice if I was established but as I read somewhere a happy income is like 75,000 sure great. My ultimate goal is to leave a legacy, I'm about a fifth of the way of my life (19 almost 20) so... I'd like to help humanity and leave my work behind as proof of my existence.

    Another note, while Normalbus the DNS formally belongs to me, the website does not exist yet, partly because of my own ignorance in the subject but also because it is still in progress of editing. By ignorance I thought DNS marketers also provide webhosting services, hence I am working on creating a power supply to my own server.

    Also note that what I am about to show you below is entirely my own thoughts though I have not checked it against the web, so if this already exists, then I am not correct to claim that it is my work though technically I devised/theorized this idea without external influence.

    My experience on aerodynamics can be found on youtube under two different accounts, GreenAce92 and Normalbus though the Normalbus content is currently private because of the expected existence and professionalism from edited work.

    Now let's work

    To start off, I'd like to show what I meant by increasing wind velocity, this may not be that much of an increase in wind velocity but it is the cause of the rest of my design work. Also this was based on the past knowledge I acquired when designing my own slotted flapperon for my aircraft design Blue Fin

    Initialthoughts_zps97ac7a33.jpg

    Now with this idea in mind, I then proceeded to think about the placement of the rotating devices. Then I pondered about the thought that since the fastest theoretical airflow (my physics may be incorrect) only occurs on half of the trailing wake then only half of the disk area of a rotating blade would be effective. Not to be old fashioned but I thought that a paddle system would be the best at using the most if not all of the energy from the moving wind because the force from the wind would be directly applied to a perpendicular moment arm. See the image below.

    Physics_zpsdb63def1.jpg

    You might think to yourself (besides that this kid is suffering from Delirium) that the paddle idea is dumb, not because of the "propeller is better than paddle" argument but because the retreating blades would cause drag, well a mechanism that makes them parallel with oncoming wind would exist, this is easier said than done but I did consider that part.

    Now how this actually works : An aircraft with vertical take off capability and practically hollow besides the very small battery capacity to go vertical,will carry the chord that attaches this contraption to the ground. A tall tower is created which allows the aircraft 360 degrees of operation without restriction from location / trees. Yes the tower will have to be quite tall. The chord will also need to be specially designed to allow full rotation 360 degrees as the aircraft changes direction due to the wind direction. I also thought about other things such as governors, auto-piloting for correcting the flight path of the drone and feathering main propulsion blade.

    For the sake of showing very very roughly what I envision on doing though as I drew this picture I already noticed changes / flaws
    This image below shows what I intend to do.
    Important notes: Feathering Propeller, Rotating mechanism transfer design to avoid cable carrying design.

    For the aircraft design itself, the object isn't to create the airplane to fly, it is to create the airplane so that the power chord is attached to the body in such a way that when the aircraft takes off vertically ( like a helicopter ) it carries that chord in the center line (Datum?) of the aircraft and when the proper height is achieved, the doors slide open to release that chord and the chord is anchored ahead of the aircraft's proper flying CG position just like a kite.

    So I suppose the wing tips are rounded for looks since that wouldn't be a good thing for 3D design - 3D being the 3D aircraft that fly vertically and have full control.

    RoughAircraftdesign_zps93ffeff5.jpg

    Now for how the generator works, even in a densely "tree-populated" area, one can simply launch the Drone-Generator straight up until the full length of the chord has been taken, then the drone basically faces into the wind and flies like a kite. The feathering main blades are rotated to appropriate positions. Then the flowing air over the wings with the increased velocity will now turn the wheels. Of course the wheels will need to be designed in way that they don't inhibit the climb performance of the aircraft. Something like swiveling them outwards or making them flat in relation to the direction of the aircraft so least amount of drag possible.

    That's more on my behalf though. The purpose of posting here is to gain knowledge on the electronics part as far as power generation, I can design and build this aircraft.

    The launching process in regards to the cord deployment is shown below, this is a key design of the aircraft.

    Doors are closed, aircraft flies vertically until desired height is achieved
    Chorddeployment_zps4f0b6e21.jpg

    Then bays are opened and chord goes into the proper position for kite orientation
    Chorddeployment1_zpsd66616c0.jpg

    I must admit that I based this chord idea with this drone I saw, really a fantastic design. I even had the intentions of contacting them and asking if they could consider trying this idea. I've tried this with certain companies, they really just ignore me for the most part, I'm a nobody!




    After all of this. I think that I will still propose the idea to the physics club people so that I can have real world experience with working in a team environment and seeing a dream become a reality by a whole group, not just by myself. I do that all the time.

    Anyway, so the whole point of this entry was to fully inform you ( the potential answering member ) of what I am trying to do.
    The scale of the aircraft generator can be up to 3m that's something that I can handle.

    I'm just curious if that kind of a size / scale will be enough to do something useful such as powering a server even for a small period of time. Then I can say Normalbus runs on wind generated power during the hours of 4 - 6PM, Normalbus may become unresponsive at times or something like that as a joke.
  • westbranchwestbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Questions addressing small scale power generation

    try this link for Giant Kite info from Victron http://www.victronenergy.com/upload/documents/20100119%20-%20News%20-%20UK%20-%20Giant%20Kites.pdf
     
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    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Questions addressing small scale power generation

    "Whirligig meets magneto". "D

    And you're right, it's not new.

    One problem is the same as for all turbine types: the ideal shape of the blade (whether propeller or paddle) will not be the same in all wind speeds.
    Another problem is that the amount of wind speed necessary to realize any significant power harvest is not going to be suited to the kite design.

    But of course in order to solve problems you first have to know what the problems are, right? So keep on.

    BTW, it is possible to design blades that change shape according to wind speed to increase their viability at different velocities. It is also possible to design electronics for the generator portion to do likewise. The added complexity, however, makes it less practical on a small scale and exacerbates the inevitable maintenance troubles.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Questions addressing small scale power generation

    Someone is bound to point out that you've taken a VAWT with all its inherent problems and turned it 90 degrees, so it may as well be me. :p
  • GreenAce92GreenAce92 Registered Users Posts: 17
    Re: Questions addressing small scale power generation

    Sorry what is "VAWT" ?

    - Google - Hmm I see interesting
    What my design is primarily based on is the concept of increasing relative wind speed by using an airfoil
    I'm not sure if that is also the basis of the VAWT and skipping the kite idea entirely
    The reason I though of paddles is because a blade would not be that effective in taking that theoretical "pure" airflow directly without losing force. A propeller generally tapers due to the concern for centroid "moment of inertia" whether it is mass or the force exerted by the air molecules.

    Also I thought about swept cases , ( wings ) which would direct air to the paddles be it forward swept design ( one paddle in the center ) and rear swept ( two paddles, one at each wing tip )

    Anyway, I have to focus on one project at a time in particular to start producing the Blue Fin

    I figured the most important thing I can get out of this is to have the minds of others working / thinking about the idea and of course figuring out if it is a viable idea or not.

    Not being spiteful but the physics club here sucks, they don't really do anything "cool" so to speak.
    I only thought about them because when I asked a professor about increased velocity and a spinning object only exposed to half of this since the rest could be considered relatively stagnant (not true just generalizing) then how do you create something that would answer that question.

    Anyhow, thank goodness electricity is somewhat cheap

    About the spinning blade design varying to speed, what about a centriful design which changes the shape of the blade based on how fast it is rotating?

    I thought about more particularly a vertically oriented helix type wind turbine but I suppose the simple 2 bladed perpendicularly oriented type ( standard design ) could also use a naturally large blade design until gaining speed.

    Sort of like those F-87 Sabre extending slots that pop out when the plane is flying slow enough

    I appreciate the responses and giving me a chance
    Really means a lot
  • ggunnggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: Questions addressing small scale power generation
    GreenAce92 wrote: »
    Sorry what is "VAWT" ?

    Vertical Axis Wind Turbine.

    There are a bunch of them out there but none really work that I know of. Scam city.
  • ggunnggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: Questions addressing small scale power generation

    First, let me say that I applaud your entrepreneurial spirit. It's guys like you that spark new technologies that change our lives.

    That said, understand that most successful entrepreneurs didn't hit the big time with their first (or maybe even their hundredth) idea. It's not that this idea will change the world; it might, but I sincerely doubt it. The real issue is that as you chase this idea to ground and discover all the things that are wrong with it, you will learn valuable lessons from the experience that will give your *next* Big Idea a little better chance to succeed. Lather, rinse, repeat.

    Full speed ahead!
  • GreenAce92GreenAce92 Registered Users Posts: 17
    Re: Questions addressing small scale power generation

    ggun Thank you for the support

    I had an argument with my mother today about "intrinsic motivation" driving one vs. "the prize" you see... my goal isn't really to make a lot of money (though it would be nice... :) ) but to leave a legacy and to contribute to the Human race! Wow that sounds really sad. I was very moved by the recent news regarding Bill Nye, it is people like himself who need to be around more.

    I have proposed this idea to the physics club member here and they are very intrigued by the proposition, next time I will bring one of my drones which will further spark their interest. They requested something "tangible" so... I figure if I show them some wings, batteries, motors and such... this will further drive their drive

    I understand that the rc equipment is not idea so really it is just to show them that I know what I am doing, at least in the aircraft aspect

    But yes! Indeed. It is exciting to dream of something and then to do it!
    This is a mere toy but I designed this simple wing locking system out of wood, allowing my aircraft to use the same set of wings while flying three different planes! Ah! Awesome.

    Power Generation is not something that is hard (in my opinion) it is merely untouched ground yet... my circuit designing knowledge isn't very good, I've only taken E&M but yeah... anyway
    Indeed, full speed ahead. It would be great if this university funded us ha!



    I didn't mean to indirectly advertise here, I just wanted to show my "thorough" knowledge of the aerodynamics field which I plan on integrating with the power generation in order to achieve a flying based power generator. Yes I am aware that this already exists.
    http://news.nationalgeographic.com/news/energy/2012/09/pictures/120924-flying-wind-turbines/

    However the purpose of my idea addresses two things:

    ** Operation in dense vegetation and dense population (city)
    ** Using airfoils to accelerate the current wind velocity to create more power
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Questions addressing small scale power generation

    I always say "you'll never find a more dense population than in a city." :p

    You might try your airfoil idea on a stationary VAWT first, where you can control conditions and see what makes the best improvement. Along those lines you will have to set up a ground-level lab. You'd be surprised at the number of people who waste a huge amount of time and effort hoisting experimental wind turbines up in to the air - and then wait for enough wind to come along to see if it does anything.

    To that end, turbine designs can easily be bench tested by driving them with a motor (controlled input speed eliminating the wind speed variations). Your design will need air moving over it for testing, and that is going to require a fairly substantial fan (depending on the scale of the prototype).

    Just a suggestion.
  • GreenAce92GreenAce92 Registered Users Posts: 17
    Re: Questions addressing small scale power generation

    It is an excellent suggestion

    I did intend on doing experimenting with ajrfpil heights and increased wind velocity

    I think that the scale will be about 2m and a high aspect design. Thought about evaluating the design with regards to spanwise flow (from swept design)
  • BB.BB. Super Moderators, Administrators Posts: 32,017 admin
    Re: Questions addressing small scale power generation

    Trucks and trailers have been used for a long time to test anything that moves through the air.

    They used to test hang gliders gimbaled on trucks in Half Moon Bay (California) next to a 1 mile frontage road besides the local public airport.

    If you take engineering, there are usually courses on scale modeling for fluid and air flow. It is a very interesting and deeply historical field (how stuff used to be done before computers). Also, you will quickly learn that "boundary conditions" and dramatically affect the results (i.e., placing a wind turbine model in a wind tunnel--if the bladed are too close to the sides of the tunnel, the model starts acting like a ducted fan--which in no way is reproducible in "open field" installations). These links are from www.wind-works.org

    Ducted or Augmented Turbines

    Fantasy Wind Turbines


    One thing that may help you is to find the basic "best case" equations used to estimate airflow/power transfer. Many times, a simple "back of the envelope" calculation can demonstrate if a project is worth going forward or not.

    Betz' law - Wikipedia, the free encyclopedia


    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • ggunnggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: Questions addressing small scale power generation
    GreenAce92 wrote: »
    ...I was very moved by the recent news regarding Bill Nye, it is people like himself who need to be around more. .

    Bill Nye is not dead.

    http://rumorfix.com/2012/08/is-bill-nye-the-science-guy-dead/
  • GreenAce92GreenAce92 Registered Users Posts: 17
    Re: Questions addressing small scale power generation

    ggun, that was not my intention.

    What I mean is, I in particular am surrounded by many people who aren't "educationally backed up" so to speak and yet they feel that by "talking well" they are correct in whatever they are discussing.

    When I watched the news report regarding Bill Nye's views on religion and such, I was basically staring at a mirror. I was awed by the way he thought, I only wish that I was around people like himself more hence I live a good portion of my life on the web where I am connected to people such as Bill Nye who I other wise would not have contact with.

    Further I too am in awe about technology, facts like Space Shuttle engines producings 8 million pounds of thrust and going above mach 25 to break Earth's gravity, shock diamonds, after burners it is all so enthralling and yet not a lot of people are into that stuff it seems so perhaps I need to move somewhere better or probably not have enrolled in a liberal arts school.


    I came back here to post again I had some questions and was looking for suggestions.
    If anybody follows my methods/works and posts in any forums, people may start to form opinions that "I am one of those guys" who just goes around and stirs up ideas but never follows through well... while it is true that I have done this in the past, I am working on changing that. What holds me back is money still one can argue that "you can simply go mow a lawn and there is $15.00 right there!" well I am the other guy who tries to make money through other means.

    I once read somewhere that the richest men in the world get rich by investing, not through hard labor... but investing
    Sounds great however as I have stated before, I would like to contribute to the present times of mankind's existence, yeah that sounds crazy as hell what I just said but just remember that our sun will explode at some given time and that supposedly the universe will collapse in on itself... while I am aware that a human's life is merely a nano second in relation to the life span of the universe if not even smaller, like a "pico-second" not sure if pico is the right word, I think it is femto, anyway... Why does anything that we do matter? Well I suppose it is to stir up those chemicals in our brains that make us happy and feel like everything is ok.

    SO. Back to my purposes

    I wanted to ask what is the best way to store energy. Should I take the energy generated and run compressors to store air pressure energy? Should I raise something and the acceleration of gravity will make power?
    Those ideas sound already like dumb ideas, since they are wasting energy why not simply store the energy in batteries.

    I was curious if it was possible to almost "stasis" energy, that is to say, the time it takes electricity to travel through a wire, what if you can create a nearly infinite lenght of wire in a small space, using technology such as nano-technology and basically have electricity "caught in traveling" and yet somehow you can easily access it when you want to... I suppose that is what a superconductor is... besides no resistance

    Anyway, I had other questions.
    Basically my physics club to put it bluntly is clueless when it comes to this stuff. When I presented I thought people would laugh at me and think my idea was so stupid but nobody seemed to entirely understand what I presented and were simply "awed" at my speech in the sense that it sounded cool. It was surprising that even showing a demonstration of a "winder" lighting up a lightbulb showing EMF in action would still not make a person understand that a motor running backwards is basically a generator. Backwards I mean something else causes the motor to rotate not the rotational force induced by the presence of a magnetic field (feeding the motor power to rotate)

    Anyway, it was mentioned that the motors I posted here were designed "one way" to basically be efficient in converting electrical energy to rotational energy not the other way around... so what motors should I go for?


    I hate to put "filters" on the answers that I expect to receive but I don't exactly want the "direct" answer but ideas towards the right answer as I figure I will assign tasks to individual members / small groups to figure out things like methods of storing energy, how a generator works, wind velocity and blade design etc...

    Only a very few out of the few physics club members are studying to be engineers so not many I would think would know much about properller design

    I also wanted to refer back to another topic mentioning propeller design and efficiency based on speed, does this matter when the propeller is as small as say <12" diameter? For one we haven't really even determined how we plan on generating the power in terms of what will be rotating.

    The basic problem is how to generate power in a place that does not have access to "free air" that is unobstructed air by tall buildings, dense vegation etc...

    That's where the aviation part comes in (me) and then the power generation is a new topic to be studied.

    I had a thought, what if a gear shifting mechanism can switch between a "motor mode" to "generator mode" by sliding a can basically the can would be what housed the magnets and either a bundle of wire would be at the center or more electro magnets so it could be possible to switch from motor mode to generator mode when appropriate.

    I also had an idea for a rotating design in terms of blade design that can vary with speed, basically combining topics with centripetal force or centrifugal (things fling outwards when spinning) not acceleration points inwards, then blades that look like flower petals can fold backwards when reaching high velocity.

    Just speaking out loud here, I'd appreciate any help.

    Thanks
  • GreenAce92GreenAce92 Registered Users Posts: 17
    Re: Questions addressing small scale power generation
    BB. wrote: »
    Trucks and trailers have been used for a long time to test anything that moves through the air.

    They used to test hang gliders gimbaled on trucks in Half Moon Bay (California) next to a 1 mile frontage road besides the local public airport.

    If you take engineering, there are usually courses on scale modeling for fluid and air flow. It is a very interesting and deeply historical field (how stuff used to be done before computers). Also, you will quickly learn that "boundary conditions" and dramatically affect the results (i.e., placing a wind turbine model in a wind tunnel--if the bladed are too close to the sides of the tunnel, the model starts acting like a ducted fan--which in no way is reproducible in "open field" installations). These links are from www.wind-works.org

    Ducted or Augmented Turbines

    Fantasy Wind Turbines


    One thing that may help you is to find the basic "best case" equations used to estimate airflow/power transfer. Many times, a simple "back of the envelope" calculation can demonstrate if a project is worth going forward or not.

    Betz' law - Wikipedia, the free encyclopedia


    -Bill

    Thank you very much!
    This was so helpful!

    In somewhat relevance, I proposed a joke that the team could build cheap windspeed indicators by placing a small propeller on a dc motor and logging the voltage generated while the motor was mounted to a car. It is a joke because it is pointless to do since windspeed indicators are relatively easy to access.

    Thank you for these links!
    Unfortunately I am only in the physics portion of my study, I made an error enrolling in this school and it has only taken me nearly 3 years to realize that.

    In termso fluid flow and scale modeling, there is a youtube channel that shows old documented footage on scale models of aircraft such as the space shuttle, f18 fighter jet, AV8 Harrier etc...

    It is really incredible, here is an example
  • GreenAce92GreenAce92 Registered Users Posts: 17
    Re: Questions addressing small scale power generation

    Bringing back an old thread (oh boy)

    I just wanted to make a note, I mentioned this idea to a friend of mine who studies aerospace engineering, he said that it was dumb because the flow velocity at the end of an airfoil is supposed to be zero (at the point) or trailing edge of an airfoil. So trying to get the "faster moving air" effects from the top of the airfoil by placing a "paddle wheel" behind the airfoil is not really a great way to generate energy.

    Besides, the paddle idea is so much drag... and perhaps it would make the aircraft not able to fly let alone carry the cable which holds it to the ground.

    I haven't actually assessed this idea in depth but it seems to me that you guys were very kind and open minded to me so thank you.

    p.s. I don't have connections with Bill Nye, I don't know why I wrote that in one of my older posts.
    I think what I mean to say was smart people who I would not have contact with in person.
  • BB.BB. Super Moderators, Administrators Posts: 32,017 admin
    Re: Questions addressing small scale power generation

    Welcome back--Hope you are enjoying your classes.

    I am not quite sure what you are trying to say/ask... Trying to generate power from a "kite" like device?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Questions addressing small scale power generation
    GreenAce92 wrote: »
    I was curious if it was possible to almost "stasis" energy, that is to say, the time it takes electricity to travel through a wire, what if you can create a nearly infinite lenght of wire in a small space, using technology such as nano-technology and basically have electricity "caught in traveling" and yet somehow you can easily access it when you want to... I suppose that is what a superconductor is... besides no resistance


    Hi!
    Since you are back, I thought I would reply to the above part of your much earlier post.

    1. This has nothing at all to do with the way a superconductor works, but nothing short of quantum physics really does either. :-)

    2. If you consider the amount of energy that you put into a delay line (which is what you are really talking about), it will not hold very much per unit length and a one foot length corresponds to about one nanosecond in time, so the storage time would not be very great. Storing energy in an electromagnetic field gives very low energy density compared to either chemical or mechanical methods.
    And, as you rightly pointed out, you have the problem of how to get the energy out if you need it sooner than the time it is scheduled to arrive.

    Keep on thinking outside the box, but be prepared to be shot down frequently.

    Clarke's Laws of Prediction, formulated by the great science and science fiction writer Arthur C. Clarke:
    1. When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.
    2. The only way of discovering the limits of the possible is to venture a little way past them into the impossible.
    3. Any sufficiently advanced technology is indistinguishable from magic.

    I am also particularly fond of the logical equivalent restatement of the third law:
    "Any technology which is distinguishable from magic is insufficiently advanced."
    SMA SB 3000, old BP panels.
  • GreenAce92GreenAce92 Registered Users Posts: 17
    Re: Questions addressing small scale power generation

    Well, leave it to me to be terrible at getting a message across.

    To be honest, I believe I was simply asking a lot of background information and on top of that, to see if the "gain" from the supposed faster flowing air over the upper surface of an airfoil could be useful for increasing the air velocity that would hit the blades that turn a generator of some sort.

    Still... when I think about those massive rankine cycle turbines... what is a puny little kite going to produce?

    Anyway, isn't the sun all the energy we need? I am partially aware of the short comings of solar panels but what about producing a medium that absorbs all forms of electro magnetic radiation sort of like a "black tar rectenna device"

    I mentioned this idea before somewhere else probably Yahoo Answers in regards to charging a car battery by using ambient energy both artificial and cosmic (my car battery died) and people said I would produce so little power that it wasn't worth it...

    So I'm actually not really sure what my purpose is. I just get interested in a lot of random subjects like lately I have been studying JAVA and HTML on the side just for personal interest.

    So I think any body's input on my thread here is not worth losing sleep over, I'm just "browsing" I guess is what you would call it.

    I'd like to add something else.

    I believe I picked this up somewhere that generators are designed to output specific frequencies or cycles? As in 60 or 50Hz (Japan)
    So... is electricity formatted then to fit our devices. I mean the answer must be yes... but when comparing electricity like static electricity, electricity from eels, etc... how do they differ?

    I hope these questions are still somehow able to be related to this forum.
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Questions addressing small scale power generation
    GreenAce92 wrote: »
    Anyway, isn't the sun all the energy we need? I am partially aware of the short comings of solar panels but what about producing a medium that absorbs all forms of electro magnetic radiation sort of like a "black tar rectenna device"

    This makes perfect sense in theory, and one of the reasons that conventional PV cells do so poorly is that most of the incoming light energy is at the wrong frequency to be converted or simply goes through and is absorbed at the back without producing any electrical energy. The problem is still in the engineering, and there are some very interesting ideas in the labs that may never lead to anything economically feasible.

    One of the things that I found particularly interesting is the infrared-emitting LED that is more than 100% efficient. That is to say that the light output contains more power than the incoming electrical power can account for. That seemed impossible until I read further and found that the LED also had to be heated far above the ambient temperature and most of the energy in the output infrared beam was coming from that heat. Sort of like the electrical part just caused most of the thermal radiation to be at one frequency instead of over a black body spectrum.
    So the thing was really a heat engine that produced infrared light output!
    SMA SB 3000, old BP panels.
  • GreenAce92GreenAce92 Registered Users Posts: 17
    Re: Questions addressing small scale power generation

    I do have a power generation question

    I "designed" or rather dreamed about this pollution monitoring drone (that's my excuse for it to exist) which many of them would be "dispatched" to random bodies of water, specifically small "inlets/outlets" which would have flowing current.

    These small drones would have onboard floating bouy generators which they could release and generate electricity from the flowing stream to recharge the onboard battery(ies)

    I did a brief test with two DC motors, both were connected via a coupler (pen shaft) and a 1.5 AA battery was connected to one motor while the other was measured for voltage output which was a sad 0.6V

    So... with that brief test, I wonder if my dream can exist or not.

    This was an initial conception but I think spoilers are needed as well as two additional legs.

    2012-11-01164922.jpg

    CAM00077.jpg
  • GreenAce92GreenAce92 Registered Users Posts: 17
    Re: Questions addressing small scale power generation
    inetdog wrote: »
    This makes perfect sense in theory, and one of the reasons that conventional PV cells do so poorly is that most of the incoming light energy is at the wrong frequency to be converted or simply goes through and is absorbed at the back without producing any electrical energy. The problem is still in the engineering, and there are some very interesting ideas in the labs that may never lead to anything economically feasible.

    One of the things that I found particularly interesting is the infrared-emitting LED that is more than 100% efficient. That is to say that the light output contains more power than the incoming electrical power can account for. That seemed impossible until I read further and found that the LED also had to be heated far above the ambient temperature and most of the energy in the output infrared beam was coming from that heat. Sort of like the electrical part just caused most of the thermal radiation to be at one frequency instead of over a black body spectrum.
    So the thing was really a heat engine that produced infrared light output!

    I don't understand? A heat engine?
  • BB.BB. Super Moderators, Administrators Posts: 32,017 admin
    Re: Questions addressing small scale power generation

    Remember that anytime you "extract" energy from a system--There are losses/drag/etc. that make things less efficient. I.e., that plane that may have a 10:1 to 20:1 glide ratio will have a 5:1 or less glide ratio if you attempt to pull "free energy" from the air flow over the wing.

    There are two reasons... One is if you disrupt the air flow across the top surface of the wing, it is no longer an efficient wing. In fact, spoilers work on just that principle. They "rough up" the air flow and allow the plane to "sink" at a much steeper angle of approach.

    Second, if you, for example, put a propeller on the plane and try to drive a generator. Even though the power transfer will be fairly efficient, it is still taking energy from the moving aircraft. When training to fly (decades ago), we were taught to bring the plane near stall to stop the propeller from turning (with engine shut down) to increase the glide range.

    Also, drop down air turbines (Ram Air Turbine or "RAT") are use on many jet aircraft as the last ditch way of supplying enough power for hydraulics/etc. to allow the pilots to ditch/land the plane as safe as possible (controlled descent vs "falling out of the sky"). But you don't see these devices used during normal flight--Way too inefficient. (I had an Air Turbine for my old airplane--no generator on the aircraft motor--Was built in ~1944--but never installed it... Just used a small aircraft transceiver and motorcycle battery for power--worked well enough. Adding a modern solar panel would have been about perfect--this was 30+ years ago. Mine was a much more primitive version of this guy).

    [video]www.youtube.com/watch?v=zx4BeNwQ-b8[/video]

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Questions addressing small scale power generation
    GreenAce92 wrote: »
    I don't understand? A heat engine?

    It takes the heat energy applied to the LED body and converts it to focusable light energy, although at an infrared frequency. It is a heat engine in the sense that it takes thermal energy as an input and outputs energy in a different form. In this particular case it is neither electrical nor mechanical energy, and you may have trouble finding a way to use, but a heat engine it is.
    It also depends on being able to radiate the infrared into a cooler area (cooler in radiation temperature).
    The efficiency in use of the thermal energy is probably really poor too, but you can say that the electrical energy conversion is greater than 100% if you are willing to be awfully misleading.
    I consider it sort of analogous to measuring the energy that goes into the ignition system of a car and saying that the output power is far greater than that. All you have to do is not count the fuel involved!
    SMA SB 3000, old BP panels.
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Questions addressing small scale power generation
    BB. wrote: »
    Also, drop down air turbines (Ram Air Turbine or "RAT") are use on many jet aircraft as the last ditch way of supplying enough power for hydraulics/etc.
    [video]www.youtube.com/watch?v=zx4BeNwQ-b8[/video]

    -Bill
    For most planes up till now, the major form of power used for controls, etc. was hydraulic, so the RAT would be driving a hydraulic pump like the one shown on the A-320 in the video. I guess that if a small amount of electricity was needed, they could use a hydraulically driven generator for that. Or just their NiCd batteries.
    But the Boeing 787 uses electrical energy for almost everything, so the RAT on that aircraft directly drives a generator. (I wonder if Chris Olson knows anything about that unit?)
    SMA SB 3000, old BP panels.
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