Questions tagged [wind-power]
For questions related to power (mechanical or electrical) generated from wind.
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Should I pursue airfoils with higher or lower peaks (I am doing wind power in science olympiad and am designing a mini wind turbine)?
I am a beginner in wind power, but I know the basics.
The Bernoulli effect: Air travelling over the curved edge travels more distance over the same amount of time than the straight side.
Due to this, ...
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Why are wind turbines installed slightly "nose up" as opposed to the blade disk being perpendicular to the ground?
While blasting across the northern French countryside I noticed that the wind turbines along the rail line are installed such that they point slightly "nose-up". I don't have a more ...
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Wind farms that wind up in the wind, and then unwind producing energy when the wind is still
Given the difficulty of producing energy for a region when the wind isn't blowing, why is it not possible to have half of each wind farm producing energy directly, and the other half working to lift a ...
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Wind turbines on high-rise buildings?
Recently, it occured to me that there is a lot of "unused" space on flat-top buildings, and so I wondered, whether it wouldn't be a reasonable ideas to put (vertical) wind turbines on ...
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Viability of bladeless wind power generation
I have recently thought of two designs for bladeless wind power generation;
And
They both essentially ionizes the incoming wind which then passes through a coil, the flow of charged wind particles ...
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Is there a way to 'switch OR engage/disengage' power between two different rotating shafts depending on a set RPM (wind speed)?
I'm a final year mechanical eng student, I'm working on designing a prototype of a 'Hybrid vertical axis wind turbine (VAWT)". This hybrid turbine consists of two types of VAWTs Savonius & ...
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How are a Horizontal Axis Wind Turbine's blades joined to the hub, allowing them to rotate?
I know its a basic question for this site.
But I couldn't find the answer on google so I beseech thee.
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Is standard airfoil theory suitable to VAWT blades?
Let me preface this by saying that I did my research and have r̶e̶a̶d̶ skimmed a lot of papers on new blade profiles for vertical-axis wind turbines (VAWTs).
What I have yet to read about is a blade ...
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Wind generator and heater (high power load) connected directly
I am thinking about the building house heating system like this:
Outside my house I put 12V 1000W wind turbine, for example, like this.
Inside my house I connect directly without any converter/adapter/...
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wingrotor rpm regulation; wind turbine regulation mechanism how it works?
First figure-Fig. 23. Regulating wingrotor, rotating in feeble wind, wingspan fully open.
Second figure-Fig. 24. Regulating wingrotor, rotating in strong wind, wingspan contracting.
...
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Estimating yaw torque and power of HAWTs
I am trying to estimate the amount of torque and power required to rotate a 3 bladed Horizontal Axis Wind Turbine (HAWT) about a vertical axis("yaw" motion). I would like to estimate the ...
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Why not build a wind turbine like a vertical Kaplan turbine?
Vertical Kaplan turbines are often used for hydropower plants. They can have an efficiency of more than 90%.
Why don't we see similar designs for wind power? I mean one could imagine to redirect wind ...
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Expected power increase when replacing old (>20 years) wind turbines [closed]
Plenty of onshore windfarms around the world are reaching the 20-25 year old mark and thus may be on the process of repowering.
Let's say an old wind farm has 10 rotors of 0.5 MW each (total power <...
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Carbon and wind energy [closed]
I am looking for sources on the carbon intensity of wind power.
Concrete doesn't directly emit CO2 but the process to make it does in fact emit it. Because concrete is made of aggregate, which ...
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Why wind turbine dont use high lift coefficient airfoils?
All wind turibne use low lift coefficent airfoils from 1.0 to 1.5.
Why not use high CL airfoils to get maximum torque?
http://airfoiltools.com/airfoil/details?airfoil=s812-nr
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Is the main goal for wind turbines to take maximum energy for a given diameter?
If you increase the number of blades, that will increase torque, for the same RPM you get more power,...simple logic
So why only three blades, is main goal for wind turbine take maximum energy for ...
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Theoretical calculation of blade pitch angle
I would like to start by apologizing for my ignorance, I am sure I am missing something very obvious here.
I am using data for the NREL 5MW reference turbine, and specifically power curve and power ...
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Could the St. Louis Gateway Arch be used as a support structure for a giant vertical axis wind turbine?
I am curious to know if the St. Louis Gateway Arch would be strong enough to act as a support structure for a giant vertical axis wind turbine.
I way I am envisioning this being constructed is that a ...
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Is transmitting windmills' mechanical power to ground level that complex?
Thinking about the complications of building and maintaining turbine rooms installed at high altitudes in horizontal axis wind turbines (plus the difficulties related to it when, for example, a fire ...
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How do 3 blade turbines come so close to the Betz Limit?
I have seen many diagrams (see attached) that indicate that modern 3 blade turbines are nearly 50% efficient, which is about 80% of the Betz limit.
Betz calculated his limit based on a theoretical ...
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Are wind powered drones and platforms possible?
A glider is able to fly unpowered indefinitely so long as it can exploit nearby thermals and the like to stay aloft.
The world record is 3,008km so perhaps there is a practical limit.
I imagine this ...
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Small water pump powered by wind turbine : what type?
I need to aerate a small pond in my garden. I would like to build an autonomous system with a small water pump. The power would come from a small vertical wind turbine I will build. Since my pond is ...
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Weibull distribution Units - ENGIEQSOL
I am using Engineering Equation Solver, and it has been telling me the units of my distribution are inconsistent.
According to a the book I am reading, I think it should be unitless (as it is a ...
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Correct wind Weibull distribution for wind+solar system
I'm trying to forecast the peak power output for a wind + solar system. The solar output as a function of time of day and month can be forecasted easily. I also have the historical wind speed for a ...
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Shadow flicker validation
I am currently trying to validate a shadow flickering algorithm against some data generated by Openwind. The goal of this validation is to have a code that we know that is correct and modify it to ...
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Capacity credit vs capacity factor
What is the difference between capacity factor and capacity credit? I know that capacity factor = annual generation / (installed capacity * 8760) but I don't understand how capacity credit is ...
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Wind turbine that is efficiant from all angles [closed]
What shape propeller with a large surface are, would be best propelled from the wind from behind and from the side as well as the front while facing the sun?
I am thinking a pinwheel, but maybe there ...
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Is a geared motor better for a DIY wind turbine?
I have decent electronic understanding, but I've not much idea about motors.
I plan to make a small wind mill which should be enough to power a couple of LED lights for like an hour every day. I was ...
Ouroboros
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How can I get more power out from a windmill motor?
As far my knowledge a dynamo is a motor which provides electricity when the rotor shaft is rotated. My Question to be brief is if I connect multiple dynamos in a single shaft will I get more current? ...
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Can you channel more air into a nozzle by creating a vortex inside of it?
There are designs for ducting in wind turbines to channel a wider cross section of wind into the rotor area. This is unpractical for structural and economical reasons but does actually increase power ...
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Superimposing a Vector Field onto a Toroid in Matlab
I am a systems and control PhD student in Aerospace Engineering. Currently, I am trying to create a wind shear model of a toroidal thermal "bubble" in Matlab similar to the one in this paper (shown ...
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number of electric vehicles that can be charged with specific amount of energy
I used minutely sampled wind speed data for one year to calculate the yield power from specific wind turbines to be used in electric vehicles charging station.
I am supposed to calculate the number ...
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What is and how do you calculate the wind velocity design for wind turbines?
I am finding it difficult to get consensus on the definition of design wind speed for aeolic turbines.
I thought it was the velocity that corresponds to the maximum power output, but I have already ...
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small gearbox for experimental wind mill
The gear box will have little torque as I am only using a 12 by 18" wing which rotates. The two shafts I am using are 1/4 ", one form the wing and the other going the to pivot for the wing to circle, ...
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Conceiving a wind turbine as a thermodynamic machine
Traditionally, and continuing till the present day, wind turbines are conceived/presented as power plants which harvest the (macroscopic) kinetic energy carried by an externally available airflow, ...
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How to estimate wind generation using power curve?
I am trying to verify windfarmer generation estimates manually. To do so I am trying to manually calculate the estimated energy production (kWh) of a wind turbine. The information I have available is ...
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Wind turbines with down tower power units. Why aren't they more common?
Concerning the big megawatt wind turbines, if there is such a big trouble with gearbox bearings failing much earlier than expected and costly maintanence or replacement of huge gearboxes, what is ...
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Do 3 blade wind turbines generate more power than a 9 blade, all else being equal?
After doing some research, I have come to the realization that 3 blade design horizontal turbines have the greatest maximum coefficient of performance. Most sources seem to agree a Cp of ~0.45 at TSR=...
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In horizontal axis wind turbines, why does axial component of absolute velocity stay constant (wake rotation theory)
I am having hard time understanding how does the axial component stay constant through the rotor. Every resource i look just says it is due to mass conservation but never gives the actual conservation ...
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Can a bridge's towers be used as wind turbines?
I come from a fairly remote island where we need a 150 min ferry ride to reach the mainland.
While the island has few resources that would encourage a government to investigate the possibility of a ...
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Why vertical wind turbine don't be half covered
I think it would be more efficient for a vertical wind turbine to have a covered funnel about half of it
Something like this figure
It would protected the turbine from opposite wind and also ...
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Hybrid Energy Monitoring Systems
I have been doing research on renewable energy systems and I must admit that I am a newbie in this specific area. I have noticed that stand-alone systems have their own specific monitoring system ...
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Is it possible to generate energy from indoor draft by opening windows on opposite sides of the building?
Wind flow always generates naturally when I opening windows on the opposite sides of the building.
Is it possible to put turbine on the way and generate electricity from that?
It could be optimising ...
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How is the Ampyx Power plain generating energy? [closed]
This is what I'm talking about:
Wikipedia
Youtube video 1
Youtube video 2
Official site
Can you please explain me on how this plane is generating energy? Reeling back the aircraft should consume the ...
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what is 1P frequency in rotor (wind turbine)?
In wind turbine, Is the number of revolution taken in 1s is called 1P frequency? If not, is it possible to find the 1P rpm from rpm measured for 1 hour (that is, I have 60 rpm data points from ...
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What determines the cost of the wind turbines?
If there is an 11kW wind turbine, and a 15kW wind turbine. Why is the 15 kw wind turbine more expensive?
I know it seems like a basic question, but what exactly makes it more expensive? Is it only ...
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Wind measure with strain gauge
I'm trying to build my own weatherstation for my home, I want to measure temperature humidity and wind strenght and direction. For the wind I have a question. I want to measure the wind with a ball on ...
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Is it possible to determine tip-speed ratio from rotor geometry?
Let's say I have the geometry of the rotor: the number of blades, the airfoils that make up each blade, their position, chord length and their twist angle. Would it be possible to use this information ...
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Why not design a Wind Turbine like an Anemometer?
Anemometer measures wind speed. It's shaped with little cups---hollow half-spheres. That looks very logical as the cups grab the wind and the other side is rather streamligned to cut through the air ...
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Why isn't it possible to build a car moved by wind power?
So, first of all, I am a High School student and I wanted you to explain me something (in a more "concrete" way, if you know what I mean): I had an idea the other day to make a car with a wind turbine ...
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