Powerful do-it-yourself wind generator for 220v. DIY homemade wind generator for home
Often, owners of private houses have an idea about the implementation backup power systems. The simplest and most affordable way is, of course, or a generator, but many people are turning their eyes to more complex ways of converting the so-called free energy (radiation, energy of flowing water or wind) into.
Each of these methods has its own advantages and disadvantages. If everything is clear with the use of water flow (mini-hydroelectric power station) - this is available only in the immediate vicinity of a fairly fast-flowing river, then sunlight or wind can be used almost everywhere. Both of these methods will have a common disadvantage - if a water turbine can work around the clock, then a solar battery or a wind generator is only effective for a while, which makes it necessary to include batteries in the structure of the home electrical network.
Since the conditions in Russia (short daylight hours for most of the year, frequent precipitation) make the use of solar panels inefficient at their current cost and efficiency, the most profitable is the design of a wind generator. Consider its principle of operation and possible design options.
Since no homemade device is like another, this an article is not a step-by-step instruction, but a description of the basic principles of designing a wind turbine.General principle of operation
The main working body of the wind generator is the blades, which rotate the wind. Depending on the location of the axis of rotation, wind turbines are divided into horizontal and vertical:
- Horizontal wind turbines the most widespread. Their blades have a design similar to an aircraft propeller: in the first approximation, these are plates inclined relative to the plane of rotation, which convert part of the load from wind pressure into rotation. An important feature of a horizontal wind generator is the need to ensure the rotation of the blade assembly in accordance with the direction of the wind, since maximum efficiency is ensured when the direction of the wind is perpendicular to the plane of rotation.
- blades vertical wind generator have a convex-concave shape. Since the streamlining of the convex side is greater than the concave side, such a wind generator always rotates in the same direction, regardless of the direction of the wind, which makes the rotary mechanism unnecessary, unlike horizontal windmills. At the same time, due to the fact that at any time only a part of the blades performs useful work, and the rest only oppose rotation, The efficiency of a vertical windmill is much lower than that of a horizontal one.: if for a three-bladed horizontal wind generator this figure reaches 45%, then for a vertical one it will not exceed 25%.
Since the average wind speed in Russia is low, even a large windmill will rotate quite slowly most of the time. To ensure sufficient power supply, it must be connected to the generator through a step-up gearbox, belt or gear. In a horizontal wind turbine, the blade-gear-generator assembly is mounted on a pivoting head that enables them to follow the direction of the wind. It is important to consider that the swivel head must have a limiter that prevents it from making a full turn, since otherwise the wiring from the generator will be cut off (the option using contact washers that allow the head to rotate freely is more complicated). To ensure rotation, the wind generator is supplemented by a working weather vane directed along the axis of rotation.
The most common blade material is large diameter PVC pipe cut lengthwise. Along the edge, metal plates are riveted to them, welded to the hub of the blade assembly. Drawings of this kind of blades are the most widely distributed on the Internet.
The video tells about a wind generator made by hand
Calculation of a bladed wind generator
Since we have already found out that a horizontal wind generator is much more efficient, we will consider the calculation of its design.
Wind energy can be determined by the formula
P=0.6*S*V³, where S is the area of the circle described by the ends of the propeller blades (sweeping area), expressed in square meters, and V is the estimated wind speed in meters per second. You also need to take into account the efficiency of the windmill itself, which for a three-bladed horizontal circuit will average 40%, as well as the efficiency of the generator set, which at the peak of the current-speed characteristic is 80% for a generator with excitation from permanent magnets and 60% for a generator with excitation winding. On average, another 20% of the power will be consumed by a step-up gearbox (multiplier). Thus, the final calculation of the radius of the windmill (that is, the length of its blade) for a given power of a permanent magnet generator looks like this:
R=√(P/(0.483*V³))
Example: Let's take the required power of the wind power plant as 500 W, and the average wind speed as 2 m/s. Then, according to our formula, we will have to use blades with a length of at least 11 meters. As you can see, even such a small power will require the creation of a wind generator of colossal dimensions. For more or less rational under the conditions of making do-it-yourself structures with a blade length of no more than one and a half meters, the wind generator will be able to produce only 80-90 watts of power even in strong winds.
Not enough power? In fact, everything is somewhat different, since in fact the load of the wind generator is powered by batteries, the windmill only charges them to the best of its ability. Therefore, the power of the wind turbine determines the frequency with which it will be able to supply energy.
Often situations arise when electricity in the nearest transmission line becomes unavailable or unreasonably expensive, and in such cases only a homemade windmill can help out. Let's look at options for autonomous supply of a country house with electricity.
Wind generators - which model is better?
Very often you want to save on electricity or get it where there are no power transmission towers yet. It is also possible that it is simply not possible to connect to this tower due to the lack of free power. In any of these cases, it becomes necessary to find an affordable source of electricity, preferably renewable, that is, without the use of fuel. Therefore, let's forget for a while about the existence of gasoline and diesel generators and try to use the power of the wind to generate electricity.
Windmills have existed for quite a long time, a couple of centuries ago windmills were actively used. Yes, during a calm, such a device is of little use, and during a storm even the most reliable mechanism can fail (at best). But for all its unreliability, a do-it-yourself wind generator for a home is the easiest to make, it is considered the most effective, especially if there is no access to a fast-flowing river to install the wheel. And it should be remembered that the windmill tower should not interfere with neighbors with noise, vibration, or even a cast shadow, according to the rules for building a residential building on the site.
There are only 2 main types of windmills: with a vertical and horizontal axis of rotation. Mills, once used everywhere, were machines whose blades were mounted on a horizontally oriented axis. Also, most windmills today are made according to this principle, since this option provides the greatest efficiency. However, do-it-yourself vertical axis wind turbines for home use the lightest wind that will not move the blades of the propeller models. Light gusts from 1-2 meters per second are enough for them. As for manufacturing, it is much easier to make a vertical windmill that receives wind from any direction.
Generators are also distinguished by the type of blades that both of the above species have. For the most part, the main factor in the division into types is the design: rigid or sail. Already, depending on which option is preferable for a particular model, the material for the manufacture of the blades of the wind flow catcher is selected. It can be plywood, tin or thin sheet steel, plastic, composite - for a light rigid structure, and any flexible but durable material will do for a sailboat, including silk, banner fabric or even a thin tarpaulin.
Differences in the shape of the blades of the generators - comparison of efficiency
The simplest version of the horizontal type is the sail structure, that is, simply the arrangement of the propeller planes at a slight angle to the plane of rotation. Rigid blades will require an accurate calculation of the bending of their surfaces, or it will be necessary to achieve maximum performance empirically. Insufficient curvature of the "wing" will result in a decrease in efficiency due to poor capture of the air flow, and too much curvature itself will create resistance to rotation due to friction against the air.
As for vertical axis generators, their wind catchers come in a wide variety of shapes, and development of new contours and curves is ongoing. The simplest option is with blades in the form of troughs, the so-called Savonius design. Their number is usually made even - 2 or 4. Although it happens more when they make home-made 30 kW multi-bladed vertical wind turbines with additional static screens on the outer ring. These screens direct and concentrate the wind to certain areas of the rotor located inside the ring, where the blades are installed directly. They, depending on the diameter of the base disk, can be read from 8 to 16 pieces.
There are also orthogonal propellers, which are located on vertically mounted axes and rotate in a horizontal plane, but their main drawback is their extremely low efficiency. Also, such generators do not work with weak gusts of wind, a speed of at least 4 meters per second is needed. And the least commonly used models of Dorier windmills, including helicoid, with a helical bend of the blades, arcuate wind traps and a design of the "H" type. They are reliable and effective, but they are difficult to make at home.
Pros and cons of various types - analyze and evaluate
As already mentioned, the performance is much higher for models with a horizontal axis of rotation. However, they need a strong wind, this usually happens at a height of more than 10-15 meters, and it is this length that the mast is installed, which is crowned with a rotary gondola with blades. Another positive quality can be considered the absence of a bending load on the shaft, which occurs in windmills with a vertical axis. The disadvantages include the fact that rotary propeller models have 2 shafts, which means more wear parts and a higher probability of breakage.
As for vertical systems, their advantages and disadvantages depend on the model. For example, Savonius windmills are the simplest and can be made for the home with your own hands, both from a tin can and from a metal or plastic barrel. They start up in the presence of 4 blades from the lightest breath of the wind, especially if high-quality parts are installed, then self-unwinding will occur due to inertia even with a gusty wind. But if there are only 2 or 3 blades, independent rotation is impossible, so they put 2 such modules one on top of the other, placing the wind catchers of each at an angle of 90 degrees relative to the other. The windage of this type is large, and therefore the lateral pressure on the axle is very high during a strong storm.
Orthogonal windmills, in addition to their low power, have a number of disadvantages. Firstly, this is a rather strong vibration due to uneven pressure on different parts of the wing-shaped blade. As a result, a bearing mounted on a vertical shaft quickly deteriorates. In addition, such generators emit a rather strong and unpleasant noise during rotation, and therefore can cause dissatisfaction with neighbors in the nearest areas. Helicoid, if purchased ready-made, factory-assembled, are very expensive, as well as multi-blade designs, which have a very large number of parts.
Any wind generator can be installed in a rotating pipe to increase efficiency.
The principle of operation of windmills - how is the system arranged?
Regardless of the type of windmill, it cannot generate energy by itself, it needs a generator, the rotation of the shaft of which will be provided by the blades. If you have a design with a horizontal axis of rotation, you will need a gearbox to transmit movement to the shaft. Next, a controller is connected, which converts the electricity received on the generator coils into direct current, which then enters the batteries. Next, you can connect an LED light bulb, but if you want to charge a device or connect a laptop, you will also need an inverter that converts the charge stored in the battery into alternating current.
It should be borne in mind that each change in current from alternating to direct, and vice versa, reduces the total amount of energy by 10–15%.
A vertical axis installation is convenient in that its shaft can be quite long, and this allows you to place the generator at the bottom of the mast, that is, in the direct access zone. Often, an automatic switch is installed in the circuit, in cases where the windmill works in combination with solar panels or a water wheel. Also, in some models, they put a brake, which is needed in case the battery is fully charged. Hinges can be provided on the blades of windmills with a horizontal axis of rotation, which fold the wind catchers during a storm. A very powerful do-it-yourself 5 kilowatt wind generator is sometimes supplemented by a rotary electric motor, which is triggered by an air flow direction sensor.
Product on neodymium magnets - brief instructions
It is better to entrust the assembly of the rotor and stator for a windmill to a specialist, but if you decide to make a windmill for a private house from scratch with your own hands, you need to know how the generator is made. You should start with the base, for which it is best to use the hub of the car, since it already has bearings. Neodymium magnets are glued onto the disk at regular intervals, the poles of which, facing you, must alternate. Moreover, in a single-phase model, the number of opposite-pole sides must match. As for three-phase generators, it is recommended to observe proportions of 2:3 or 3:4.
Next, you should start winding the coils for the stator. It is also better to entrust this task to a specialist or use special devices that will help to cope with the task more accurately than if everything is done manually. In order to successfully charge a 12 watt battery, you need a total number of turns in all coils equal to 1000. In general, the simplest formula can be used to calculate the turns ω=44/(T*S), where 44 is a constant factor, T is the Tesla induction, and S is the cross section of the wire in square centimeters. Tesla induction is determined from the table for various types of conductors:
Wound coils (it is better to give them a rectangular or trapezoidal shape for ease of arrangement in a circle) are fixed with glue on a fixed base of the stator. In this case, the shape and dimensions of the internal space of the coil must correspond to the contours of the magnet. The same goes for thickness. We bring out all the ends of the conductors and connect them so that we get two common bundles "+" and "-". We fill the cores of the coils with the same glue that was used for fixing, it is also possible to completely isolate the wires laid on the stator disk with it. Now, if the magnets are combined with the coils during the rotation of the rotor, the potential difference between the poles will create conditions for generating electricity.
Making a windmill based on a finished electric motor
Usually, home craftsmen try to use car generators, but not all are suitable, but only self-excited ones, for example, those used in some tractor models. Most require the presence of a connected battery for the current to appear. However, a motor-wheel for a scooter or scooter can also be used as the basis for a windmill. This will make it possible to make low-noise vertical wind turbines of 5 kW, which will have a very high resource due to the simplest design with a minimum of parts.
You can also use almost any electric motor from household machines as a generator, the main thing is that there are no brushes in the base, as, for example, in or electric drills - such generators will not suit you. A cooler from a computer is also suitable for a low-power version, but only for charging small electronic devices. If you want to get a do-it-yourself vertical wind generator, at least 2 kW, it is better to take the motor from a powerful fan as a basis.
Minerals extracted from the bowels of the earth and used by mankind as energy resources, unfortunately, are not unlimited. Every year their cost increases, which is explained by a decrease in the level of production. An alternative and growing option for energy supply is wind farms for the home. They are allow you to convert wind energy into alternating current, which makes it possible to provide all the needs for electricity of any household appliances. The main advantage of such generators is absolute environmental friendliness, as well as free use of electricity for an unlimited number of years. What other advantages does a wind generator have for a home, as well as the features of its operation, we will analyze further.
Even ancient people noticed that the wind can be an excellent assistant in the implementation of many works. Windmills, which made it possible to turn grain into flour without spending their own strength, became the founders of the first wind turbines.
Wind farms consist of a certain number of generators capable of receiving, converting and storing wind energy into alternating current. They may well provide an entire house with electricity that comes from nowhere.
However, it must be said that equipment and maintenance costs are not always cheaper than the cost of central electricity networks.Advantages and disadvantages
So, before joining the supporters of free energy, you need to realize that wind farms have not only advantages, but also certain disadvantages. On the positive side the use of wind energy in everyday life, the following can be distinguished:
- the method is absolutely environmentally friendly and does not harm the environment;
- simplicity of design;
- ease of operation;
- independence from power grids.
Home mini-generators can either partially provide electricity or become a full-fledged substitute for it, transforming into power plants.
However, one should not forget about limitations, which are:
- high cost of equipment;
- payback comes no earlier than after 5-6 years of use;
- relatively small efficiency factors, which causes power to suffer;
- requires expensive equipment: a battery and a generator, without which the operation of the station is impossible on calm days.
In order not to waste a lot of money, before buying all the necessary equipment, you should evaluate the profitability of the power plant. To do this, calculate the average power of the house (this includes the power of all electrical appliances used), the number of windy days a year, and also evaluate the area where the windmills will be located.
Main structural elements
The simplicity of the construction of the power plant is explained by the primitiveness of the structural elements.
To use wind energy need these details:
- wind blades - capture the wind flow, transferring momentum to the wind generator;
- wind generator and controller - contribute to the conversion of the pulse into direct current;
- battery - stores energy;
- inverter - helps to convert direct current to alternating current.
Since ancient times, mankind has been using the power of the wind for its own purposes. Windmills, sailing ships are familiar to many, they are written about in books and historical films are made. Nowadays, the wind power generator has not lost its relevance, because. with it, you can get free electricity in the country, which can come in handy if the lights turn off. Let's talk about homemade windmills that can be assembled from improvised materials and available parts at a minimum cost. For you, we have provided one detailed instruction with pictures, as well as video ideas for several more assembly options. So, let's look at how to make a wind generator with your own hands at home.
Assembly instructions
There are several types of wind turbines, namely horizontal, vertical and turbine. They have fundamental differences, their pros and cons. However, the principle of operation of all wind turbines is the same - wind energy is converted into electrical energy and accumulated in batteries, and from them it goes to human needs. The most common type is horizontal.
He is familiar and recognizable. The advantage of a horizontal wind generator is a higher efficiency compared to others, since the blades of a windmill are always under the influence of air flow. The disadvantages include a high requirement for wind - it must be stronger than 5 meters per second. This type of windmill is the easiest to make, so home craftsmen often take it as a basis.
If you decide to try your hand at assembling a wind turbine with your own hands, here are a few recommendations.
You need to start with the generator - this is the heart of the system, the design of the screw assembly will depend on its parameters. For this, automobile generators of domestic and foreign production are suitable, there is information about the use of stepper motors from printers or other office equipment. You can also use a bicycle wheel motor to make your own windmill to generate electricity. In general, almost any motor or generator can be used, but it must be tested for efficiency.
Having decided on the energy converter, you need to assemble the gearbox assembly to increase the speed on the generator shaft. One revolution of the propeller should equal 4-5 revolutions on the generator shaft. However, these parameters are selected individually, based on the power and features of your generator and blade assembly. A part from a grinder or a system of belts and rollers can act as a gearbox.
When the gearbox-generator assembly is assembled, they begin to find out its resistance to torque (grams per millimeter). To do this, you need to make a shoulder with a counterweight on the shaft of the future installation, and with the help of a load, find out at what weight the shoulder will go down. Less than 200 grams per meter is considered acceptable. The size of the shoulder in this case is taken as the length of the blade.
Many people think that the more blades, the better. This is not entirely true. We need high speed, and many propellers create more resistance to the wind, since we make them at home, as a result of which at some point the oncoming flow slows down the propeller and the efficiency of the installation drops. You can use a two blade propeller. Such a propeller in a normal wind can spin over 1000 revolutions per minute. You can make the blades of a homemade wind generator from improvised means - from plywood and galvanizing, to plastic from water pipes (as in the photo below). The main condition is that the material must be light and durable.
A light screw will increase the efficiency of the windmill and sensitivity to air flow. Do not forget to balance the air wheel and remove bumps, otherwise, while the generator is running, you will hear howling and howling, and vibrations will lead to rapid wear of parts.
The next important element is the tail. It will keep the wheel in the wind flow, and turn the structure in case of a change in its direction.
To make a current collector or not, it's up to you. This will complicate the design, however, it will save you from frequent twisting of the wire, which is fraught with cable breaks. Of course, in its absence, you will sometimes have to unwind the wire yourself. During the test run of the wind turbine, do not forget about safety, spinning blades are a great danger.
A tuned and balanced windmill is installed on a mast, at least 7 meters high from the ground, fixed with spacer cables. Next, no less important node is the storage battery. The most commonly used car acid battery. It is impossible to connect the output of a homemade wind generator directly to the battery; this must be done through a charging relay or a controller that you can assemble yourself or purchase ready-made.
The principle of operation of the relay is to control the charge and load. In the event of a full battery charge, it switches the generator and battery to load ballast, the system strives to always be charged, preventing overcharging, and does not leave the generator without load. A windmill without load can spin up quite strongly and damage the insulation in the windings by the generated potential. In addition, high speeds can cause mechanical destruction of the elements of the wind generator. Next is a voltage converter from 12 to 220 volts 50 Hz for connecting household appliances.
Now the Internet is full of diagrams and drawings, where craftsmen show how to make a wind generator with powerful magnets on their own. Whether they are as effective as they promise is a moot point. But it's worth trying to assemble a wind power plant for your home, and then decide how to improve it. It is important to gain experience and then you can already aim at a more serious device. The freedom and variety of home-made windmills is so vast, and the element base is diverse that it makes no sense to describe them all, the basic meaning remains the same - the wind flow spins the screw, the gearbox increases the shaft speed, the generator outputs voltage, then the controller keeps the charge level on the battery, and with it is already extracting energy for various needs. Here, according to this principle, you can make a wind generator with your own hands at home. We hope that our detailed instructions with photo examples have explained to you how to make a suitable windmill model for your home or garden. We also recommend that you familiarize yourself with the master classes on assembling a homemade device in video format.
Visual video tutorials
To easily make a wind generator to generate electricity at home, we recommend that you familiarize yourself with ready-made ideas in video examples:
So we have provided all the most simple and affordable ideas for assembling a homemade windmill. As you can see, even a child can easily make some models of devices. There are many other homemade options: on powerful magnets, with complex blades, etc. These designs should be repeated only if you have some experience in this matter, you should start with simple schemes. If you want to make a wind generator so that it works and is used for its intended purpose, follow the instructions provided by us. If you have any questions - leave them in the comments.