Ecology of consumption. Science and technology: Do-it-yourself home hydro generators are comparable in power to solar panels and wind turbines, but produce a much larger volume of electricity.
Since electricity tariffs have recently begun to rise, renewable sources of electricity are becoming increasingly important among the population, allowing them to receive electricity almost free of charge. Among such sources known to mankind, it is worth highlighting solar panels, wind generators, and home hydroelectric power plants. But the latter are quite complex, because they have to work in very aggressive conditions. Although this does not mean that it is impossible to build a mini-hydroelectric power station with your own hands.
To do everything correctly and efficiently, the main thing is to choose the right materials. They must ensure maximum durability of the station. Do-it-yourself home hydro generators, whose power is comparable to that of solar panels and wind turbines, can produce a much larger amount of energy. But although a lot depends on the materials, everything does not end there.
VARIETIES OF MINI HYDRO POWER PLANTS
There are a large number of different variations of mini-hydroelectric power stations, each of which has its own advantages, features and disadvantages. The following types of these devices are distinguished:
- garland;
- propeller;
- Daria rotor;
- water wheel with blades.
A garland hydroelectric power station consists of a cable on which rotors are attached. Such a cable is pulled across the river and immersed in water. The flow of water in the river begins to rotate the rotors, which in turn rotate the cable, at one end of which there is a bearing, and at the other - a generator.
The next type is a water wheel with blades. It is installed perpendicular to the water surface, submerging less than half. As the flow of water acts on the wheel, it rotates and causes the generator for the mini-hydroelectric power station on which this wheel is attached to rotate.
As for the propeller hydroelectric power station, it is a wind turbine located under water with a vertical rotor. The width of the blades of such a windmill does not exceed 2 centimeters. This width is enough for water, because it is this rating that allows you to produce the maximum amount of electricity with minimal resistance. True, this width is optimal only for flow speeds up to 2 meters per second.
As for other conditions, the parameters of the rotor blades are calculated separately. And the Darrieus rotor is a vertically positioned rotor that operates on the principle of differential pressure. Everything happens similarly with an airplane wing, which is affected by lift.
ADVANTAGES AND DISADVANTAGES
If we consider a garland hydroelectric power station, then it has a number of obvious shortcomings. Firstly, the long cable used in the design poses a danger to others. Rotors hidden under water also pose a great danger. Well, in addition, it is worth noting the low efficiency indicators and high material consumption.
As for the disadvantages of the Darrieus rotor, in order for the device to start generating electricity, it must first be spun up. True, in this case, power is taken directly above the water, so no matter how the water flow changes, the generator will generate electricity.
All of the above are factors that make hydraulic turbines for mini-hydroelectric power plants and water wheels more popular. If we consider the manual construction of such devices, they are not so complicated. And in addition, when minimum costs such mini-hydroelectric power plants are capable of producing maximum efficiency indicators. So the criteria for popularity are obvious.
WHERE TO START CONSTRUCTION
The construction of a mini-hydroelectric power station with your own hands should begin with measuring the speed indicators of river flows. This is done very simply: just mark a distance of 10 meters upstream, pick up a stopwatch, throw a chip into the water, and note the time it takes for it to cover the measured distance.
Ultimately, if you divide 10 meters by the number of seconds taken, you get the speed of the river in meters per second. It is worth considering that there is no point in building mini-hydroelectric power stations in places where the flow speed does not exceed 1 m/s.
If you need to figure out how mini-hydroelectric power stations are made in areas where the river speed is low, then you can try to increase the flow by organizing a height difference. This can be done through installation drain pipe into the pond. In this case, the diameter of the pipe will directly affect the speed of water flow. The smaller the diameter, the faster the flow.
This approach makes it possible to organize a mini-hydroelectric power station even if there is a small stream passing near the house. That is, a collapsible dam is organized on it, below which a mini-hydroelectric power station is installed directly to power the house and household appliances. published
A mini hydroelectric power station is a small hydroelectric power station that produces a small amount of electrical energy.
Operating principle of mini hydroelectric power station
The operating principle of small hydroelectric power plants is no different from the operating principle of large power stations. The water of a water formation, river, lake, reservoir, under the influence of pressure created by its mass, moves in a given direction and enters the blades of a hydraulic turbine. The turbine transmits its rotational motion to the rotational motion of a generator, which produces electric current.
Water pressure is created by building a dam or by the natural flow of water, or both.
Device classification
Hydroelectric power plants generating power up to 5.0 MW are considered small.
Existing small hydroelectric power plants are classified according to:
1. Operating principle
- Using a “water wheel” - in this case, the receiving wheel is placed in the aquatic environment parallel to the surface of the water, but is only partially submerged. The water masses, exerting pressure on the wheel blades, cause it to rotate, which is transmitted to the rotational movement of the generator.
- Garland design - in this version of the device, a cable is laid from opposite sides, onto which the rotors are rigidly attached. Masses of water moving progressively rotate the rotors. The rotational motion of the rotors is transmitted to the cable, which, in turn, rotates and transmits its rotational motion to the rotational motion of the generator. The generator is installed on shore.
- With a Darrieus rotor - the basis for the operation of devices of this type is the pressure difference on the rotor blades. The pressure difference is created by water flowing over the complex surfaces of the rotor.
- With a propeller - the principle of operation is similar to operation wind generator, with the difference that in the case of a mini hydroelectric power station the blades are placed in an aquatic environment.
2. Application possibilities
- Industrial use (180 kW and above) - used for power supply to enterprises or sales to consumers.
- Commercial use (up to 180 kW) - used for power supply to small energy-intensive enterprises and groups of houses.
- Household use (up to 15 kW) - used for power supply individual houses and small objects.
3. According to the turbine design
- Axial - in units of this design, water moves along the axis of the turbine and hits the blades, which begin to rotate.
- Radial-axial - in this design, water initially moves radially in relation to the axis of the turbine, and then in accordance with the axis of its rotation.
- Bucket - water enters the surface of the bucket (blade) through nozzles, thanks to which the speed of the water increases, it hits the turbine blade, the turbine rotates, the next blade comes into operation and the process continues
- Rotary-blade - the blades rotate around their axis simultaneously with the rotation of the turbine.
4. According to installation conditions
Pros and cons of the device
The benefits of use include:
- Environmental safety of installations for the environment;
- An inexhaustible source of energy;
- Low cost of generated energy;
- Autonomy of installations;
- Reliability of installations;
- Long service life.
Disadvantages of use include:
- Potential danger to inhabitants of water bodies;
- Limited possibility of installation conditions of the installation.
Manufacturers of plants and equipment
A limited number of enterprises both in our country and abroad are engaged in the production of equipment for mini hydroelectric power stations. This is explained by the limited use of small hydroelectric power plants due to the small availability of necessary water bodies, as well as trends in energy development in different countries.
Of the foreign companies successfully operating in this area of business, these are
- "CINK Hydro-Energy" Czech Republic - carries out the full range of work from design and supply of equipment to installation and commissioning of installations.
- "Micro hydro power" China - produces and sells equipment sets for small installations for domestic use.
- Engineering and technical firm "Gidroponics" LLC, Bishkek, Kyrgyzstan. The company produces and sells hydrogenerators for small hydroelectric power plants.
In Russia they work in this market
- AEnergy LLC, Moscow. The company is engaged in development support alternative sources energy. In the field of small hydropower, the company offers a full range of services from design to service completed installations.
- Interindustry scientific and technical association "MNTO INSET", St. Petersburg. The company is engaged in the design and development of equipment for mini hydroelectric power stations, manufacturing and installation of its products. The product line includes:
- Mini hydroelectric power station with a propeller impeller, power from 5.0 to 100 kW;
- Mini hydroelectric power station with a diagonal impeller, power 20.0 kW;
- Mini hydroelectric power station with a bucket impeller with a power of up to 180 kW;
- Hydraulic units for small hydroelectric power plants.
- Company "NPO Inversiya" Yekaterinburg. The company produces equipment and kits for mini hydroelectric power plants with a power of up to 10 kW.
Do-it-yourself mini hydroelectric power station
In order to make it yourself, you need ingenuity, the ability to work with your hands and a water body, 
and some small things, such as a car generator, a wheel from any vehicle and a transmission mechanism (pulleys, gears, gears).
First you need to make a water wheel. To do this, take a wheel from a bicycle, motorcycle or car. The blades are attached along the diameter of the wheel; for this you can use any material, as long as it is durable and does not bend - iron, plywood, hard plastic, ebonite, etc. Best to mount bolted connection so that it is possible to replace blades damaged during operation. The blades are located at an equal distance from each other. 
A frame is made on which the wheel is mounted. At the points of attachment to the frame, it is necessary to provide for the installation of bearings into which the wheel rotation axis is inserted. A large pulley or a large sprocket is mounted on one end of the axle. A small pulley or smaller sprocket is mounted on the generator axle.
Option for a homemade mini hydroelectric power station with vertical wheel installation
The wheel is placed in water, it can be vertical installation in a plane perpendicular to the surface of the water, or horizontal - when the wheel is completely immersed in water. In the second case, it is necessary to take into account that the wheel should be immersed in water no more than 2/3 of the thickness of the disk.
The pulleys are connected to each other by a belt, and the sprockets by a chain.
The system is ready for use.
An independent source of electricity in a country mansion is the first necessity. The electrical goods market offers a wide range of generators electric current various designs: gas, inverter, gasoline, diesel. Among them, water electric generators occupy a special place due to their advantages and savings in fuel consumption. Generating electricity from natural sources is the most environmentally friendly and low-cost way to produce an energy resource.
Scope and features of the device
Various Applications
Data hydraulic devices can be used for various household and household needs:
- In agriculture;
- Towns of geologists;
- In river transport;
- At recreation centers;
- In the mining industry;
- In country and suburban areas.
To convert various types of energy into electrical energy. The structure of the device is simple: the engine, the generator itself and the housing.
Let's watch the video, the scope of application of generator sets and their types:
Depending on the type of power plant, generators are divided into:
There are also water-based and solar powered. A water electric generator differs from a diesel or gasoline generator by being more economical to operate and completely environmentally friendly. If a river or stream flows next to a country house, the amount spent on servicing the station is zero.
Principle of operation
Energy production through rotation structural element has been used for a long time, just remember water mills. A water generator for producing electrical energy differs little from ancient devices.
Let's watch the video, simplest mechanism works:
You need to connect the device hose to a water source (stream, water tap, shower stall tank), and the rotation of the wheel blades under the pressure of water will transfer energy to the generator itself. In turn, the generator will process the received energy into a current of the appropriate frequency (alternating or direct).
Types of hydro generators
Industrial products differ in the parameters of the power they produce. For household needs they use low-power hydraulic systems (10-100 kW) with a vertical position of the rotor axis of rotation, operating on the basis of small watercourses. For industrial needs, devices are designed with horizontal rotational movement of the axis.
Water wheel
For domestic purposes, a damless type of mini-hydroelectric power station is used, which is divided into 4 types:
- Water wheel;
- Garland hydroelectric power station;
- Daria rotor;
- Propeller.
A water wheel is a rotating element with blades, which is installed perpendicular to the movement of water, immersing half or a little less. Through water pressure on the blades, the wheel rotates and energy is converted.
The design of the garland for a water generator is a cable with fixed rotors, thrown from one bank to the other bank of the river. One end of the cable is attached to the generator, and the other is secured by a bearing. Rotors immersed in water begin to rotate under the pressure of the flow, causing the cable to rotate. As a result, electricity is generated.
Rotor Daria
The Darrieus rotor is a vertical rotating element that is driven by changing pressures on the blades complex design. It is the flow around a complex surface that creates a pressure difference.
A water propeller generator resembles a “windmill” equipped with a rotor, but installed under water. The width of the blades (2 cm) has required dimensions for creating maximum speed rotation at minimal resistance load. However, the size of the blades must be selected in accordance with the flow of the water flow; their performance may vary.
In everyday life, propeller-type hydraulic installations and wheels have become widespread. The advantage of these devices is high efficiency with minimal costs.
Product Overview
Manufacturers produce mini hydroelectric power stations household use for generating current of constant and variable frequency in three-phase and single-phase versions. To generate electricity, a small water pressure is required - up to 12 l/sec. As a rule, these hydraulic installations are used in places with small rivers or in areas with a natural/artificial waterfall, as well as a constructed dam.
Mini generator Ct-02 (China)
- Power - 5 kW;
- Generated current - 50 Hz;
- Rotation speed - 30-3000 rpm;
- Current is alternating.
Products can be purchased to order, indicating required parameters. Starting price - 30,000 rubles.
Mini generator for home xj13 (China)
- Power - 8.5 kW;
- Generated current - 50 Hz;
- Rotation speed - 145-1920 rpm;
- Current is alternating.
This model horizontal installation has its advantages, low weight and small volumes. The device can be easily installed in personal plot. Price - from 16,000 rubles.
Hydrogenerator LPWG
Hydrogenerator LPWG
- Power - 5 kW;
- Generated current - 50 Hz;
- Rotation speed - 500 rpm;
- Current is alternating.
This hydraulic system with horizontal water supply will provide electricity to household farms or Vacation home. The purchase of a water electric current generator will cost 49,596 rubles.
How to make a hydroelectric power station yourself
Creating a water electric generator with your own hands is a fascinating process. Can be designed based on a regular bicycle generator. First, you should determine the speed of the water flow using a stopwatch. If the speed is insufficient, you will have to create a height difference, for example, by installing a drain pipe.
Watch the video and do it yourself step by step:
You need to cut from aluminum sheet several blades 2-4 cm wide. The length of the blades should match the diameter of the bicycle wheel (from the rim to the hub). The blades are then installed between the spokes and secured with pliers. The wheel is immersed in water by a third. A very good option for generating electricity while camping for lighting a tent and charging phones.
Choosing an electric generator
Power
- To continuously provide energy to private country house A power of 20-30 kW is quite enough.
- To accurately determine the required power, you need to add up the power consumption of all household appliances and add lighting lamps.
- It should be borne in mind that another 20 percent must be added to the total amount of power, taking into account the starting currents.
- If you work with electrical appliances construction purposes, the required power should be three times greater (up to 100 kW).
Prices and manufacturers
The goods market is provided by various suppliers and manufacturing companies. The price factor is formed depending on the promotion of the brand. Recently, Chinese manufacturers have proven themselves well. The favorable combination of quality and price deserves attention.
First, let's define the operating principle and types of small hydroelectric power plants. The flow of a river or a falling water stream rotates the turbine blades and a hydraulic pipeline, which is connected to an electric generator - the latter generates electricity. Modern compact hydroelectric power plants have automatic control with the ability to instantly switch to manual mode in case of emergency. The designs of modern factory hydroelectric power plants allow production to be minimized construction work when installing equipment.
Types of mini hydroelectric power plants
Mini power plants include generating devices with a capacity from 1 to 3000 kW. Fundamentally, the thermal power plant consists of:
- turbines (water intake device);
- generating block;
- control systems.
According to the type of water resources used for generation, mini hydroelectric power stations are:
- Channel rivers. Such stations are built on small lowland rivers with reservoirs.
- Mountain. Stationary stations that use the energy of fast mountain currents.
- Industrial. Stations that use differences in water flow at industrial enterprises.
- Mobile. Stations using reinforced hoses for water flow.
Dam types of stations are characterized by high power, but the construction of a dam is expensive, and in this case it is impossible to do without permits. To get involved with officials in our country is not just to complicate your life, but to call into question the implementation of the most good intentions, so let’s abandon this idea right away.
How does a mini hydroelectric power station work?
The principle diagram of the operation of a hydroelectric power station can be chosen from several options:
- Garland hydroelectric power station. From one bank of the river to the other, a cable with rotors strung on it is laid under water. The current rotates the rotors and, accordingly, the cable itself. One end of the cable is in a bearing, the other is connected to the generator.
- Propeller. An underwater structure resembling a wind turbine with narrow blades and a vertical rotor. A blade with a width of only 20 mm at a high rotation speed will provide minimal resistance. A blade of this width is selected at a flow speed of 0.8–2.0 m per second.
- Water wheel. A wheel with blades, partially submerged in the flow, and located at right angles to the surface of the water. The flow of water presses on the blades, rotating the wheel.
- Rotor Daria. Vertical rotor with complex blade surfaces. The liquid flowing around the blades creates different pressures, causing rotation.
The photo shows a mini hydroelectric power station based on a water wheel
How to estimate the potential capacity of mini hydroelectric power stations
Before building a mini hydroelectric power station with your own hands, you need to determine the power you can count on. There is a reference relationship between the speed of water flow and the power that can be removed from the shaft in kW with a screw diameter of 1 m.
The speed of the flow is determined by measuring the time it takes for a chip thrown into water to travel a certain distance. Having made simple calculations, we obtain the flow speed in meters per second. If in in this case speed is less than 1 m/sec, then the construction of a hydroelectric power station will not be economically feasible.
At a flow speed of 2.5 m/s, the power will be 0.86 kW, at 3 m/s - 1.24 kW, at 4 m/s - 2.2 kW. The relationship is described by the dependence: the power of a hydroelectric power station is proportional to the cube of the water flow velocity. If the flow velocity at the proposed construction site is low, you can try to increase it by installing a difference in flow heights or by installing a drain pipe with a variable diameter at the outlet of the reservoir. The smaller the outlet diameter of the pipe, the higher the flow rate.
How to make a mini hydroelectric power station at home
The operating principle of a small homemade hydroelectric power station can be understood using the example of a bicycle with a headlight and a dynamo (generator).
- We make three long blades from roofing iron, equal to the radius bicycle wheel (distance from the central hub to the wheel rim) and a width of 3-4 cm.
- We install the blades between the spokes of the wheel, bending the edge of the blade around the spokes to secure it. The blades should be aligned evenly while maintaining the same angles between them.
- We immerse the wheel with blades in a fast river to a depth of one third to half the diameter of the wheel. The generated electricity will be enough, for example, to light a tent.
Drawing of one of the options for constructing a mini hydroelectric power station
An example would be a small hydroelectric power station for farm power 3-5 kW from scrap materials:
- The rotor can be made from an old metal cable drum with a diameter of 2.2 m. Using a grinder and welding at an angle of 45 degrees to the radius, 18 blades need to be welded. The rotor rotates on bearings. Support – metal pipe or angle.
- On the rotor you need to install a chain gearbox with a gear ratio (gear ratio) of 4. Next, the rotation will be transmitted through the VAZ 2101 driveshaft. The use of a driveshaft will reduce vibration, and the coaxiality of the drive and generator when using the shaft will be uncritical.
- You will need a step-up gearbox (coefficient - 40) and a three-phase generator. The generator rotation speed is about 3000 rpm. The total reduction ratio of the two gearboxes will be 40 x 4 = 160. The generator should be covered with a casing to protect it from moisture and safety. The estimated rotation of the water wheel should be about 20 revolutions per minute.
- An asynchronous motor can be adapted for the generator, and the control unit can be taken from any small machine. You will need a VVG NG cable 2x4 long from the rotor to farm buildings.
conclusions
The total manufacturing costs will be about 10-15 thousand rubles. The main expense item is wage welder and worker helping to make and assemble the structure.
The main advantages of such equipment are the low cost of electricity, environmental Safety, inexhaustibility of the energy source and simplicity of design.
Describe in detail what you may need micro-hydroelectric power station, there is no point - the answers to this question are obvious. Let’s just briefly say that of the well-known alternative energy sources - solar generators, wind and hydroelectric power plants - the latter are potentially the most powerful at a lower cost. In addition, you do not depend on weather factors - wind or sun.
A significant advantage of a homemade micro-hydroelectric power station is also the relative cheapness and availability of materials. Buying a factory hydroelectric power station can cost you $1000-10000,
However, it is mini-hydroelectric power plants that are the most difficult to design and manufacture, especially for an untrained person. For example, it took enthusiast Lukmon Akhmedov (Tajikistan) about 2 years to produce his own version of the power plant. When writing this article, we tried to outline the entire process in sufficient detail and clearly, step by step. We hope that with our help it will take you much less time.
Types of micro hydroelectric power stations
Let us note right away that in this article we will talk about making damless micro-hydroelectric power stations with your own hands. Building a dam is a complex and expensive task, and you will also have to spend a lot of time getting approval from the authorities. With damless hydroelectric power plants, everything is much simpler: they are more environmentally friendly, and their main disadvantage - lower power - is not critical, because we need energy for private, relatively small needs.
Separately, we note that “micro-hydroelectric power station” means a unit with a capacity of up to 100 kW.
So, there are 4 types of damless hydroelectric power stations: “garland” hydroelectric power station, “water wheel”, Darrieus rotor and “propeller”. Also, damless hydroelectric power plants are often called “flowing” or “free flowing”.
- The Garland hydroelectric power station was developed by the Soviet engineer Blinov in the mid-20th century. It consists of small turbines - hydraulic propellers, strung in the form of beads on a cable that is thrown across the river. One end of the cable is attached to the support bearing, and the other rotates the generator shaft. The cable in this unit performs the task of a shaft, whose rotation is transmitted to the generator shaft. The disadvantages of a garland hydroelectric power station include the relative high cost, danger to others (it is likely that such a project will have to be coordinated with the authorities and neighbors) and low power output.
- The water wheel is installed perpendicular to the surface of the water and is less than half immersed in water. It can be activated in two ways: either the flow of water presses on the blades at the bottom of the wheel, causing it to rotate, or the flow of water falls on the wheel from above (see photo below). The efficiency of the latter option is much higher. When manufacturing a turbine of this type, the main issue is the competent choice of the shape of the blades, which will allow the most efficient use of water energy.
- The Darrieus rotor is a vertical rotor with specially designed blades. Thanks to it, the flow of water presses on the blades with different forces, due to which rotation occurs. This effect can be compared to the lift of an airplane wing, which arises due to the difference in pressure above and below the wing.
- The propeller is similar in design to the propeller of a wind generator (hence, in fact, the name) or the propeller of a ship. However, underwater propeller blades are typically much narrower, allowing the flow energy to be used more efficiently. For example, for a river with a current speed of 1-2 m/s, a width of 2 centimeters is sufficient. This design is well suited for fast and deep rivers. Important point: For the safety of swimmers and tourists, be sure to install a barrier and a warning buoy. The unit spins quite quickly and can cause serious injury.
In our opinion, for making do-it-yourself micro-hydroelectric power station It is optimal to use a propeller design or a “water wheel” type design. Note that in factory-produced units, turbines of both types have sufficient complex shape(the so-called “Kaplan turbine”, “Pelton turbine”, etc.), which makes it possible to obtain maximum efficiency for various types flow. However, it is difficult to produce such turbines in “home” production.
A little theory about micro hydroelectric power stations and basic calculations.
The next step is to calculate and measure the flow rate. Determining it by eye is very risky - it’s very easy to make a mistake, so measure 10-20 meters along the shore, throw a float (a chip, a small ball) into the water and measure the time it takes for the chip to float the distance. Divide the distance by time - we get the speed of the current. As practice shows, if it is less than 1 m/s, the construction of a micro-hydroelectric power station in a given stream may be unjustified. If we plan to obtain energy due to height differences, then the power can be approximately calculated using the following formula:
Power N=k*9.81*1000*Q*H,
where k is the efficiency of the system (usually 20%-50%); 9.81 (m/sec2) - acceleration free fall; H – height difference;
Q—water flow (m3/sec); 1000 is the density of water (kg/m3).
As can be seen from the formula, power is directly proportional to speed. If a river has several branches, then it is worth measuring the speed in all of them and choosing the stream that has the highest speed and depth. Please note that measurements must be taken in calm weather.
Find the width and depth of the river in meters. Simplified, we assume that the flow in the cross section has the shape of a rectangle, then multiplying the cross-sectional area by its speed, we obtain the flow rate:
Q = a*b*v. Because in fact, the cross-section of the water flow has a smaller area, then the resulting value should be multiplied by 70% -80%.
If we already have a ready-made generator, then we can estimate the possible working radius of the wheel and required coefficient animations.
Wheel radius (m) = Flow speed (m/s) / Wheel speed (Hz). We can estimate the wheel rotation speed by knowing the operating frequency of the generator (usually in “rpm”) and the expected reduction ratio.
Practice: building micro-hydroelectric power stations ourselves
Now it's time to design and manufacture the turbine. Below we will describe the features of building a micro-hydroelectric power station of the “water wheel” type. This design It is beneficial to use if we have the opportunity to organize a height difference for the flow (or such a difference already exists, for example, it is a drain pipe from a pond). As mentioned above, Special attention should pay attention to the shape of the blades. If you use a wheel with blades in the form of dies (see photo below, in this case the blades are installed at an angle of 45 degrees), then the efficiency of such an installation will be very low.
It is better to use concave blades, which can be obtained, for example, from PVC or metal pipe, cutting it lengthwise into 2 or 4 parts. As practice shows, there should be at least 16 blades. To cut the pipe as straight as possible, draw marking lines along the surface. You can also attach 2 parallel wooden bars and use them as guides. The surface of the blades should be polished, otherwise part of the water energy will be wasted on friction.
You can use an empty cable reel as the wheel itself, or simply make disks of the appropriate diameter. The distance between the disks corresponds to the length of the blades. We connect the disks together and cut out semicircular grooves for installing the blades. Alternatively, the blades can be welded. If the design small size, then you can use a net attached in front of the wheel to protect against debris. In the case when water falls on the blades from above, but the flow is wide enough, it makes sense to make a nozzle (see photo below), thanks to which all the energy of the flow will be used. In the photo above you can see that the waste pipe itself is narrow, so there is no need to use a nozzle. In any case, the flow should fall on the water wheel from above, at about 10 o'clock, if you imagine the wheel in the form of a watch dial.
As supporting structure You can use a welded metal frame. For increasing efficiency Try, if possible, to vary the location of the wheel: closer-further, higher-lower relative to the incoming flow.
Now we need to mount a step-up gearbox (multiplier). Both gear and chain are suitable. Which multiplier to use and what reduction factor is needed depends on the flow power, performance characteristics wheels and generator. Calculating the coefficient is very simple - divide the working number of revolutions of the generator by the number of wheel revolutions per minute. Sometimes you have to use 2 gearboxes different types. To transmit rotation from the wheel to the gearbox or generator, a pipe, driveshaft or other similar element is used.
Any suitable engine is selected as a generator, and it is desirable that it be synchronous. For asynchronous, you will have to add capacitors operating in a star or delta circuit. The characteristics of capacitors depend on the network voltage and motor parameters. The main problem when using asynchronous motor will maintain a constant number of revolutions. If it changes, you will also have to change the capacitors, which can be very troublesome.
