How to make a model hydroelectric power plant with real water. Do-it-yourself hydroelectric generator or homemade hydroelectric power station. Features of connecting a mini hydroelectric power station

If a river or even a small stream flows near your home, then with the help of a home-made mini hydroelectric power station you can get free electricity. It may not be a very big budget replenishment, but the realization that you have your own electricity costs much more. Well, if, for example, in a country house, there is no central power supply, then even small power capacities will be simply necessary. And so, to create a home-made hydroelectric power station, at least two conditions are necessary - the presence of a water resource and desire.

If both are present, then the first thing to do is to measure the flow rate of the river. It is very simple to do this - throw a twig into the river and measure the time during which it swims 10 meters. By dividing meters by seconds, you get the speed of the current in m/s. If the speed is less than 1 m / s, then a productive mini hydroelectric power station will not work. In this case, you can try to increase the flow rate by artificially narrowing the channel or by making a small dam if you are dealing with a small stream.

As a guide, you can use the ratio between the flow velocity in m/s and the power of the electricity removed from the propeller shaft in kW (propeller diameter 1 meter). These are experimental data, in reality the received power depends on many factors, but it is suitable for evaluation. So:

0.5 m/s - 0.03 kW,
0.7 m/s - 0.07 kW,
1 m/s - 0.14 kW,
1.5 m/s - 0.31 kW,
2 m/s - 0.55 kW,
2.5 m/s - 0.86 kW,
3 m/s -1.24 kW,
4 m/s - 2.2 kW, etc.

Power homemade mini hydroelectric power station proportional to the cube of the flow rate. As already mentioned, if the flow rate is insufficient, try to artificially increase it, if this is of course possible.

Types of mini hydroelectric power plants

There are several basic options for homemade mini hydroelectric power plants.

Water wheel

This is a wheel with blades mounted perpendicular to the surface of the water. The wheel is less than half immersed in the stream. Water presses on the blades and rotates the wheel. There are also turbine wheels with special blades optimized for the liquid jet. But these are rather complex designs, rather factory-made than home-made.

Rotor Daria

It is a vertical axis rotor used to generate electrical energy. A vertical rotor that rotates due to the pressure difference on its blades. The pressure difference is created due to the fluid flow around complex surfaces. The effect is similar to the lift of a hydrofoil or the lift of an airplane wing. This design was patented by Georges Jean-Marie Darier, a French aeronautical engineer, in 1931. It is also often used in the construction of wind turbines.

Garland hydroelectric power station

The hydroelectric power plant consists of light turbines - hydro vingrotors, strung and rigidly fixed in the form of a garland on a cable thrown across the river. One end of the cable is fixed in the support bearing, the other end rotates the generator rotor. The cable in this case plays the role of a kind of shaft, the rotational movement of which is transmitted to the generator. The flow of water rotates the rotors, the rotors rotate the cable.

Propeller

Also borrowed from the designs of wind farms, such a "underwater windmill" with a vertical rotor. Unlike an air propeller, an underwater propeller has blades of a minimum width. For water, a blade width of only 2 cm is sufficient. With this width, there will be a minimum resistance and a maximum rotation speed. This width of the blades was chosen for a flow velocity of 0.8-2 meters per second. At high speeds, other sizes may be optimal. The propeller does not move due to water pressure, but due to the occurrence of lift. Just like an airplane wing. The propeller blades move across the flow rather than being carried along by the flow in the direction of the flow.

Advantages and disadvantages of various homemade mini hydroelectric systems

Flaws garland hydroelectric power station obvious: high material consumption, danger to others (long underwater cable, rotors hidden in the water, blocking the river), low efficiency. Garland HPP is a kind of small dam. It is advisable to use in deserted, remote places with appropriate warning signs. You may need permission from the authorities and environmentalists. The second option is a small stream in your garden.
Rotor Daria- difficult to calculate and manufacture. At the beginning of work, it needs to be untwisted. But it is attractive in that the rotor axis is located vertically and the power take-off can be made above the water, without additional gears. Such a rotor will rotate with any change in the direction of flow - this is a plus.

Most widespread at construction of self-made hydroelectric power plants got propeller and water wheel diagrams. Since these options are relatively easy to manufacture, require minimal calculations and are implemented at minimal cost, have high efficiency, are easy to set up and operate.

If you do not have a water energy resource, you can independently make a home wind farm.

P An example of the simplest mini hydroelectric power station

The simplest hydroelectric power station can be quickly built from an ordinary bicycle with a dynamometer for a bicycle headlight. Several blades (2-3) must be prepared from galvanized iron or not thick sheet aluminum. The blades should be 2-4 cm long from the wheel rim to the hub, and 2-4 cm wide. These blades are installed between the spokes in any improvised way or pre-prepared mounts.
If you are using two blades, then set them opposite each other. If you want to add more blades, then divide the circumference of the wheel by the number of blades and install them at regular intervals. You can experiment with the depth of immersion of a wheel with blades in water. Usually it is immersed from one third to half.
The option of a camping wind farm was considered earlier.

Such a micro hydroelectric power station does not take up much space and will serve cyclists well - the main thing is the presence of a stream or river - which is usually the case at the campsite. A mini hydropower plant from a bicycle will be able to light a tent and charge cell phones or other gadgets.

I have always been attracted to getting free energy from natural resources. And somehow I had the idea to make a simple mini power plant that would generate electricity from a passing water stream.

It all started with the idea of using the drum of an old washing machine as a water wheel, a miniature homemade hydroelectric power plant.

Straight blades made of moisture-resistant plywood were attached to the drum using metal corners.

Torque from the water wheel is transmitted by a belt to a bicycle dynamo (DC generator). The generated electricity is fed to the LED. It is enough to turn the wheel slightly with your hand, and the LED will start flashing.

The basis of the whole structure is a bicycle frame.

Two bearings allow the water wheel to spin freely.

The first tests on a small river showed that the water wheel on the frame is set too high, which prevents the flow of water from spinning it normally.
After small changes in the frame design, the wheel began to be located lower and the rotation speed increased dramatically. As a result, the dynamo began to rotate and the 4.5 V LED lit up.

This is how a home-made hydroelectric power station turned out from the old trash.
Further, the mini hydroelectric power station assembly was installed on a small stream.

It produces only a few volts, but they are enough to light the LED.

It was a good experiment to start with.

Further improvement in the project

Further improvement of the water wheel should affect:

Build a mini-dam to increase water pressure. At the same time, it is not planned to completely block the river so that the fish can leave in the second stream.
Under the dam, install a pipe through which water will flow to a makeshift turbine. Arrange a casing from a rubber conveyor belt in the pipe. By blocking the flow of water through the pipe, you can service the mechanisms.
According to calculations, the turbine will produce about twice as much power as the water wheel. In addition, replacing the water wheel with a turbine should eliminate the problem of freezing in winter.
The flow of water will spin the turbine, transferring torque to the generator. The turbine will be held on two bearings made of solid wood. With regular lubrication, they will last a long time. The thrust washer will keep the mechanism from lateral displacement.
Make metal blades, calculating the angle at which they need to be bent (the power of the hydroelectric power plant depends on this parameter). The blades will need to be screwed using rubber gaskets to avoid their separation.
To transmit torque, use a shaft assembled from pipes.
Install generator. Install a pulley smaller than the one mounted on the shaft on the generator. This will increase the speed, which is necessary for the efficient operation of the generator.

The generator should produce about 600 watts of electricity. This will make it possible to connect household appliances. If the next stage of the experiment is successful, it will be possible to think about further modernization in order to generate several kilowatts of electricity.

Micro-HPP is a power plant with low power (up to 100.0 kW), which is used to produce electrical energy by converting the kinetic energy of water.

Operating principle

The principle of operation of micro-hydroelectric power stations is similar to the operation of large and small hydroelectric power stations. The difference lies only in the capacity of the installed equipment and the amount of electricity generated.
The production of electric current is carried out by a generator, the rotational movement of the rotor of which is transmitted from a hydraulic turbine.
In order for the turbine to come into rotational motion, a water pressure is created in the reservoir where a mini hydroelectric power station is installed. This can be a pressure created by the natural flow of water masses, or created by the construction of a dam or other technical structure. In certain cases, both methods of generating pressure can be used at the same time.
Under the action of pressure, water flows rush in the required direction, a turbine is mounted in the alignment of their movement, on the blades of which the energy of moving water masses enters. This kinetic energy of water is converted by the turbine into rotational motion, which is transmitted to the generator shaft by means of a mechanical transmission (reducer).

The source of energy can be:

rivers of various sizes and intensities of flow and streams,
height differences on the spillways of reservoirs for various purposes;
technological watercourses;
height differences on pipelines for various purposes.

Depending on the type of equipment used and how it is installed, the principle of operation of a hydroelectric power plant may vary. These may be the following options:

The principle of "water wheel" - with this option, the receiving wheel is partially immersed in water parallel to its surface. Water flows, moving along a natural channel, put pressure on the blades placed on the wheel and cause it to rotate. The wheel, in turn, through a gearbox and other mechanical devices, creates a rotational movement of the generator.
Construction in the form of a garland - a cable is mounted from opposite banks, on which special rotors are installed. Water, moving, rotates the rotors, the rotational movement of which is transmitted to the cable. The cable, rotating, transmits rotational motion to the generator installed on the shore.
With the use of the Darrieus rotor - the principle of operation of the turbine is based on the use of the pressure difference on the rotor blades.
Using the propeller principle, the blades of the device are placed in water and, under the influence of water, come into rotation, which is transmitted to the shaft of a generator that generates electric current.

Benefits of using micro-hydro power plants:

There is no need to change the natural landscape of the area;
The quality of water is not affected by third parties, it retains its properties;
Not dependent on the impact of natural phenomena;
Possibility of use in a year-round cycle of work;
There is no need to build expensive hydraulic structures.

Types

Depending on the method of using water energy, micro-hydroelectric power plants are divided into:

Dam.
The method of creating water pressure is based on the construction of a dam, from which water flows through a special chute (pipe) to the turbine.
Derivative.
When constructing a micro-hydroelectric power station of this type, natural water pressure is used (fast, mountain rivers). In this case, part of the water is diverted from the riverbed and directed to the turbine, after which the water is discharged into the mainstream.
Dam-derivation.
In this type of power plant, both the natural head and the pressure created by the dam are used.
Free flow.
This type of micro-hydroelectric power station does not involve the construction of pressure structures, the kinetic energy of water is used in its free flow, by installing special devices, floating or submersible.

Manufacturers and prices

Nowadays, more and more people are interested in alternative energy sources, and, accordingly, the demand for equipment used for energy production is increasing. In this regard, companies in many countries of the world, including Russia, are engaged in the production of such equipment.

Equipment for micro-hydroelectric power plants, both for individual units and in sets, in our country are engaged in:

AEnergy LLC, Moscow.
The company manufactures equipment for various areas of electrical energy production using alternative sources (wind generators, solar power plants, etc.). In the line of manufactured goods, power equipment for micro and mini hydroelectric power plants.
Intersectoral scientific and technical association "MNTO INSET", St. Petersburg.
The company performs the whole range of works from design to turnkey delivery of finished
construction object. In the product line of micro-hydro power plants with various
impeller types and power from 5.0 to 180.0 kW, as well as various
hydraulic units.

The cost of a set of equipment, depending on the type of power plant and its capacity, is from 350,000.00 rubles.

Among foreign manufacturers, the most famous products of such companies as:

CINK Hydro-Energy Czech Republic.
The company manufactures hydroelectric power plants with horizontal and vertical turbines, from 5.0 to 3000 kW, as well as microturbines.
The cost of sets is from 500,000.00 rubles.
"Micro hydro power" China.
The company manufactures hydroelectric power plant kits with power from 1.0 to 3000 kW. The cost is from 300,000.00 to 4,000,000.00 rubles.
Engineering and technical company OsOO Hydroponics, Bishkek, Kyrgyzstan.
The company produces hydroelectric power plants with a capacity of 0.5 to 5.0 kW. The cost is from 60,000.00 to 300,000.00 rubles.

How to DIY

In order to make the simplest device for generating electrical energy, you must have the skills to work with a hand tool, free time, desire and a pond.

As a source of electrical energy, you can use a car generator, for the rotation of the rotor of which, it is necessary to make the following design.

In accordance with the available reservoir, it is necessary to decide which wheel option will be used - vertical or horizontal. This affects the spatial design of the assembled installation.
As a wheel, any available is used. Good for a bicycle wheel.
Blades are attached to the wheel rim, which are made of metal, hard plastic or other material available.
A gear or pulley is attached to the wheel shaft. Depending on the fixed element, chain or belt transmission will be performed in the future.
The wheel is mounted on the structure and placed in the water, so that when the wheel is placed horizontally, 1/3 is above the water surface, when placed vertically, water enters the blades, and the wheel axle is out of the water.
Depending on the water body, a generator is installed. This can be done directly on the assembled metal structure, or installed on the shore.
A gear or pulley is installed on the generator shaft, which must be of a smaller diameter than those installed on the wheel.
Pulleys or gears mounted on the wheel and generator shaft are connected.

The installation is ready to go.

This option for obtaining electrical energy can be used by tourists and travelers to recharge mobile phones, tablets and other non-energy-intensive equipment.

Micro-hydroelectric power station on the stream

When living in a rural area or having a summer cottage near which a stream flows, it is possible to resolve the issue of power supply to these facilities by installing a micro-hydroelectric power station on such a water body.
To power such an object, a car generator will no longer be enough, because the installed power, even a country house, is much more than such a device can produce.
The most correct solution is to purchase a set of micro-hydroelectric power stations with a capacity of up to 10.0 kW, and perform the installation yourself. This will reduce costs, and the installation process itself can be performed even by a person with minimal knowledge in mechanics and electrical engineering.

A set of such equipment, as a rule, includes the following elements:

Hydro turbine.
Multiplier to increase the generator shaft speed in relation to the turbine speed.
A device that provides self-acceleration of the turbine.
Piping kit.
Generator.
Control and automation system.

Depending on the flow of water that the stream provides, the type of turbine is selected, this is usually a propeller or diagonal design.
In accordance with the manufacturer's instructions, equipment is installed and consumers are connected.

Micro - whirlpool hydroelectric power station

Installations operating on the principle of a whirlpool, it is advisable to install on small rivers and full-flowing streams. The power of this type of micro hydroelectric power station is up to 100.0 kW.
During the construction of such stations, a special chute is mounted into which water masses from a river or stream enter. At the bottom of the gutter, a cylindrical structure is made at the bottom of which a hole is made. Water enters through the chute into the receiver-cylinder, moving tangentially to the walls of the latter, as a result of which, inside the cylinder, it spins in a whirlpool, its speed increases, and it flows out through the lower hole, falling on the turbine blades.

Due to the constant rotation of water, hydroelectric power plants of this type operate in a year-round cycle. The disadvantage of whirlpool micro hydroelectric power plants is the high cost due to the large volume of concrete work.

Pros and cons

The use of micro-hydroelectric power stations makes it possible to obtain a positive effect from their use in the economic and social spheres and the environmental safety of the territories where such structures are being built.
The production of electrical energy allows you to ensure the energy independence and security of the territory, an individual enterprise or a property. During construction, the construction of large hydraulic structures is not required, and as a result, the cost of construction and installation works is reduced.
An important advantage of small hydropower is the environmental safety of such installations. There are no harmful effects on flora and fauna, and the quality of the water remains unchanged.

Summing up the advantages of using micro hydroelectric power plants, their positive properties include the following:

Environmental friendliness and safety of installations;
Water energy is a renewable and inexhaustible source of energy;
The ability of installations to work offline;
The generated electrical energy has a low cost;
Long terms of operation;
Technical reliability of installations.

Any technical object, along with positive properties, always has negative ones. For complex technical structures, which are micro hydroelectric power plants, there may be emergency situations, as a result of which, the production of electrical energy may be stopped, and therefore, consumers will be de-energized.
The seasonality of the operation of stations is also a disadvantage of such installations. This determines the regions of use or the need for special devices and structures.

Combining the disadvantages of using micro hydroelectric power plants, their negative properties can be related to:

High cost of equipment and construction and installation works;
Withdrawal from common use of significant areas (flooding, during the construction of dams and reservoirs);
Limited use due to the possibility of installation of installations and the climate of the region where the equipment is installed;
The presence of a potential hazard to living organisms living in water bodies.

The use of small hydroelectric power plants is one of the directions for the development of renewable energy sources and already today competes with traditional sources of electricity, being an effective direction for the development of alternative energy.

The “greens” of the whole world are increasingly and more actively protesting against the development of new deposits of oil, gas, coal, as well as the massive use of internal combustion engines throughout the world, which bring the most severe pollution to our environment. Celebrities from the world of fashion, theater, cinema, urge to live more economically in terms of energy consumption. They install solar panels, wind generators on the roofs of their mansions (like actor Leonardo DiCaprio, for example).

More and more ordinary people also understand that something may depend on their behavior, and if at least one person finds an alternative to the internal combustion engine, then the world will become a little cleaner. Therefore, in villages, towns and in our country, where there is falling or running water, a certain pool of water on a hill, there is an opportunity to make a mini hydroelectric power station with your own hands and, thereby, help yourself and Her Majesty Nature. After all, this is an alternative to a gasoline or diesel generator, which still runs on fuel and produces caustic exhaust into the environment.

And what if more than one person, more than one household decided to find an alternative way to get electricity? If a whole village, village, aul? Here, the load on Nature will decrease significantly. And the consumer will have more money in his pocket for household needs, because electricity from a mini hydroelectric power station created by the hands and mind of enthusiasts comes out about three times cheaper than buying it from regular producers (thermal power plants, nuclear power plants, industrial hydroelectric power plants).

Looking for the right water

Recently, I saw a short video showing how in an ordinary Indian village, students from one of the Western colleges decided to make a mini hydroelectric power station. There is no electricity in that wilderness, young people are fleeing to the cities, but what will happen if you give the inhabitants light? There is no river as such in the village, but there is a reservoir. A natural bowl with a huge amount of water is located slightly above the level of the village. What did the students come up with?

They realized with their smart heads that since there is no flow from Nature here, it can be created! By the hands of hired workers, a covered long pipe with a diameter of a meter was mounted, and one end of it was closed to a reservoir, and the other - below, went into a small and slow-moving river. Due to the height difference, the water from the reservoir rushed down the pipe, accelerating more and more, and at the exit a rather powerful stream was already created, which rested against the blades of the mini hydroelectric power station. The pipe, in which the water of the reservoir was enclosed, runs down the hillside so picturesquely that it seems as if a huge python slowly crawls from top to bottom and, with its size, inspires horror in the locals. I want to touch it with my hands, feel it, feel its power.

If something similar is being created in an Indian village, then why not try to do the same in a Russian one? If there is no fast-flowing river nearby, but there is a reservoir, then the construction of a mini hydroelectric power station is also possible. You just need to look at the terrain, but one thing is clear: the reservoir - let it be natural or artificial - should be located higher than the place where the hydroelectric power station will be installed. If the height difference is significant - even better! The flow of water will run stronger from top to bottom, which means that the possible power of the received electricity will increase.

It is not necessary to buy expensive pipes to organize artificial water flow. You can make a kind of gutter with your own hands, and let the water from the reservoir accelerate along it. To begin with, it is better to take any means at hand, old pipes, albeit of a small diameter for the time being, and build a trial version of draining water from a reservoir, which is located above. So it will be possible to measure the flow rate (I already wrote how to do this earlier). If a fast-moving river flows nearby, then there is no need to build either dams or gutters, or artificially create a flow of water. Mini HPPs in the form of a string, a propeller, a Dardieu rotor or a water wheel can be installed in such places without any problems.

It will be important to protect the building. How? In front of the mini hydroelectric power station, a protective screen made of mesh, or a diffuser, should be installed so that the fragments of trees floating along the river, or even whole logs, as well as live and dead fish, all kinds of garbage, do not fall on the turbine blades, but float past.

The simplest mini hydroelectric station do-it-yourself

Almost everyone is able to create their own mini-hydroelectric power station with their own hands. Examples? Many tourists use an ordinary bicycle to get lighting in the conditions of a hike, on which they move. On any bicycle wheel, they install jumpers made of pieces of, say, thin iron between the spokes and first with their hands, and then with pliers, lead the edges of the sheet behind the spoke, thereby fixing the jumper. The length of the jumper should correspond to half the diameter of the wheel, that is, cover the distance from the rim to the hub. In fact, it should be equal to the length of the spoke. It would be optimal to install four such jumpers according to the type of cardinal points: North, South, West, East. Next, you need a regular bike generator and a flashlight connected to it.

It's time to go hiking. For the night you need to stop by the river. Well, let the mosquitoes bite! But it will turn out to make a video of the party, make photos by the fire. It's very picturesque! The water in the river must have a noticeable flow, and then our camping mini hydroelectric power station will work. "Let there be light!" - said the fitter and made a circuit. No, this is not about us.

"Let there be light!" - said the tourist and lowered the wheel with iron bridges a third into the water of the running river. The bicycle itself is placed on a small stand, or suspended from a tree or a peg on the shore so that the wheel is a third immersed in the stream. Water presses on the jumpers, turns the wheel, the generator converts the energy of the water into current and the mini-flashlight illuminates the parking lot.

There is no risk that the batteries are defective, as in the case of using a conventional flashlight, there is no risk that they will "sit down", they do not need to be taken on a hike in large quantities. The flow of the river will not disappear. Tourists, most often, prefer to stay in proven places. So, once having received an electric current through a mini-hydroelectric power station at the place of lodging for the night, they will remember this place and try to while away the dark time of the day here.

Difficulties in matching

However, lighting one candle, figuratively speaking, is one thing, but lighting thousands, giving people light, as Prometheus did, is a completely different matter. A compact hydroelectric power plant as a source of electricity, by its appearance in everyday use, can disrupt the established picture and state of affairs.

The largest monopolies are accustomed to the fact that it is they who produce electricity for small settlements, marketing subsidiaries are accustomed to receiving money for the delivery of goods - kWh to the consumer. Where to enter a mini-hydroelectric power station in this scheme? And still not controlled by monopolists? I must say right away that it will not be easy to agree on such a project with the local authorities in Russia, as well as any other new business. But the result is worth the effort.

In general, a compact (mini) hydroelectric power station means such a station that produces power up to 100 kW. Craftsmen, working with their hands and head, can quite easily build this useful thing in their village or village, even in private households. But only if there are appropriate natural conditions and a desire to create something NEW, save money, that is, pay less for electricity in the future.

If you watch a video, or a photo of some mini hydroelectric power plants, you will see that sometimes they look very strange. But after all, for contemporaries of Leonardo da Vinci, his flywheels with huge wings also seemed at least strange, and with his daring experiments and ideas, the great Italian completely terrified many people of his time. So what? We don't remember those people. And the drawings and creations of Leonardo will live for centuries. Build a mini-hydroelectric power station with your own hands, experiment, go for it! Nature and descendants will only say “Thank you” to you!

Mikhail Bersenev

In Tajikistan, there are also craftsmen, no worse than Indian ones:

Next in line are structures, the prototype of which was the free-flow (1964 model) daisy-chain hydroelectric power station of V. Blinov.

The hydroelectric power plants that will be discussed are free-flow, with a rather original turbine from the so-called Savonius rotors strung on a common (maybe flexible, composite) working shaft. They do not require dams and other large-scale hydraulic structures for their installation. Able to work with full efficiency even in shallow water, which, combined with the simplicity, compactness and reliability of the design, make these hydroelectric power plants very promising for those farmers and gardeners whose plots of land are located near small watercourses (rivers, streams and ditches).

Unlike dams, free-flow hydropower plants, as is known, use only the kinetic energy of flowing water. To determine the power, there is a formula here:

N=0.5pV3Fn (1),

N - power on the working shaft (W),
- р - water density (1000 kt/m3),
- V - river flow velocity (m/s),
- F - cross-sectional area of the active (immersed) part of the working body of the hydraulic machine (m2),
- n - energy conversion efficiency.

As can be seen from formula 1, at a river speed of 1 m/s, ideally (when n = 1) a power equal to only 500 W per square meter of the active part of the hydraulic machine falls. This value is clearly small for industrial use, but it is quite sufficient for the subsidiary farm of a farmer or summer resident. Moreover, it can be increased by the parallel operation of several "hydraulic garlands".

And one more subtlety. The speed of the river in its different parts is different. Therefore, before starting the construction of a mini-hydroelectric power station, it is necessary to determine the energy potential of your river using a simple method outlined. We only recall that the distance traveled by the measuring float and divided by the time of its passage will correspond to the average flow velocity in this section. It should also be noted that this parameter will change depending on the season.

Therefore, the calculation of the design should be made, guided by the average (for the planned period of operation of the mini-HPP) speed of the river.

Fig.1. Savonius rotors for homemade daisy-chain mini hydroelectric power stations:

a, b - blades; 1 - transverse, 2 - end.

Next, you need to determine the size of the active part of the hydraulic machine and its type. Since the entire mini hydroelectric power station should be as simple and easy to manufacture as possible, the most suitable type of converter is the Savonius rotor of the end design. When working with complete immersion in water, the value of F can be taken equal to the product of the rotor diameter D and its length L, and n=0.5. The rotation frequency f with an accuracy acceptable for practice is determined by the formula:

f=48V/3.14D (rpm) (2).

To make the hydropower plant as compact as possible, the power specified in the calculation should be correlated with the actual load, the power supply of which should be provided by the minihydroelectric power station (since, unlike a wind turbine, current will be continuously supplied to the consumer's network here). As a rule, this electricity is used for lighting, powering the TV, radio, refrigerator. And only the latter is included in the work during the day constantly. The rest of the electrical appliances work mainly in the evening. Based on this, it is advisable to focus on the maximum power from one "hydraulic garland" of the order of 250-300 W, covering the peak load with a battery charged from a mini-hydroelectric power station.

The transmission of torque from the working shaft of the hydraulic power plant to the pulley of the electric generator is usually carried out using an intermediate transmission. However, this element, strictly speaking, can be excluded if the generator used in the design of the microhydroelectric power station has an operating rotation speed of less than 750 rpm. However, direct communication often has to be abandoned. After all, for the vast majority of generators of domestic production, the operating speed of rotation at the beginning of the "delivery" of power lies in the range of 1500-3000 rpm. This means that additional coordination of the shafts of the hydraulic power plant and the electric generator is needed.

Well, now that the preliminary theoretical part is over, let's consider specific designs. Each of them has its own merits.

Here, for example, is a semi-stationary free-flow mini-hydroelectric power station with a horizontal arrangement of two coaxial, rotated 90 ° relative to each other (to facilitate self-starting) and rigidly connected transverse-type Savonius rotors. Moreover, the main parts and components of this home-made hydropower plant are made of wood as the most accessible and “obedient” building material.

The proposed mini hydroelectric power station is submersible. That is, its support frame is located across the watercourse at the bottom and is reinforced with stretch cables or poles (if, for example, there are walkways, a boat pier, etc. nearby). This is done in order to avoid the entrainment of the structure by the watercourse itself.

Fig.2. Submersible mini hydroelectric power station with a horizontal arrangement of rotors of a transverse type:
1 - spar-base (beam 150x100, 2 pcs.), 2 - lower cross-beam (board 150x45, 2 pcs.), 3 - middle cross-beam (beam 150x120, 2 pcs.), 4 - riser (round timber with a diameter of 100, 4 pcs. .), 5 upper spar (board 150x45, 2 pcs.), 6 - upper cross member (board 100x40, 4 pcs.), 7 - intermediate shaft (stainless steel, rod with a diameter of 30), 8 - pulley block, 9 - DC generator current, 10 - "gander" with a porcelain roller and a two-core insulated wire, 11 - base plate (board 200x40), 12 - drive pulley, 13 - wooden bearing assembly (2 pcs.), 14 - rotor "hydraulic garland" (D600, L1000, 2 pcs.), 15 disk (from boards 20-40 mm thick knocked down into a shield, 3 pcs.); metal fasteners (including extensions, hubs of the outer discs) are not conventionally shown.

Of course, the depth of the river at the installation site of a mini hydroelectric power station should be less than the height of the support frame. Otherwise, it is very difficult (if not impossible) to avoid water entering the electric generator. Well, if the place where it is supposed to place a mini hydroelectric power station has a depth of more than 1.5 m, or there is a high flow and flow rate that varies greatly throughout the year (which, by the way, is quite typical for snow-fed watercourses), then this design is recommended to be equipped with floats. This will also make it easy to move it when installed on the river.

The support frame of a mini hydroelectric power station is a rectangular frame made of timber, boards and small logs fastened with nails and wire (cables). The metal parts of the structure (nails, bolts, clamps, corners, etc.) should be, if possible, made of stainless steel or other corrosion-resistant alloys.

Well, since the operation of such a mini hydroelectric power station is often possible in Russia only seasonally (due to the freezing of most rivers), then after the expiration of the operation, the entire structure pulled ashore is subject to a thorough inspection. Timely change rotten wooden elements, rusted, despite the precautions taken, metal parts.

One of the main components of our mini hydroelectric power station is a "hydropower garland" of two rigidly fixed (and constituting a single unit on the working shaft) rotors. Their discs are easy to make from boards 20-30 mm thick. To do this, having made a shield out of them, using a compass, build a circle with a diameter of 600 mm. After that, each of the boards is cut according to the curve obtained on it. Having knocked the blanks together on two slats (to give the required rigidity), they repeat everything three times - according to the number of required disks.

As for the blades, it is advisable to make them from roofing iron. And better - from cylindrical stainless containers (barrels) of suitable size and cut in half (along the axis), in which agricultural fertilizers and other aggressive materials are usually stored and transported. In extreme cases, the blades can also be made of wood. But their weight (especially after a long stay in the water) will greatly increase. And this should be remembered when creating a mini hydroelectric power station on floats.

Spike supports are attached to the ends of the "hydroenergy garland". In fact, these are short cylinders with a wide flange and an end slot for a key. The flange is attached to the respective rotor disc with four bolts.

To reduce friction, bearings are provided located on the middle crossbars. And since ordinary ball or roller bearings are unsuitable for working in water, they use ... home-made wooden ones. The design of each of them consists of two clamps and insert plates with a hole for the passage of the spike support. Moreover, the middle bearing shells are positioned so that the wood fibers here run parallel to the shaft. In addition, special measures are taken to ensure that the insert plates are firmly fixed against lateral displacements. Do this with the help of tightening bolts.

Fig.3. Plain bearing assembly:
1 - crimping bracket (St3, strip 50x8, 4 pcs.), 2 - middle frame cross member, 3 - crimping insert (made of hard wood, 2 pcs.), 4 replaceable insert (made of hard wood, 2 pcs.) , 5 - M10 bolt with Grover's nut and washer (4 sets), 6 - M8 stud with two nuts and washers (2 pcs.).

As an electric generator in the considered microhydroelectric power station, any of the automobile ones is used. They give out 12-14 V DC and easily dock with both the battery and electrical appliances. The power of these machines is about 300 watts.

Quite acceptable for self-production is the design of a portable mini hydroelectric power station with a vertical arrangement of a "garland" and a generator. Such a hydroelectric station, according to the author of the development, is the least material-intensive. The supporting structure of the installation, which fixes its position in the river bed, is a hollow steel rod (for example, from pipe sections). Its length is chosen based on the nature of the bottom of the watercourse and the speed of the current. Moreover, such that the sharp end of the rod, driven into the bottom, would guarantee the stability of the mini-hydroelectric power station and its inseparability by its course. It is also possible to use additional stretch marks.
Having determined the active surface of the rotor by formula (1) and measuring the depth of the river at the installation site of the mini hydroelectric power station, it is easy to calculate the diameter of the Savonius rotors used here. To make the design simple and self-starting, it is advisable to make a "hydraulic garland" of two rotors connected so that the blades of the first are shifted by 90 ° relative to the second (along the axis of rotation). Moreover, to increase the efficiency of work, the structure on the side of the oncoming flow is equipped with a shield that plays the role of a guide vane. Well, the working shaft is mounted in plain bearings of the upper and lower supports. In principle, with a short operating time of a mini hydroelectric power station (for example, on a camping trip), large-diameter ball bearings can also be used. However, if there is sand or silt in the water, after each use, these units will have to be washed in clean water.

Rice. 4. Mini hydroelectric power station with a vertical arrangement of end-type rotors:
1 - support rod, 2 - lower bearing assembly, 3 - hydropower garland disk (3 pcs.), 4 - rotor (D600, 2 pcs.), 5 - upper bearing assembly, 6 - working shaft, 7 - transmission, 8 - electric generator, 9 - "gander" with a porcelain roller and a two-core insulated wire, 10 - a generator mounting clamp, 11 - a movable shield-guide; a, b - blades: extensions at the upper end of the support rod are conventionally not shown.

The fastening of the supports to the rod is bolted and welded, depending on the weight of the “hydraulic garland” and the need to disassemble it into parts. The upper end of the working shaft of the hydraulic machine is also the input shaft of the multiplier, which (as the most simple and technological) can be used as a belt.

The electric generator is taken again by a car. It is easy to attach it to the support rod with a clamp. And the wires themselves coming from the generator must have reliable waterproofing. In the illustrations, the exact geometric proportions of the intermediate transmission are not conventionally shown, since they depend on the parameters of the particular generator you have. Well, transmission belts can be made from an old car camera by cutting it into tapes 20 mm wide, followed by twisting into bundles.

For the power supply of small villages, a daisy minihydroelectric power station designed by V. Blinov is suitable, which is nothing more than a chain of barrel-shaped Savonius rotors with a diameter of 300-400 mm, fixed on a flexible cable stretched across the river. One end of the cable is attached to a hinged support, and the other through a simple multiplier to the generator shaft. At a flow rate of 1.5-2.0 m/s, the chain of rotors makes up to 90 rpm. And the small size of the elements of the “hydropower garland” makes it possible to operate this microhydroelectric power station on rivers with a depth of less than one meter.

It must be said that before 1964 V. Blinov managed to create several portable and stationary mini hydroelectric power plants of his own design, the largest of which was a hydroelectric power station built near the village of Porozhki (Tver region). A pair of garlands here drove two standard autotractor generators with a total power of 3.5 kW.

MK 10 1997 I. Dokunin