Regular increase in electricity prices makes many think about the issue of alternative sources of electricity. One of the best solutions in this case is a hydroelectric power plant. The search for a solution to this issue concerns not only the scale of the country. Increasingly, you can see mini-hydroelectric power plants for the home (cottage). The costs in this case will be only for construction and maintenance. The disadvantage of such a structure is that its construction is possible only under certain conditions. Water flow is required. In addition, the construction of this structure in your yard requires permission from local authorities.
Scheme of mini-hydro power plant
The principle of operation of a hydroelectric power station for a home is quite simple. The structure diagram is as follows. Water falls on the turbine, causing the blades to rotate. They, in turn, due to the torque or pressure drop, drive the hydraulic actuator. From it, the received power is transmitted to the electric generator, which generateselectricity.
At present, the hydroelectric scheme is most often completed with a control system. This allows the design to work in automatic mode. In case of need (for example, an accident), it is possible to switch to manual control.
Varieties of mini-hydro power plants
It should be understood that mini-hydroelectric power plants can produce no more than three thousand kilowatts. This is the maximum power of such a structure. The exact value will depend on the type of HPP and the design of the equipment used.
Depending on the type of water flow, the following types of stations are distinguished:
- Channel, characteristic of the plains. They are installed on rivers with low flow.
- Stationary use the energy of water rivers with a fast flow of water.
- HPPs installed in places where the water flow drops. They are most often found in industrial organizations.
- Mobile, which are built using a reinforced sleeve.
For the construction of a hydroelectric power station, even a small stream flowing through the site is enough. Owners of houses with central water should not despair.
One of the American companies has developed a station that can be built into the water supply system at home. A small turbine is built into the water supply system, which is set in motion by the flow of water moving by gravity. It slows down the speedwater flow, but reduces the cost of electricity. In addition, this installation is completely safe.
Even mini-hydroelectric power plants are being built in the sewer pipe. But their construction requires the creation of certain conditions. Water through the pipe should flow naturally due to the slope. The second requirement is that the pipe diameter must be suitable for the equipment. And this cannot be done in a detached house.
Classification of mini HPPs
Mini hydroelectric power plants (the houses that use them are mostly private sector) are most often one of the following types, which differ in how they work:
- The water wheel is the traditional type and the easiest to make.
- Propeller. Used in cases where the river has a channel with a width of more than ten meters.
- The garland is installed on rivers with a slight flow. Additional structures are used to increase the speed of water flow.
- The Darrieus rotor is usually installed in industrial plants.
These options are common because they do not require the construction of a dam.
Waterwheel
This is a classic type of hydroelectric power plant, which is most popular for the private sector. Mini hydroelectric power plants of this type are a large wheel that can rotate. Its blades are lowered into the water. The rest of the structure is above the channel, forcing the whole mechanism to move. Poweris transmitted through a hydraulic drive to a generator that generates current.
Propeller station
On the frame in a vertical position is a rotor and an underwater windmill, lowered under water. The windmill has blades that rotate under the influence of the flow of water. The best resistance is provided by blades two centimeters wide (with a fast flow, the speed of which, however, does not exceed two meters per second).
In this case, the blades are set in motion due to the resulting lifting force, and not due to water pressure. Moreover, the direction of movement of the blades is perpendicular to the direction of flow. This process is similar to wind farms, only it works underwater.
Garland HPP
This type of mini-hydroelectric power station is a cable stretched over the bed and fixed in a thrust bearing. On it, in the form of a garland, turbines of small size and weight (hydraulic rotors) are hung and rigidly fixed. They consist of two semi-cylinders. Due to the alignment of the axes, when lowered into the water, a torque is created in them. This leads to the fact that the cable bends, stretches and begins to rotate. In this situation, the cable can be compared to a shaft that serves to transmit power. One end of the rope is connected to the gearbox. Power is transferred to it from the rotation of the cable and hydraulic rotors.
The presence of several "garlands" will help to increase the power of the station. They can be connected to each other. Even that doesn't improve much.efficiency of this HPP. This is one of the disadvantages of such a structure.
Another disadvantage of this species is the danger it creates for others. This kind of station can only be used in deserted places. Warning signs are mandatory.
Rotor Daria
A mini-hydroelectric power plant for a private house of this type is named after its developer - Georges Darier. This design was patented in 1931. It is a rotor with blades on it. For each of the blades, the necessary parameters are selected individually. The rotor is lowered under water in a vertical position. The blades rotate due to the pressure drop that occurs under the action of water flowing over their surface. This process is similar to the lift force that makes planes take off.
This type of HPP has a good efficiency index. The second advantage is that the direction of the flow does not matter.
From the disadvantages of this type of power plants, one can distinguish a complex design and difficult installation.
Advantages of mini hydro power plants
Regardless of the type of design, mini-hydro power plants have a number of advantages:
- Environmentally friendly, do not produce harmful substances for the atmosphere.
- The process of generating electricity is noiseless.
- Water stays clean.
- Electricity is generated all the time, regardless of the time of day or weather conditions.
- Even a small stream is enough to equip the station.
- Surplus electricity can be sold to neighbors.
- Don't need much permit documentation.
DIY Mini Hydro Power Plant
You can build a water station to generate electricity yourself. For a private house, twenty kilowatts per day is enough. Even a do-it-yourself mini-hydroelectric power station can handle this value. But it should be remembered that this process is characterized by a number of features:
- Precise calculations are difficult to make.
- Dimensions, the thickness of the elements is selected "by eye", only empirically.
- Improvised structures lack protective features, resulting in frequent breakdowns and associated costs.
Therefore, if there is no experience and certain knowledge in this area, it is better to abandon the idea of this kind. It may be cheaper to purchase a ready-made station.
If you still decide to do everything with your own hands, then you need to start by measuring the speed of the flow of water in the river. After all, it depends on the power that can be obtained. If the speed is less than one meter per second, then the construction of a mini-hydroelectric power station in this place will not justify itself.
Another step that should not be omitted is the calculations. It is necessary to carefully calculate the amount of costs that will be spent on the construction of the station. As a result, it may turn out that hydroelectric power is not the best option. Then you should pay attention to other types of alternative electricity.
Mini hydropower plant could be the best cost saving solutionfor electricity. For its construction, it is necessary to have a river near the house. Depending on the desired characteristics, you can choose the appropriate version of the hydroelectric power station. With the right approach, you can even make such a structure with your own hands.
