Hydro power plant
Hydroelectric power plant (HPP) - power station, as energy source which uses the energy ofwater flow. Hydroelectric power stations are usually built on the rivers, building dams and reservoirs.
For the efficient production of hydropower requires two main factors: the guaranteed supply of water all year round and possibly large deviations of the river, Water Engineering favorcanyon views relief.
Principle of operation
The principle of hydroelectric power station is quite simple. The chain of hydraulic structuresprovides the necessary water pressure entering the turbine blades, which drives a generator, producing electricity.
Necessary water pressure generated by the dam, and as a consequence of the concentration of the river at a certain place, or derivation - the natural flow of water. In some cases, to obtain the necessary water pressure is used in conjunction, and the dam, andderivation.
Directly in the building of hydropower stations is all power equipment. Depending on the destination, it has its definite division. In the machine room are hydraulic units, directly converting energy of water flow into electrical energy. There are a various additional equipment, facilities command and control over the work of HPS, transformer station, switchgear and more.
Hydroelectric power depends on the pressure and flow, as well as the efficiency of turbines and generators are used. Because of that the natural laws of the water level is constantly changing, depending on the season, and yet for some reason, as an expression of power hydroelectric stations decided to take the cyclical power. For example, the distinguished annual, monthly, weekly or daily cycles of hydroelectric power.
Depending on the water pressure in the hydro power plants using different types of turbines. For high-pressure - bucket and radial-axial turbines with metal spiral chambers. Medium-pressure hydropower installed Kaplan and radial-axial turbines at low pressure - Kaplan turbine in concrete chambers. The principle of operation of all types of turbines is similar - the water under pressure (water pressure) is applied to turbine blades, which will start rotating. Mechanical energy is thus transferred to the hydrogenerator, which generates electricity. The turbines are different by some characteristics, as well as cameras - a steel or concrete, and are designed for different water pressure.
Hydroelectric stations are also divided according to the principle use of natural resources and, accordingly, the resulting water concentration. Here are the following hydroelectric power stations:
• channel and dam hydropower. This is the most common types of hydro-electric power stations. Water pressure in them is created by installing a dam, blocking the river entirely, or elevating the level of water in it at the desired height. These hydroelectric power built on high-water rivers of the plains, and mountain rivers, in places where the river channel is narrower, compressed.
• hydroelectric dams. Are built with high water pressure. In this case, all partitions off the river dam, and the building is located behind the hydroelectric dam in its lower part. Water, in this case, is supplied to the turbine through special pressure tunnels, but not directly, as in channel hydroelectric power station.
derivational hydro power plants. These power station are built in places where large slope of the river. The required concentration of water in hydropower generated by this type of derivation. Water is removed from the river channel through a special drainage. Last - straight, and their deviation is much smaller than the average slope of the river. As a result, the water is piped directly to the building of hydroelectric power plants. Derivational HPP can be of different types - non-pressure or pressure derivation. In the case of the derivation of pressure, water line is laid with a large longitudinal bias. In another case at the beginning of diversion on the river created a high dam and reservoir is created - this scheme is also called mixed derivation, as used two methods to create the necessary concentration of water.
• pumped storage power station. These PSPs are able to accumulate power generated, and let her move at times of peak loads. The principle of operation of such power stations as follows: in certain periods (not peak), the units operate as pumps PSP on external sources of energy and water is pumped into specially equipped upper pools. When the need arises, the water from them enters the penstock and the turbine operates.
The composition of hydro-electric stations, depending on their destination, and can include additional structures such as gateways or ship lift to facilitate navigation on body of water, fish crossing, water intake structures used for irrigation, and much more.
The value of the hydroelectric station is that for the production of electrical energy, they make use of renewable natural resources. Because the need for additional fuel for hydropower is not the final price of the received electric power is much lower than with other types of power plants.