What Is a Hydroelectric Plant?

A hydroelectric power station is a power station that uses the kinetic energy of the powerful current produced by the water level difference to generate electricity, referred to as "hydropower station" for short. Industrial enterprises that use water energy from rivers to drive turbines to generate electricity. Advantages: no fuel, low cost, no environmental pollution, simple manufacturing of electromechanical equipment, flexible operation, etc. At the same time, power generation hydraulic structures can be combined with flood prevention, irrigation, water supply, shipping, breeding and other undertakings to implement comprehensive utilization of water resources. Disadvantages: large capital investment, long construction period, limited by natural conditions, etc. ^[1]

A hydroelectric power station is a power station that uses the kinetic energy of the powerful current produced by the water level difference to generate electricity, referred to as "hydropower station" for short. Industrial enterprises that use water energy from rivers to drive turbines to generate electricity. Advantages: no fuel, low cost, no environmental pollution, simple manufacturing of electromechanical equipment, flexible operation, etc. At the same time, power generation hydraulic structures can be combined with flood prevention, irrigation, water supply, shipping, breeding and other undertakings to implement comprehensive utilization of water resources. Disadvantages: large capital investment, long construction period, limited by natural conditions, etc. ^[1]

Chinese name

Hydroelectric power station

Foreign name

hydroelectric station

Basic principles of hydropower stations

Hydroelectric power is the use of hydraulic power (with water head) to drive a hydraulic machine (turbine) to turn, transforming the potential energy of water

For mechanical energy, if another type of machine (generator) is connected to the water turbine, it can generate electricity as the water turbine rotates. At this time, the mechanical energy is converted into electrical energy. In a sense, hydropower is the process of converting the potential energy of water into mechanical energy.

Comprehensive engineering facility to convert water energy into electricity. Also called a hydropower plant. It includes a series of hydropower station buildings and various hydropower station equipment built to produce electricity from water energy. Use these buildings to concentrate the drop of natural water flow to form a water head, collect and regulate the flow of natural water, and send it to the turbine. The combined operation of the turbine and the generator converts the concentrated water energy into electrical energy, which is then passed through a transformer, a switch Stations and transmission lines, etc., feed electrical energy into the grid. In addition to the buildings required for power generation, some hydropower stations often have other buildings that serve comprehensive purposes such as flood control, irrigation, shipping, wood crossing, and fish crossing. The complex of these buildings is called a hydropower or water conservancy hub.

Classification method of hydropower station

There are various classification methods for hydropower stations. According to the nature of water used by hydropower stations, it can be divided into three categories. Conventional hydropower stations: use natural rivers, lakes, and other water sources to generate electricity; Pumped storage power stations: use excess power at low loads in the power grid to pump water from low reservoirs to high places, and store water in stocks, and wait for power grid peaks Discharge water to generate electricity, and tail water to the lower reservoir, so as to meet the needs of power loads such as power grid peak regulation; Tidal power station: use the tidal energy generated by the tide fluctuations to generate electricity.

Hydropower stations can be divided into two categories according to their use and regulation of natural water flow. Runoff-type hydropower station: there are no reservoirs or reservoirs with small storage capacity and no capacity to regulate or regulate natural water; Water-storage hydropower stations: Hydropower stations with a certain storage capacity and different capacity to regulate natural water flow.

In the construction of hydropower stations, the following classification methods are often used. According to the development mode of hydropower stations, that is, the method of centralized water head and the hydropower station's engineering layout, it can be divided into three basic types: dam hydropower station, diversion hydropower station and dam-diversion hybrid hydropower station. This is the most common classification method in engineering construction. According to the size of the hydropower station, it can be divided into high-head, middle-head and low-head hydropower stations. There is no uniform regulation on the specific division of water heads in the world. Some countries use low head hydropower stations with heads below 15m, medium head hydropower stations from 15 to 70m, high head hydropower stations from 71 to 250m, and extra high head hydropower stations with heads greater than 250m. China usually refers to a high-head hydropower station with a head of more than 70m, a low-head hydropower station of less than 30m, and a medium-head hydropower station of 30 to 70m. This classification standard is more suitable for the classification of the main buildings of hydropower stations and the scope of application of the classification of hydroelectric generating units. According to the installed capacity of hydropower stations, it can be divided into large, medium and small hydropower stations. Countries generally designate hydropower stations with installed capacity below 5000kW as small hydropower stations, 5,000 to 100,000 kW as medium-sized hydropower stations, 100,000 to 1 million kW as large hydropower stations, and more than 1 million kW as giant hydropower stations. China stipulates that hydropower stations are divided into five classes, among which: installed capacity greater than 750,000 kW is first-class [large (1) -type hydropower station], 750,000 to 250,000 kW is second-class [large (2) -type hydropower station], 250,000- 25,000 kW is third-class [medium-sized hydropower station], 25,000 to 0.05 million kw is fourth-class [small (1) hydropower station], and less than 0.05 kW is fifth-class [small (2) hydropower station]; Below 12,000 kW as a small hydropower station. ^[2]

Hydroelectric power station

China has built various conventional hydropower stations such as the Three Gorges, Gezhouba, Wujiangdu, Baishan, Longyangxia and Yili River cascades, large pumped storage power stations such as Panjiakou (see Panjiakou Water Conservancy Hub), and experimental Jiangxia tides Power station.

Development analysis of hydropower stations

In the 30 years since China introduced reform and opening up at the end of 1978, with the rapid development of the country s economy and society and the continuous deepening of reforms, China s hydropower development has successively solved the constraints of technology, capital, market, and system. The rate of doubling in the year has made remarkable achievements.

In 2007, China's hydropower development boom surged, showing a booming scene. In particular, the successful closure of the Xiluodu Hydropower Station on the Jinsha River indicates that China's hydropower development is on a new journey. By the end of 2007, China's total installed hydropower capacity reached 145 million kilowatts, accounting for approximately 20.3% of the total capacity, an increase of 11.49% year-on-year. By the end of 2008, the nation s hydropower installed capacity reached 175 million kilowatts, ranking first in the world, accounting for 21.6% of the country s installed power generation capacity, second only to coal-based power generation. Guided by the scientific development concept, China Hydropower has entered a new stage of orderly development and harmonious development. The technical level of hydropower survey and design, scientific research, construction, equipment manufacturing, installation and construction management has leapt to a new level.

In addition, various economic indicators of China's hydropower industry have grown rapidly. From January to November 2007, China's hydroelectric power generation industry realized a total industrial output value of 93,826,334,000 yuan, an increase of 20.88% over the same period of the previous year; a cumulative product sales income of 89,240,772,000 yuan, an increase of 20.17% over the same period of the previous year; cumulative realized profits The total amount was 24,689,815,000 yuan, an increase of 35.91% over the same period of the previous year. From January to November 2008, China's hydropower generation industry realized a cumulative total industrial output value of 111,348,950 thousand yuan, an increase of 23.50% over the same period last year; realized cumulative product sales income of 113,147,151,000 yuan, an increase of 24.80% over the same period last year; realized cumulative profits The total amount was 26,863,763 thousand yuan, an increase of 9.75% over the same period of the previous year.

The significance of hydropower stations

The Chinese economy has entered a new period of development. As the national economy continues to grow rapidly and industrial modernization is accelerating, resource and environmental constraints are tightening, energy supply is tight, and the pressure on the ecological environment continues to increase. According to this, speeding up the development of hydropower resources in the west and realizing the transmission of electricity from the west to the east are undoubtedly of great significance for solving the problem of energy shortage in the development of the national economy, improving the ecological environment, and promoting the coordination and sustainable development of the regional economy. In addition, vigorous development of hydropower will help reduce the gap between urban and rural areas and improve rural production and living conditions. It will have an irreplaceable role in advancing local agricultural production, increasing farmers' income, accelerating the pace of poverty alleviation, promoting national unity, and maintaining social stability. Hydropower development will transform local resource advantages into economic advantages and industrial advantages through investment stimulus, increased taxation, and the development of related service industries. This will drive the development of other industries, form strong supporting industrial clusters, and effectively promote the overall development of local economies. .