Hydroelectric Power Plant
A hydroelectric power plant is a set of hydraulic engineering works located in a certain succession, together with a series of suitable machines. The objective of a hydroelectric power plant is to obtain electricity from the potential energy of moving bodies of water. This is what is called hydraulic energy.
The energy produced by hydroelectric plants must be classified in all aspects as renewable energy because, at least in theory, water can be reused endlessly for the same purpose without undergoing a purification process. The concept of renewability is subordinated to the constancy of the annual volume of total entries.
The hydroelectric plants have the particularity of being activated and deactivated in a few minutes with the immediate opening of the hydraulic gate valves, which offers the possibility of easily covering the sudden peaks of electricity demand that may occur. On the contrary, most thermoelectric plants and nuclear power plants have longer activation times, necessary to heat the water and, therefore, are a type of "always on" (or "basic") plants.
Advantages of hydroelectric power plants
- Economic. The main advantage of hydroelectric power is the elimination of the cost of fuel. The operating cost of a hydroelectric plant is almost immune to increases in the costs of fossil fuels, such as oil, natural gas or coal. Fuel is not necessary and does not need to be imported. The cost of labor in general is low, since the plants are automated and have little staff during the operation. A hydroelectric power station can be established with relatively low construction costs, providing a useful source of revenue to offset the base operating costs.
- Emissions of greenhouse gases. Since fossil fuels are not consumed, carbon dioxide emissions from fuel combustion do not take place. At least, some CO2 emissions occur during the manufacture and construction of the project. It is a small fraction of the operation equivalent to fossil fuel emissions during the generation of electricity.
- Related activities. Bases created by the hydroelectric plans sometimes offer facilities for water sports, becoming tourist attractions in themselves. In some countries the raising of fish on bases is common. From the multiple uses of dams for installed irrigation, it can support the establishment of relatively constant cultivation with the water reach.
Large hydroelectric dams can control floods, which otherwise affect the people living near these projects.
Disadvantages of hydroelectric power plants
One problem related to hydroelectric power plants is the progressive burial in which the accumulation basins inevitably meet over time. To avoid this, these must be dredged periodically.
Environmental problems can be constituted by the fact that barriers (dams) block the transport of river solids (sand and gravel) by altering the balance between solid supply and erosive activity in downstream waters (erosion of the bed of the river and, sometimes, "cut meanders" for greater speed) to the sea where, due to the reduced or no solid contribution, there is the phenomenon of coastal erosion.
In addition, large hydroelectric basins can in some cases have environmental and socioeconomic impacts of different magnitude or severity in the surrounding areas (landscape modification and destruction of natural habitats, population displacements, loss of agricultural areas, etc.) and study of The feasibility must be particularly precise, especially with respect to the precise analysis of the geology of the slopes and the "shoulders" on which the dam will settle, without neglecting any detail. Only in this way can we avoid tragedies such as the Vajont Valley, which in the autumn of 1963 canceled the city of Longarone and two other centers in the valley, causing victims in 1970.
Many of these environmental problems do not occur in "MINI-HYDRO" systems, which in most cases do not require the construction of dams.
Last review: March 25, 2018