Hydroelectric power is a source of energy based on harnessing the power of moving water, such as that flowing over a waterfall, to generate electricity. Except for the dry season, these facilities are not dependent on weather conditions to operate properly.
Likewise, the flow of electricity is controllable, so each hydroelectric plant can adapt its production to market demand.
Thanks to its reliability, hydropower is one of the most important renewable energy sources in the world. Beyond generating energy, hydroelectric dams create clean water reserves, facilitate flood control and offer an adequate supply of the vital liquid. You can learn about the advantages and disadvantages of hydroelectric power by clicking here.
Conventional hydroelectric plants are systems that consist of three parts: the power plant, where electricity is generated, the dam that opens or closes to keep the flow of water under control, and the reservoir where the water is stored. But how does this system work? Coming up next, we tell you.
How is electricity generated with hydroelectric power?
Water acquires potential energy
Usually, dams are located in the course of a river, where water accumulates artificially to create the reservoir. Thanks to this initial process, the water obtains potential energy that will later be converted into electrical energy.
For this to be accomplished, the dam should be located as high as possible, while a system of valves controls the entrance of water to the pressure room.
The water falls under pressure and generates the movement of the turbine
The water travels through a pipe or water channel to the hydroelectric system. This process is completed by the action of gravity (fall) or by simple pumping. Subsequently, hydraulic gates are used to send the water to the tanks and turbines of the plant.
The gates are large devices that are installed in the water fall line and allow the liquid to accumulate sufficient velocity to move the turbine blades.
At this point, a filtering system is also enabled to remove any solid element from the water that could impair the movement of the turbine.
The generator transforms potential energy into electricity.
The electric generator, which is connected to the turbine by gears or shafts, is activated by the movement of the blades and transforms the potential energy of water into electrical energy.
The amount of electricity generated depends on the drop distance and the amount of water flowing into the system.
If the water falls from a far enough point (height of the dam), it will have more power and therefore more energy. For its part, the greater the amount of water that enters the system, the more energy it will produce. Thus, larger rivers and currents have greater generation capacity.
The electrical energy is sent to the national electrical network
After electrical energy is generated and converted into alternating current, this is transported via high voltage lines to a substation where the tension or voltage will increase.
Finally, the energy is sent to the huge transmission towers of the national electrical grid, from where the service will be distributed to homes, buildings and businesses.
Once it reaches the communities, the transformation centers reduce the voltage at low or medium voltage so that the energy can be used by people.
The water returns to the river
One of the fascinating aspects of hydroelectric power is that the water is used over and over again. After giving up its energy, the water returns to the river through a special drainage channel.