Hydroelectric energy can be considered a derivative form of solar energy, as it is closely linked to the regime of precipitation, the ablation of glaciers and in general the water cycle.
From a physical point of view, this technology uses the potential energy of water which, when converted into kinetic energy, can be used to power turbines equipped with an electric generator. In mountain regions, the difference in height between the collection basin located at the top and the positioning of the turbine at a lower altitude is exploited. To exploit the hydrostatic pressure, the pipeline that leads the water from the collection basin to the turbine is usually of the closed type (piping) or obtained in an underground tunnel. Hydroelectric energy can also have other applications, not just mountain ones. In fact, unlike what is commonly imagined, a hydroelectric plant does not always require high waterfalls and large bodies of water. A further advantage of this technology is its availability on command: the collection basin acts as an “electric battery” or accumulator, from which it is possible to take energy when you really need it.
Types of hydroelectric systems
Regulated outflow systems.
They are plants with a natural (lakes) or artificial reservoir, they are the most common, however having a significant environmental impact, as the capacity of the basin is increased with the increase of barriers (dams). Generally these plants are greater than 10 MW of power.
- Storage systems.
- Flowing water systems.
- Plants inserted in water pipes.
In particular, the micro-hydro is an interesting system for recovering energy on a small scale and includes plants below 100kW of power. With small differences in altitude and minimum flow rates it is possible to obtain energy. The systems have small sizes and are easy to install. The advantage of these very small systems is the unnecessary authorization to withdraw water and a non-existent environmental impact.