Tidal energy: the energy possessed by the periodic fluctuation of seawater. The water level difference is expressed as potential energy, and the speed of the tidal current is expressed as kinetic energy. Both types of energy can be used and are a kind of renewable energy.
There is huge energy in the ocean tides. In the process of high tide, the surging sea has great kinetic energy, and as the water level of the sea rises, the great kinetic energy of the seawater is converted into potential energy; in the process of low tide, the seawater rushes away, and the water level gradually decreases, The potential energy is transformed into kinetic energy. The largest value of the tidal range in the world is about 13-15m, but generally speaking, the average tidal range above 3m has practical application value. Tidal energy varies from place to place, and different areas often have different tidal systems. They all obtain energy from deep-sea tidal waves, but they have their own unique characteristics. Although the tides are very complicated, the tides in any place can be accurately forecasted. The main way to use tidal energy is to generate electricity. Tidal power generation uses favorable terrain such as bays and estuaries to build water dikes and form reservoirs to facilitate the accumulation of seawater. Hydroelectric power plants are built on or near the dam to generate electricity through hydroelectric generator sets.
Power generation principle: The main principle of tidal power generation is to use the kinetic energy of the horizontal flow of seawater caused by the tidal force of celestial bodies to produce electricity.
Qualified:
Two physical conditions must be met for the use of tidal power generation.
First, the tide must be large, at least a few meters.
Second, the topography of the coast must be able to store a large amount of seawater and be able to carry out civil works.
The difference with wave energy:
Wave energy refers to the kinetic energy and potential energy of waves on the ocean surface. Wave energy is the most unstable energy source among marine energy sources. Wave energy is produced by the wind transferring energy to the ocean, and it is essentially formed by absorbing wind energy. The rate of energy transfer is related to wind speed, and also to the distance of interaction between wind and water (ie, wind zone). When the water mass is displaced relative to the sea level, the wave has potential energy, and the movement of the water mass point makes the wave have kinetic energy. The stored energy is dissipated through friction and turbulence, and the dissipation speed depends on the wave characteristics and water depth.