Current energy

current energy is another kind of ocean energy that appears in the form of momentum energy. The so-called current mainly refers to the more stable flow of seafloor water and the channel and the regular flow of sea water due to tides. One of these is the seawater loop, which refers to the long-distance flow of large amounts of seawater from one sea to another. This sea current is usually caused by two factors: first, the sea surface blows year-round in the direction of the wind, such as the southern side of the equator blowing the same south-easterly wind, while the north side is the same north-easterly wind. The wind blows the sea water, making the surface of the water move, and the dynamics of the water spread this movement to the depths of the sea water. As the depth increases, the rate of sea water flows less, and sometimes the direction of flow changes gradually with the depth, even if the lower sea water flows in the opposite direction to the surface sea water. In the north and south halves of the Pacific and Atlantic Oceans and in the southern half of the Indian Ocean, the dominant wind system creates a vast, counter-clock-turning sea current. At low and mid latitudes, wind is the main driving force for the formation of currents. Second, the temperature and salinity of sea water in different sea areas are often different, they affect the density of sea water. The higher the temperature of the sea water, the lower the salt content, the lower the density of the sea water. The difference in the density of seawater in these two adjacent waters can also cause seawater to flow around. The flow of seawater produces great energy. It is estimated that global currents can reach up to 5TW. The energy of the current energy is directly related to the square and flow of the flow rate. Compared with waves, the change of current energy is more stable and regular. Tides can change size and direction twice a day as tides rise and fall. Generally speaking, the current energy of a water channel with a maximum flow rate of 2m/s or more has the value of actual development.


The theoretical estimate of the world's current energy is
10
8
kW magnitude. Using various observational and analytical data from 130 watercways and navigational doors along the coast of China, the average annual power theory value of
stattation
was calculated to obtain the annual average power value of china's coastal current energy of about 1.4x10
7
kW. Among them, Liaoning, Shandong, Zhejiang, Fujian and Taiwan coastal current energy is relatively rich, the energy density of many watercways is 15 to 30kW/m
2
, with good development value. It is worth pointing out that China's current energy belongs to one of the world's most power density areas, especially in Zhejiang's Zhoushan Islands Jintang, Turtle Mountain and Xihemen watercway, the average power density of more than 20kW/m
2
, the development environment and conditions are very good.