PRINCIPLES OF OTEC PLANT OPERATION
To know about the principle of OTEC plant operation first of all we will know about OTEC plant,and ocean temperature difference.
OTEC or ocean thermal energy thermal conversion is a technology which converts solar radiation absorbed by the oceans to electric energy. The ocean’s can be considered as the world’s largest solar energy collector as it covers two third of the earth surface.
OCEAN TEMPRATURE DIFFRENCE:
There is different temperature in the different layers of the oceans. This is because of the heat input from the sun at the surface of ocean. The surface at the top of the oceans are warmest and gradually the temperature decreases with in depth. But in the polar regions the temperature at the surface of ocean is low,so there is no gradual change in temperature.
PRINCIPLES OF OTEC PLANT OPERATION:
The working principle of an OTEC plant is that it uses the warm water to heat and vaporize a liquid ( working fluid).And this working fluid develops pressure which forces it to evaporate.and the expanding vapour runs through a heat engine like turbine, generator, and it is condensed back into a liquid by cold water brought up from depth and the cycle is repeated.
As we know that water is not perfectly transparent nearly all sunlight is absorbed in the surface layer which heats up. As warm water raises and cold water sinks so this warm water stays near the ocean’s surface. Now Wind and waves circulate the water in the surface layer distributing the heat within it to some extend, and the temperature may remain quite uniform for the first hundred metres, but below the mixed layer the temperature drops very rapidly, perhaps 20 degrees Celsius with an additional of 150 m depth. This area of rapid transition is called thermocline and below it the temperature continues to drop with depth but very gradually.
Genrally thermocline varies with latitude and season but it is permanent in the tropics, variable in the temperate climates is strongest during the summer and is weak to nonexistent in the polar regions where the water is cold from the surface to the bottom.
There are basically three types of OTEC power plant:
- Closed cycle
- Open cycle
- Hybrid cycle
1-What are OTEC power plant?
2-What is ocean temperature difference?
3-Write down the principle of OTEC plant operation?
4-Write different types of OTEC power plant?