From UPSC perspective, the following things are important :
Prelims level : OTEC technology
Mains level : Renewable Energy in India
The National Institute of Ocean Technology is establishing an Ocean Thermal Energy Conversion (OTEC) plant with a capacity of 65 kilowatts (kW) in Kavaratti, the capital of Lakshadweep.
What is OTEC Plant?
- Ocean thermal energy conversion (OTEC) is a process or technology for producing energy by harnessing the temperature differences (thermal gradients) between ocean surface waters and deep ocean waters.
- Energy from the sun heats the surface water of the ocean.
- In tropical regions, surface water can be much warmer than deep water.
- This temperature difference can be used to produce electricity and to desalinate ocean water.
How do they work?
- The OTEC technology uses the temperature difference between the cold water in the deep sea (5°C) and the warm surface seawater (25°C) to generate clean, renewable electricity.
- The technology requires a minimum of 20°C difference between the surface and deep ocean temperatures.
- Warm surface water is pumped through an evaporator containing a working fluid. The vaporized fluid drives a turbine/generator.
- The vaporized fluid is turned back to a liquid in a condenser cooled with cold ocean water pumped from deeper in the ocean.
- OTEC systems using seawater as the working fluid can use the condensed water to produce desalinated water.