Context :- National Institute of Ocean Technology to set up green, self-powered desalination plant in Lakshadweep.
- Currently the National Institute of Ocean Technology (NIOT) is providing potable water in 6 islands of Lakshadweep.
- It uses Low Temperature Thermal Desalination (LTTD) technology powered by diesel generator sets.
- Each plant provides at least 100,000 litres of potable water every day.
- The plants are funded by the Lakshadweep administration.
- The Ministry of Earth Sciences (MoES) provides technical assistance.
- The proposed self-sustaining plant is the 10th plant in Lakshadweep and is expected to be ready later this year.
- The desalination plant will also supply power to the plant, thus fossil-fuel free and self-powered.
The NIOT is an institute under the aegis of the Ministry of Earth Sciences (MoES), which works on harnessing energy from the ocean including ocean thermal technology.
Low Temperature Thermal Desalination (LTTD)
- LTTD exploits the difference in temperature (nearly 15°C) in ocean water at the surface and at depths of about 600 feet.
- The warmer water’s (at the surface) pressure has been lowered using vacuum pumps.
- The cold water at the depth condenses the warmer water at the surface.
- Such de-pressurised water can evaporate even at ambient temperatures.
- This resulting vapour when condensed is free of salts and contaminants and fit to consume.
- Advantage – This technology does not require any chemical pre and post-treatment of seawater.
- It does not require effluent treatment.
- It gives less operational maintenance problems compared to other desalination processes.
The Reverse Osmosis, a globally accepted technology suitable for desalination of saline water, is a membrane process which is quite different from LTTD technology.