National Institute of Ocean Technology to set up green, self-powered desalination plant in Lakshadweep

Source: The post is based on the article “National Institute of Ocean Technology to set up green, self-powered desalination plant in Lakshadweep” published in The Hindu on 17th March 2023

What is the News?

Chennai-based National Institute of Ocean Technology (NIOT) has set up Low-temperature Thermal Desalination (LTTD) plants in Lakshadweep.

What is Low-temperature thermal desalination(LTTD)?

LTTD is a desalination technique for the conversion of seawater to potable water.

This technique works on the principle that water in the ocean 1,000 or 2,000 feet below is about 4º C to 8º C colder than surface water. So, salty surface water is collected in a tank and subject to high pressure (via an external power source). 

This pressured water vapourises and is trapped in tubes or a chamber. Cold water plumbed from the ocean depths is passed over these tubes and the vapour condenses into fresh water and the resulting salt is diverted away.

What is NIOT planning to do now?

Currently, the desalination plants, each of which provides at least 100,000 litres of potable water every day, are powered by diesel generator sets.

The need for diesel power to reduce the water pressure means that the process is not fossil-fuel-free.

Also, diesel is a precious commodity in the islands as it has to be shipped from the mainland critical for powering the electric grid.

NIOT is now working at making this process free of emissions.