Published on: June 10, 2021



What is in news : Narippaiyur, a village in Ramanathapuram District, a drought prone area situated in the South-East corner of Tamil Nadu will benefit from 20,000 litres per day of fresh water produced from sea water – thanks to the solar thermal Forward Osmosis (FO) sea water desalination system installed in the place.

Details :

  • The customized demand driven convergent water solution through FO will supply two litres of good quality drinking water per person per day for 10,000 people in the village, successfully overcoming a major drinking water shortage in the village.
  • Tamil Nadu IIT Madras in collaboration with Empereal – KGDS Renewable Energy have successfully established and demonstrated this system to address prevalent and emerging water challenges in Mission Mode in the village.


  • Forward Osmosis (FO) over the past five years has generally attracted more attention, both academically and commercially, with a number of companies raising finance on the back of its potential.
  • The process exploits the natural process of osmosis, which is how plants and trees take up water from the soil – a low energy, natural process. It works by having two solutions with different concentrations (or more correctly different osmotic pressures) separated by a selectively permeable membrane, in the case of the plants and trees their cell walls, and ‘pure’ water flows from less concentrated solution across the membrane to dilute the more concentrated solution, leaving the salts behind.
  • The clue in the potential applications is that it is widely used in nature, however it is only relatively recently that its full potential has begun to be recognised industrially. It can be used on its own or in combinations with other processes, for example desalination, concentration and renewable power generation.