This IIT Madras team, part of a global network of researchers, is close to creating a desalination model that can clean drinking water to coastal areas, especially in the aftermath of a natural disaster or flood. The system uses wave energy and the pressure it generates to turn seawater into water that is drinkable and clean.
Researchers have been working on developing desalination techniques for quite some time and the recent success of an IIT Madras team in collaboration with the University of Hawaii in Honolulu, US and Uppsala University, Sweden has made us all proud. The team has won the first two phases of the 'Waves to Water Prize' in a contest organised by the US Department of Energy. What is more exciting is that it aims to provide potable water to coastal flood-hit areas and this is set to be a game-changer.
The objective was to design a wave energy-based desalination system to provide post-disaster drinking water supply to coastal areas. The researchers from the three varieties — Team 'Nalu e Wai' — are working on a small-scale wave-powered desalination system that is rapidly deployable. Deploying a substantial number of these devices in water-scarce regions could produce life-changing results for water-starved coastal communities.
So, how does the system work? "The wave energy system is like a flat plate placed vertically on the seabed. The edge touching the seabed has hinge-like those in doors. The top plate portion can move in both directions when waves pass over the plate. The plates are made in such a way that its top portion does not get submerged (so that the plate always remain upright). Once the plate moves forward and backwards, a piston and cylinder-like door dashpot take the force from the plate. The force finally produces pressurised water," said Dr Abdus Samad, Associate Professor, Department of Ocean Engineering, IIT Madras. "The pressurised seawater (salty) is then passed through a RO (reverse osmosis) system. In our domestic water purifier, we have an RO module and pressure comes from a pump run by electricity. In our case, it is the flat plate which creates pressure," he explained.
Dr Samad said that their team at IIT Madras is working on a wave energy system design and desalination system design — mechanical design, mathematical calculation, piping design, system integration — in the project, while the USA team works on wave interaction with the plate, interacting with USA government etc. Uppsala University works on environmental aspects. "We have more than 50 per cent of the workforce in India. 80 per cent of the team are PhD holders," he added. Dr Samad has wave energy expertise while Dr Abhijit Chaudhuri has desalination expertise. Both are leading the Indian team in the respective areas.
But when will the system be ready to use? "The work is going on, I hope within a year we will be able to demonstrate the full-fledged system in a wave energy test site. This system is portable and modular, if any coastal disaster takes place, we will be able to deliver potable water within a short time to the affected people. We are making the system simple so that the local (coastal) people can assemble and disassemble," he added.
