Chennai: The city’s ongoing water crisis has not only left people in a fix but has also prompted them to look at sustainable alternatives to produce water. The innovation of IIT-M students named ‘Nero’ – an optimised desiccant solar cell device — comes as a glimmer of hope amidst the current grim situation of acute water scarcity.
The device was developed in collaboration with Teertha, a company based on sustainable technology. It can produce about 6 to 7 litres of potable water per hour and about 180 litres per day and has been installed at the Tiruchy Railway station at a cost of `2 lakhs.
The atmospheric water generator is a coming of age technology which extracts water from the surrounding humid air. It works on the principle of condensation (converting vapour to liquid) and uses desiccants (a substance, usually a solid which absorbs moisture) for trapping water molecules from the air.
‘Nero’ operates by trapping water molecules from the atmospheric air during the night and yields water during the day by utilising solar energy. The device comes with a number of advantages, including very low maintenance and operating costs as it functions entirely on solar-thermal energy and involves no moving parts.
An MoU was signed between by Prof. Ravindra Gettu, Dean (Industrial Consultancy and Sponsored Research), IIT Madras, and Ms Durga Das, Chief Executive Officer of Teerthaa in the presence of Dr M.P. Maiya, Refrigeration and Air Conditioning Laboratory, Department of Mechanical Engineering, IIT Madras, who coordinated the project and Dr S.S. Sivakumar, Mr Jayakar Rao and Mr Iftekhar Pathan, cofounders of Teerthaa on March 6, 2019.
Speaking about the project, Ms Durga Das said, “We are interested in exploring and perfecting different technologies of Atmospheric Moisture Extraction (AME) as a part of our major national mission of availability of potable water for the masses. At present, we are producing AMEs based on vapour compression refrigeration technology in several output configurations. With ‘Nero’ we will bring to light and enhance the lives of millions of homes in the villages where water is scarce. Creating an impact that reaches the masses is a mission very close to our hearts. We brought the first Indian built atmospheric water generator in India 14 years ago and hold a patent for the same. Now we will bring the first solution that will generate4-5 litres of water without any electricity and maintenance free.”
Explaining the technology used in the project Prof M.P. Maiya said, "Atmospheric air is not only a major source of fresh water but also universally available.
However, it is in the form of vapour, and the challenge is to collect it as liquid. The proposed solar still based on desiccant technology traps water molecules from the atmospheric air during the night and yields water during the day by utilizing solar energy. It would be a boon to places where even brackish water is not available. M/s Theerthaa, formerly known as Akash Ganga, has pioneered the technology of extracting water from thin air and delivered systems to 2,800 customers in the past 14 years saving six lakh litres of water every day. It is great that they are diversifying their activity by venturing to this new technology to serve society better with pure drinking water."
Another team from IIT-M is currently working on a similar project to tap water from atmospheric air. The model is set to be tested at Pallavakkam beach, Chennai in a few weeks.
