Every Mechanical Engineering student is taught the ‘Rankine Thermodynamic cycle’, that is basically the way water at the air surface evaporates due to solar energy, then gets condensed after reaching a certain height where the temperature is low, hangs in the air and moves with the wind, what is known as the “Monsoon” in Southeast Asia, and then condenses to become water again and falls as rain. Can this condensation process of the air vapor content be regulated in a controlled manner?
This excited engineers in the last ten years to work out why we should not extract water hanging in the air, based on a compression reverse cycle, rather than waiting for the rains to happen and thereby create a solution for different world areas where conventional water sources are insufficient, or too contaminated to be safely used. My friend, M. Ramkrishna, has been one amongst these engineers.
Maithri Aquatech focused on this technology in 2016. There were many groups working on it and there was no standardized process. The only evaluation parameter found was a sort of specific energy consumption. The extraction of water from air is innately exothermic, involving phase change from vapor to liquid. Maithri got down to define hypotheses about Indian environmental conditions leading to a good design and in the process, standardized the Atmospheric Water Generator (AWG) thermodynamic cycle. The Company received able support and inputs from Indian Institute of Chemical Technology and TERI: Innovative Solutions for Sustainable Development gave them the needed impetus and they now have water energy transformation coefficients for all major climatic zones in India.
Maithri made power consumption in the compressor the prime design criterion. Based on the models of humidity in the atmosphere representing mass and energy conservation, they worked with evaporation and condensation isobaric curves and arrived at thermodynamic airflow conditions and mass flow entity, for example. The rest was getting the right components and system integration. Bharat Electronics Ltd., India’s principal manufacturer of electronic systems joined us as our production partner. Maithri’s AWG – MEGHDOOT – is the first AWG machine in the world designed for reverse cycle efficiency by optimizing the Energy Efficiency Ratio (EER) and the Coefficient of Performance (COP).
Then the coronavirus pandemic struck in the beginning of 2020. The protracted lockdown and disruption of industrial supply chain created a new normal for both life and businesses. The disruption would continue for a while, but it also brought in the need to differentiate drinking water from the water used for cooking and other general purposes like bathing, washing clothes and cleaning. Having an AWG in every house for safe drinking water is emerging as the new normal as bottled water and RO water are simply unviable. As W. H. Auden famously said, “Thousands have lived without love, not one without water.” Let us draw from air your drinking water as our ancestors drew it from the “family well.”
Prof. Arun Tiwari Profile:
Professor Arun Kumar Tiwari is an Indian missile scientist, author, and professor. He has written several books and co-authored 5 books with Dr. APJ Abdul Kalam, including Wings of Fire, the autobiography of Dr. APJ Abdul Kalam, former president of India. Wings of Fire, published in 1999 and Transcendence: My Spiritual Experiences with Pramukh Swamiji are considered modern classics. Both the books have been translated in multiple Indian languages and read by millions of readers.
Prof. Arun Tiwari works as Adviser at Telecommunications Consultants India Limited, New Delhi. He is a Platinum Jubilee Mentor of CSIR-Indian Institute of Chemical Technology, Hyderabad; Director Care Foundation, Hyderabad; and teaches at School of Management Studies in Hyderabad University as Adjunct Professor.