Prime Minister Narendra Modi speaking at Ramlila Maidan, December 2019. Photo: PTI.
Narendra Modi, the prime minister of India, is being ridiculed again for his statement on water generation using wind turbines. There are certain aspects of technology policy that a prime minister should know, and it is the job of the science and technology advisor to train politicians in such matters. Public comments on such issues should have a more detailed exposition while highlighting the core science, and using credible sources of information.
Technology evolves in phases from conception to the laboratory, followed by field tests and the development of a commercial prototype. The final stage is its implementation, which eventually leads to its market use and adaptability. In the context of emerging technologies that are in the laboratory or field stages of development, a lot of grey areas always remain, and regarding which claims and counterclaims are made, and a lot of promising technologies are found to be mistaken in the long run. In contrast, a lot of technologies that were originally underrated have emerged at the forefront. There is a story that Thomas Watson, the founder of IBM, once said that there is a market around the world for maybe five personal computers!
From the perspective of the basic principles of science, it is possible to use wind turbines to extract water from the air in a limited way. However, the technology has yet to be proven suitable for large-scale field use, and its potential leverage in comparison to other technologies is yet to be established. A company called Eole Water claimed to have made such a prototype, but they did not publish any of their technical papers on the subject and in fact closed shop several years ago.
An article published by CNN in April 2012 trumpeted Eole’s technology and has been doing the rounds since Modi’s comments as proof that the technology works. However, the article does not have any independent comments from other scientists on the topic and presents no independently verifiable information. But till date, there is no evidence of any published scientific paper on this subject, certainly none that can validate Eole’s turbine’s technological potential.
A paper published in the journal Energy Conversion and Management in 2008 describes a complex design – using a solar chimney to extract water from the atmosphere. But the description is mostly theoretical and a turbine itself does not have a direct role in extracting water from the atmosphere.
All this said, in principle, it should be possible to generate water from air using wind turbines, with the help of additional technologies like a means of water absorption or suction, condensation and a means of its collection – and all of which will need large amounts of energy. There are substances called hydrogels, which are cross-linked polymers that can absorb and hold large amounts of water and other aqueous solutions, and the blades of a wind turbine could be covered with such elements. There are also microfluidic devices that have thousands of microchannels, built with materials like polydimethylsiloxane, that can be used for such applications.
However, these are all ideas, and they are in the early stages of development in different contexts. Their large-scale test and implementation within the constraints of present-day engineering and technology have not been validated at a significant scale. And even if technologies could be realised, again in principle, Modi’s idea of generating oxygen using wind turbines would be even more cumbersome to implement, with few benefits of any kind.
Instead, the prime minister should focus on the policymaking aspects while working towards creating a conducive atmosphere for technological development, and refrain from making comments in areas where a deeper level of expertise is needed. Indeed, it is best not to make frivolous comments without feedback from experts in the field or based on a poorly reported article. Statements on key scientific and technological issues should be left to experts with demonstrated expertise.
Dhiraj Sinha has a doctorate in electrical engineering from Cambridge University. He has published papers in the field of microsystems and microfluidics in leading journals.