Researchers look into futuristic ideas like atmospheric water, rain energy

New Delhi: When changing climatic conditions, increasing heat waves and other extreme weather events have challenged the availability of fresh water, experts advocate going beyond the conventional for futuristic solutions.

On March 22, as the UN World Water Day focuses attention on the importance of fresh water, here are a bunch of stakeholders who are looking at the futuristic solutions that stand out for their disruptive ideas in the country perennially battling water scarcity with less than three per cent land mass global share against the 18 per cent of population.

Dr Visakh Vaikuntanathan, Assistant Professor, Department of Mechanical Engineering, Shiv Nadar University, Delhi–NCR, and his team have been working on a novel concept of harnessing rain energy by quantifying the amount of energy contained in rainfall of different intensities, light, medium, heavy, extremely heavy etc.

“The energy 'lost' in the form of sound when rain impacts on surfaces is palpable,” says Vaikuntanathan and explained the challenges in the process of harvesting this energy, which differs with the type of rainfall.

His team says the 'all-weather' cells – which work as a 'solar cell' when the sun shines and as a 'rain cell' when it is rainy – can be integrated with rooftops, sidewalks, drainage systems etc. to extract energy from raindrops as well as water flow in existing rainwater harvesting systems.

With rainfall data from the India Meteorological Department (IMD), the team calculates the average rainfall rate, expressed in mm/hour. “Next, we employ fluid mechanical models reported in the scientific literature on the relationship between rainfall rate and raindrop size distribution, to estimate the amount of kinetic energy contained in the raindrops within a particular rainfall,” he says.

“Ongoing studies are focused on improving this framework for estimating the rain energy contained in different rainfall types, and creating a rain energy map based on the rainfall data,” Vaikuntanathan adds.

Going beyond conventional sources, such as the fast-depleting groundwater or surface water, atmospheric water harvesting and generation are some of the innovative solutions being implemented.

A paper in the journal Nature earlier in the month points out how a sorption-based atmosphere water harvesting (SAWH) irrigation system can “revolutionise agriculture, making it geographically and hydrologically independent”.

However, not just for irrigation, atmospheric water generation can be an eco-friendly and reliable drinking water solution for industries, corporates, and communities using innovative technology, says Navkaran Singh Bagga, CEO and founder of Akvo Atmospheric Water Systems.

His company is into atmospheric water generation in 15 countries using sustainable water technology, in this case, tapping the atmospheric humidity.

It recently announced the commercial launch of its Water-on-Want (WoW) initiative for corporates in Tamil Nadu, Karnataka, Maharashtra and Gujarat.

Bagga says, “The minimum daily offtake is 500 litres per day (LPD) and it works on OPEX BOOT (Build Own Operate Transfer) model with no initial cash investment.” Technology is helping in other ways too and is especially useful in assessing and analysing the Himalayan glaciers situated in remote, high-altitude areas.

The glacier and snowmelt constitute 30 to 40 per cent of the annual water flow of the mighty rivers originating in the upper Himalayas, which are intricately linked to the groundwater of the river floodplains.

Reminding that the theme of this year's World Water Day is 'Glacier Preservation', Dr Dipankar Saha, Chair Prof, Centre for Advanced Water Technology and Management (CAWTM) at the Manav Rachna International Institute of Research and Studies (MRIIRS), says: “In the Gangetic plains flanked by Himalayas in the north, climate change is impacting glaciers and in turn imposing uncertainty in downstream river flows and aquifers. The situation needs urgent action.” Even in the field of glaciers, technology plays a vital role. “With glacial changes accelerating, a combination of early warning systems, controlled drainage techniques, and community preparedness programmes is essential to reducing disaster risks,” says Suhora, a tech company that is actively working on refining downstream solutions.

It combines satellite intelligence, sensor-based monitoring, and predictive analytics, to mitigate the threats posed by these changes with a dedicated system to transform satellite data into actionable insights to address global security, disaster response, and environmental challenges, says a statement from the company.

A 2018 NITI Aayog report had drawn attention to the worsening water crisis and how by 2030, India's water demand was projected to be twice the available supply leading to a severe water crisis for crores of people and a striking potential 6 per cent loss in GDP.