Need for new tech to tackle water crisis
India is facing an unprecedented water crisis, as by 2050, demand for water is expected to be twice the available water supply (NITI Aayog 2019). In India, out of 734 districts, 256 are water stressed. There are many regions where groundwater is depleting fast. Further, per capita freshwater availability has come down from 5177 cubic metres (1951) to 1465 cubic metres (2024)and is expected to go down further if no actions are taken. With an ever-increasing population and rising industrial demands, traditional water sources are becoming overburdened and insufficient. Recent water crises in Delhi and Bengaluru underscore the urgency of finding alternative solutions. Although pipelines are in place, their functionality remains unpredictable, and the duration of water supply is uncertain.
For example, in Delhi, the average water production is 995 million gallons per day (MGD). However, approximately 58% of this water is lost as ‘non-revenue water’ or ‘unaccounted water’ (leakages in water lines, unauthorised tappings, theft, etc.), leaving only 421 MGD available for consumers. Despite an increase in Water Treatment Plant (WTP) capacity from 650 MGD to 906 MGD between 2006 and 2015, there has only been a 5% increase thereafter from 2015 to 2024. Several metropolitan cities, such as Bengaluru, have experienced severe water shortages, disrupting daily life and economic activities in the recent past. Despite the Bangalore Water Supply and Sewerage Board (BWSSB) charging the highest tariffs nationwide, it still incurs a Rs 390 crore loss annually. Transporting 70% of Bengaluru’s water 100 km from the Cauvery River is unsustainable, and water bodies have dwindled from 1452 to 193 since the 1800s. This calls for alternative solutions for minimising reliance on traditional water resources.
As innovative solutions are sought to address the pressing water scarcity issue, Atmospheric Water Generators (AWGs) have emerged as a promising technology. This works on two basic parameters: humidity and temperature. High temperatures and high humidity serve as ideal conditions for the peak performance of water generators. AWGs extract water from humid ambient air by cooling the air to its dew point, causing water vapour to condense. This water is then collected, filtered, and purified to meet WHO drinking water standards. AWGs are particularly effective in regions with high humidity, such as coastal areas, where they perform with more than 100% efficiency.
AWGs offer numerous benefits: they harness a natural and ubiquitous resource—the air—providing a renewable source of water and reducing dependency on depleting groundwater resources and erratic rainfall patterns, promoting sustainability. Industries can achieve water neutrality by generating water on-site, reducing their water footprint, and contributing to local water conservation efforts, which enhances their brand image and promotes corporate social responsibility. AWGs can be installed in remote and arid areas where conventional water supply infrastructure is lacking or unreliable, ensuring that communities in those regions have access to safe drinking water. In crisis situations, authorities often rely on water tankers, but the quality of tanker water is often suspect. Atmospheric water can improve health outcomes for the population. Furthermore, in disaster-prone areas, AWGs can provide potable water when traditional supply lines are disrupted, offering critical emergency relief.
Select railway stations, including those in Mumbai and Secunderabad, have installed AWGs. Mumbai’s high humidity allows AWGs at railway stations to harness atmospheric moisture to produce substantial amounts of water daily, dispensed through hygienic and user-friendly vending machines. The Secunderabad railway station similarly benefits from AWGs, providing a reliable source of clean water to commuters every day. In several urban parks, AWGs are integrated with existing infrastructure to provide hydration points for joggers and visitors.
The Ministry of Jal Shakti has approved AWGs as a recommended innovative technology for enhancing water resource availability. Adopting AWGs represents a significant stride towards addressing India’s water scarcity challenges. By providing a sustainable and reliable source of drinking water, AWGs contribute to the nation’s water security goals. For localities or industries requiring more water, multiple strategically located AWG systems may be used. This ensures at least some water availability in case of a breakdown, as the chances of all units failing simultaneously are low.
To maximise the utility of AWGs across geographies, steps must be taken to reduce the costs of AWGs for wider adoption, create awareness about the benefits, and offer upgradation and customisation in systems for different climatic conditions.
A diverse array of stakeholders — including state and central government departments, industries, PSUs, research and academic institutions, NGOs/CSOs, businesses, places of worship, ship ports, airports, railway stations, bus stations, health care centres, remote defence training facilities and camps, lighthouses, telecommunication towers, electric substations, prisons, and individuals — may be encouraged to adopt this technology to address water demand effectively.
(S K Sarkar is Distinguished Fellow, The Energy and
Resources Institute (TERI) and former Secretary, Ministry of Water Resources, Govt. of India; Priyanka Vadrevu, Research
Associate, TERI)