Description
Half of the world's population could be living in water-scarce areas by 2025, according to a United Nations report. India, where groundwater is essential for food security and consumption, is already dealing with declining groundwater levels. This alarming trend highlights the urgent need for sustainable water solutions in India and around the world. (ALSO READ: There Will Be Tomorrow If There Is Water, Says Modi Throwing Jal Jan Abhiyan) One of these solutions is to extract water from the air around us. Air water? It may sound like science fiction, but innovators are touting this unconventional method of water extraction as a potential answer to help solve the problem of water scarcity around the world. (READ ALSO: Google doodle for 'Earth Day 2023' outlines an action plan for a greener future) A water-to-air extraction system uses a dehumidifier to remove moisture from the air. This can be done in a number of ways, the most common being cooling the warm, humid air. Through this process, the air loses its ability to hold moisture, causing water vapor to condense into droplets. Something similar can be seen while we are running our air conditioning.
A Bangalore-based start-up, Uravu Labs, has created a device to capture water from the air. However, they took a different approach. They used a desiccation-based air and water extraction system where a saltwater solution called brine is used to remove moisture from the air. Air passes over the brine, and as it absorbs moisture, the brine becomes saturated. The brine is then heated by solar energy to evaporate the water and the resulting water vapor is collected.
You can relate the water absorption to household salt that becomes wet and sticky during the rainy season.
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While Uravu Labs currently uses solar power, Shrivastav says his device can run on waste heat from industries and biomass.
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Uravu Labs supplies bottled water to the hospitality industry, premium cafes and the beverage industry from an in-house facility based in Bangalore. Its current capacity is 1000 liters per day (LPD), with an average cost of Rs 4-5 per liter of water produced. They have an ambitious target of moving to 1 lakh LPD within two years and expect lower costs.
Since the device draws water from the air, it requires climatic conditions with sufficient humidity. This may not work in cold, dry climates, while higher humidity also presents a challenge.
To solve this problem, Shrivastav says they can change the amount of brine to accommodate changes in relative humidity without increasing operating costs.
However, the device requires a temperature of more than 12 to 15 degrees Celsius and a relative humidity of more than 25 to 30 percent, Swapnil adds.
But while water is chemically dihydrogen monoxide (H20), our bodies need water that contains minerals and soluble salts. Also, air pollution can end up in the dehumidified water.
On this, Swapnil says his current target customers are those who require pure water, such as the beverage industry, while also being able to mineralize the water based on customer needs. He also claims that his device can filter contaminants in the air.
The cost, size of the device, maintenance requirements, and environmental concerns of proper desiccation disposal are other challenges that can make widespread use of this type of air and water removal system difficult.
The Central Ground Water Board (CGWB) monitors groundwater levels in the country and found that in 2021 more than 33% of monitored wells showed a drop of 0 to 2 meters, and some areas of major cities like Delhi, Chennai and Lucknow had seen a drop. more than 4 meters compared to the 2010-2019 average. (ALSO READ: India Suffers Worst Water Crisis In Its History: NITI Aayog)
The solution offered by the Indian startup can specifically help the beverage industry, which often has to deal with backlash from locals over concerns about depleting underground aquifers due to excessive water extraction. (For context: Coca-Cola factory permit revoked in TN after farmer protest)
We need more such initiatives and technological advances in our fight against the climate crisis.
