Imagine getting around 100 litres of water every day from thin air when Bengaluru is battling a water crisis. Thanks to a technology called atmospheric water generation, several institutions in Bengaluru, including government schools and hospitals, have regular water supply source on their premises.
The Atmospheric Water Generator (AWG) uses cutting edge technology under which water vapour in the air is converted into fresh and clean drinking water, which is 100% microbe-free. The vapour is converted to water droplets through the process of condensation. The water then goes through multiple filtration processes and is also passed through a mineral cartridge to infuse necessary minerals.
K. R. Puram Government Hospital was among the initial beneficiaries of this technology with the installation of two AWGs almost four years ago. With an installed capacity of 300 litres, the water from these generators is used for the dialysis centre and maternity division in the hospital in east Bengaluru.
“As we also have an RO plant, we do not use all of 300 litres every day, but we make use of 50 – 100 litres for drinking purposes. We get both hot and cold water. The generator keeps filling up as we draw water from it. However, if the air supply to the AWGs was better (currently, it is obstructed by a tree and glass casing around one AWG), then the water generation would have been much better,” said Praveena, in-charge nursing superintendent at the hospital.
Recently, an AWG of 250-litre capacity was installed at Government Higher Primary School, Rajarajeshwari Nagar. Kashinath Prabhu, the district director, CSR of Rotary District 3191, which implemented the project in collaboration with other institutions, said, “With this, we can provide at least half a litre of drinking water to each of the 300 children who come there. We are currently able to harvest 80% yield every day.”
Yield reduces in summer
While the yield from AWGs is usually higher in the rainy and winter seasons, the absence of humidity in the air during summer reduces the yield at some installations. According to sources, the yield from the AWG at Jawaharlal Nehru Planetarium has been around 50-60% of the installed capacity this summer.
“We do not see much generation during the day. But it happens during evenings and nights in summer. It has certainly proven to be helpful for drinking water purposes at the planetarium,” according to a source.
Maithri Aquatech is the technology partner for these installations, under their project Meghdoot. Including the aforementioned, they have a total of 21 installations in and around Bengaluru with capacity ranging from 40 litres to 5,000 litres. The installations are in residential buildings, corporate companies, educational institutions and the latest, the College of Horticulture in Kolar.
Cost concerns
According to S. Sridhar, director of a non-profit organisation Applying Technology For Social Changes (ATFSC) who has partnered with Maithri Aquatech to provide potable water to communities, there is an increased interest in the technology in light of the recent water crisis in Bengaluru.
“However, people are hesitant about installation due to power costs. The AWG consumes 0.25 units per litre. Overall, the cost comes up to ₹2 per litre, and maintenance is minimal. Just like RO systems, there are two filters inside, which should be cleaned once a year,” Mr. Sridhar said.