Google ‘atmospheric water generators’, or AWG, and you get a range of sites that sell them. Chennai-based start-up VayuJal Technologies has produced four of these AWGs — three of 100 litres a day capacity, and one of 400 litres — on a pilot basis. All four are being used to generate re-mineralised water that can be consumed and used for cooking .

The concept of tapping humid ambient air to produce potable water may not be new, but in the context of the severe water shortage in Chennai and some other parts of the country, this may be a viable option.

VayuJal’s 400-litre unit has been installed at a guest house in IIT-Madras, and the water produced is used in the kitchen and bottled for guests.

According to Ramesh Kumar Soni, Director and CEO of VayuJal, water produced by these AWGs costs ₹1.80 to ₹2 a litre right now. There have been requests from apartment dwellers for AWGs of smaller capacity, say, 30 litres a day. The company is also working on a 2,000-litre unit, which will be ideal for small restaurants.

Pricing issues

But before AWGs can go mainstream, their prices have to come down. Experts say this will happen with more research on the materials used and higher sales volumes.

The 100-litre unit will cost ₹1.5-1.6 lakh and the 400-litre unit, ₹5.5 lakh, says Soni, adding that VayuJal is working on reducing the prices. He reckons that a 30-litre unit will cost ₹50,000-60,000, but the aim is to match the best RO unit, at ₹25,000-30,000.

At the Aero Show in Bengaluru in February, BEL launched an AWG that the defence PSU is making in collaboration with CSIR-IICT and Maithri Aquatech Pvt Ltd, a Hyderabad-based start-up.

These water generators can now work only in humid areas, but research is on to make them work in a desert State such as Rajasthan, as well.