Witnessing the lack of drinking water during a field trip in the mountainous region, two fourth-year students from Hanoi University of Science and Technology came up with the idea of generating water from air.
At the end of 2019, Dang Pham Phu Linh and his classmates from the Mechatronics Department, Institute of Mechanical Engineering, Hanoi University of Science and Technology participated in a field trip to Son La. The three days spent there were challenging for Linh and the group due to the scarcity of drinking water. Observing the difficulty of accessing water in remote mountainous areas, Linh returned to school determined to find a solution to this problem.
After sharing the idea with his classmate Lai Anh Quan and receiving suggestions from their teacher, the two students sought to create a machine that generates water from air.
The machine was designed based on a simple principle, similar to pouring cold water into a glass and placing it in a room at normal temperature, where droplets of water appear on the outside of the glass after a while. “This phenomenon occurs because the water vapor (which makes up 70%) in the air condenses, not because the water in the glass evaporates,” Linh explained.
Utilizing the condensation phenomenon, Linh and Quan began to implement their idea in early 2020. The group used a thermoelectric module (a semiconductor device with one cold side and one hot side) for direct heat dissipation, but the rapid heating caused the cold side of the module to be unable to keep up, resulting in no water being collected. The group faced failure.
During this time, due to the inability to find a solution and a packed class schedule, the group had to temporarily halt their work on the machine. It wasn’t until April of this year, upon hearing about the environmental protection solution competition, that Linh and Quan returned to continue refining the machine to participate.
Structure of the water-generating machine from air. (Photo: Research Team)
Learning from their previous failure, instead of using the thermoelectric module, this time Linh and Quan employed separate hot and cold units to enhance heat dissipation speed, allowing for more condensation of water vapor. Specifically, air passes through a filter and is drawn into the cold unit at a temperature of 2-10 degrees Celsius. Thanks to the hot unit, the water vapor passing through the cold unit condenses into droplets and flows into a collection box.
The cold unit was repurposed from an old air conditioning unit and placed below the hot unit for heat dissipation. Additionally, a RO filter core was attached at the air intake and water output to remove dust, bacteria, and a mineralization core (containing mineral stones, pink pebbles, and marble) to create a natural sweetness.
After two months, the team completed the product with a total cost of 4 million VND. Testing under environmental conditions of 25-35 degrees Celsius and humidity above 60%, the machine collected 1.5 liters of water per hour. After one day, nearly 30 liters were collected, enough for a household of 4-5 people for daily use.
Linh mentioned that when given to some people for tasting, most remarked that the water had a light sweet taste and was easy to drink. However, in the near future, the group plans to send samples to a testing lab to evaluate and determine the specific components and properties of this water.
Participating in the Vietnam Youth Action for Climate competition, Linh and Quan’s product made it to the top 10. To optimize the product for practical use, the team plans to add a sensor that alerts users when to replace the filter and a UV light to ensure the elimination of harmful bacteria in the water.
