H2E
Improving access to safe drinking water by harvesting it directly from the air
H2E (“Hydration to Everyone)” was an early stage project that explored ways to improve access to safe drinking water. The team created a device which pulled water from the air and developed geospatial tools to map where these kinds of devices could meet people’s daily water needs. After wrapping up their investigation, the team shared its findings in the H2E Collection so that others in the field could build upon their work.
A Dearth Of Drinking Water
Access to clean drinking water remains a challenge for 2.2 billion people. Nearly 1 in 3 people worldwide don’t have reliable or affordable access to safe drinking water—a number that climate-change related events are expected to exacerbate. In some countries, families spend anywhere between 10-50% of their income just to secure water. Women and children often bear the added burden of spending hours collecting the water their families need.
Pulling Water from Thin Air
Around the world, there are a broad range of social, geographic and structural issues preventing people from accessing clean water. However, everyone has access to the air and the sun. The H2E team—a small group of scientists, development experts, engineers, geospatial analysts, user researchers and industrial designers—started with a question: “What if people had access to an affordable, easy-to-use, solar-powered device that harvests daily drinking water from the air?"
Atmospheric water harvesters (AWH) — devices that pull water from the air — have often been overlooked as a potential solution due to their relatively low outputs compared to technologies like desalination, but they have unique advantages. While it’s improbable that AWH could singularly solve the problem, their small, modular design and renewable power could potentially fill a critical gap in areas where safely managed drinking water infrastructure falls short.
An Affordable, Sustainable, Off-Grid Device
The team investigated whether AWH could work in regions with low access to safe drinking water. Their research, published in Nature, was the first global study to prove that these devices could help 1 billion people worldwide.
With this potential in mind, the H2E team set out to build a low-cost, sustainably-powered device that could provide a person’s daily water needs. They aimed to build a device accessible to people living on $2 to $8 a day, that functions in dry climates, and capable of producing water at a cost target of $.01 a litre.
Warm Air Meets Cooler Air, Condensing Into Liquid Water
Sunlight is used to heat a recirculating stream of air inside the device’s solar heater.
With help from a dessicant (an absorbent material), the hot, recirculating stream of air absorbs moisture from ambient air being drawn from outside the device.
The warm, humid stream of air passes a cooler stream of air in the heat exchanger, where it cools down.
Liquid water collects at the bottom of the device. Remaining, cool air travels back up through the device to be reheated in the heat exchanger, and the cycle continues.
H2E Today
After numerous iterations, the team successfully built a low cost, solar-powered prototype that produced enough water to meet a person’s daily water needs for ~$.10 per liter. To produce water at the team’s target of $.01 per liter was going to require significant hardware integration and mass production expertise, which is not X’s sweet spot.
During the course of the project, the field of atmospheric water harvesting was evolving — with new research groups, startups, and NGOs — springing up to work on ways to harvest drinking water from the air.
Given these factors, it became clear that X commercializing the technology wasn’t the right decision. Instead, sharing the team’s learnings with others tackling this challenge would be the best way to make an impact. . Even at ~$.10 per liter, the device could have a positive impact in many communities. In 2021, the H2E team made its datasets, geospatial analysis tools, prototype designs, and hardware documentation publicly available in The H2E Collection, ensuring that others could continue the work. By making the research public, the team hoped to accelerate progress toward a future where everyone has access to safe drinking water.
