WATmosfAIR

Approximately one of three persons worldwide either lacks access to clean drinking water or must coover extremely long distances to obtain it. Remote regions with arid climates are particularly affected by drinking water shortages. This means a social disadvantage especially for girls and women, as they are typically responsible for fetching water and therefore have no or less time for education and training.

The water content of the air in the entire atmosphere is 13,000 cubic meters. Although only the ground-proximate layers of air are can be used, this offers significant potential for drinking water production, as this source is accessible everywhere.

In order to condense the gaseous water in the air, the temperature must fall below the dew point line. This is achieved either by cooling the air temperature down to the corresponding dew point or by increasing the dew point temperature.

The air is conventionally cooled using electrically powered compression chillers. Numerous commercially available devices already exist for this purpose. In areas with high humidity, this is a very sensible approach. However, the situation is different in arid regions with low atmospheric moisture. By definition, air with a dew point of 5 °C or lower is classified as arid; the dew point is often even below the freezing point of water. The direct condensation of water from the ambient air using electrically powered compression chillers is therefore not suitable for drinking water production in arid climates.

In previous IGTE projects, a solar-sorptive process for extraction drinking water from air was developed, and a demonstrator was built and tested on the campus of the University of Stuttgart. The proof of concept has already been demonstrated under the climatic conditions of Stuttgart.

The main objective of the project is a development strategy to the concept of solar-sorptive drinking water production from air - starting with a site in Cameroon - to the relevant areas, considering technical, economic and social aspects. On the one hand, this requires further technical development (making the system more compact, efficient, cost-effective, and fully self-sufficient). The system will therefore be adapted and further developed, taking into account the location-specific conditions of a site to be selected in Cameroon. On the other hand, an essential component of the development strategy is to establish an international network and knowledge transfer in order to be able to transfer the concept to other regions and countries of the world considering individual boundary conditions.

The feasibility of both the technical and social aspects will be evaluated and, if possible, realized at a site in Cameroon, to be selected together with the partners. From this site, the network members will then examine the transferability of the results and experiences to other areas with similar climates and social forms and develop a development strategy.

The site will be developed in close cooperation with scientists and students from the University of Maroua, they will be closely involved.

The on-site demonstrator is intended to serve as a flagship project and inspire further research.

To ensure a lasting impact beyond the research project's duration, one or more competence centers will be established to provide general knowledge and raise awareness of the connection between clean drinking water and sanitary facilities as well as health and quality of life. These centers will help counteract social disadvantages - especially for girls and women - through education and outreach.

Additionally, the technical and physical principles of the concept, as well as the functioning of the solar-sorptive water production system, will be explained and communicated.

01/01/2025 – 12/31/2026

Deutsche Bundesstiftung Umwelt (German Federal Environmental Foundation)

Reference Number: 39865/01-24/2

• HydroTec Gesellschaft für ökologische Verfahrenstechnik mbH
• MB-P Consulting