mbeva
ABSTRACT
This project explores the development and implementation of a fog harvesting system designed to provide a sustainable source of water in arid and semi-arid regions. By capturing water droplets from fog using specialized mesh structures, the system offers an eco-friendly and low-cost solution to water scarcity. The study evaluates mesh efficiency, water collection rates, and environmental suitability. Results demonstrate that fog harvesting can supplement water supply in dry areas, supporting both domestic and agricultural needs.
STATEMENT OF THE PROBLEM
In arid and semi-arid regions, access to clean and reliable water sources remains a significant challenge due to low rainfall and limited groundwater. Traditional water sourcing methods like wells and boreholes are expensive and unsustainable. Therefore, there is a need for alternative methods such as fog harvesting that utilize naturally available atmospheric moisture.
HYPOTHESIS
If a fog harvesting system is deployed in arid areas, then it can collect a substantial amount of water to supplement domestic and agricultural water needs.
OBJECTIVES
- To design and construct a functional fog harvesting prototype using affordable and locally available materials.
- To evaluate the efficiency of different mesh materials in collecting water from fog.
- To measure the volume of water harvested under various weather conditions.
BACKGROUND INFORMATION
Fog harvesting is a passive and environmentally friendly method of collecting water from fog. This technique involves placing vertical mesh structures in fog-prone areas to capture tiny water droplets suspended in the air. These droplets condense on the mesh, flow down, and are collected in storage containers. The technology has been successfully implemented in countries like Chile, Peru, and Morocco, making it ideal for water-stressed regions that frequently experience fog. The method is simple, cost-effective, and requires minimal maintenance, making it suitable for rural and underserved communities.
MATERIALS
- Polypropylene mesh (shade net)
- Support poles (wood or metal)
- Collection trough/gutter
- Water storage tanks or containers
- PVC pipes or hoses
- Anchoring ropes and pegs
- Measuring cylinders or jugs
- Thermo-hygrometer (to measure humidity and temperature)
- Weather data records
METHODOLOGY
- Site Selection:
A fog-prone, elevated area within a semi-arid region was selected based on fog frequency and terrain. - Design and Setup:
A frame was constructed using metal poles to support a vertical polypropylene mesh of 1 m². A gutter system was fixed at the base of the mesh to channel collected water into a storage container through PVC pipes. - Water Collection:
The setup was monitored during early morning hours when fog formation is most frequent. Water collected in the container was measured daily using a calibrated cylinder. - Data Analysis:
The amount of water collected was recorded for several days. Data on temperature, humidity, and fog density were also noted. Mesh performance was analyzed based on average daily yield and environmental conditions.
RESULTS
The fog harvesting system collected an average of 2.5–5 liters of water per square meter of mesh per day. The collection rate varied with humidity and fog density. Polypropylene mesh showed high water retention and effective droplet capture. The collected water was clear and suitable for non-potable uses such as irrigation and cleaning after basic filtration.
DISCUSSION
The system performed efficiently under favorable weather conditions, especially in the early morning and during overcast days. Mesh material, wind direction, and site elevation greatly influenced the amount of water collected. Although the system doesn’t fully meet household water needs, it provides a reliable supplementary source. In scaling up, communities could install larger or multiple meshes to improve yield.
RECOMMENDATIONS
- Use durable and fine-mesh materials to improve water capture efficiency.
- Train local communities on construction and maintenance of fog harvesting systems.
- Combine fog harvesting with rainwater harvesting systems for improved reliability.
- Engage policy makers and NGOs to support adoption in water-scarce regions.
CONCLUSION
Fog harvesting presents a promising solution to water scarcity in arid and semi-arid regions. With proper site selection and community involvement, it can significantly enhance water accessibility using a cost-effective and environmentally sustainable approach.
