Fog harvest as water catchment technology
Fog has the potential to provide an alternative source of water in the dry regions and can be done with cheap technology. The water that is captured can be used for domestic use and irrigation. The technology works best in areas where there are great fogs, especially in the coastal regions. The technology captures the fog as it moves to the inland. You could also collect water in mountainous regions if there is water in cumulus clouds.
The fog-harvesting system consists of a double or a single layer mesh that is supported by two posts. The mesh is made of such material as nylon, polyethylene or polypropylene. The system should be positioned in a location that is perpendicular to the prevailing wind to collect water as the fog passes. The size of the meshes depends on the topography of the land, the amount of water needed and the budget.
The gravity is vital to the working of the system. The water droplets that collect on the mesh run down to a gutter at the bottom of the net and are channeled via pipes to a storage tank or cistern. A standard fog collector is capable of collecting about 200 liters to about 1000 liters a day. The efficiency of the system can be increased by using narrower collection fibers. The increase in fog droplets and higher wind speeds increase the amount of water collected.
Maintenance of the system
It is important to inspect the mesh nets and cable tensions. This prevents the structural damage of the systems and maintains the water harvesting efficiency. The nets, drains, and pipelines should be cleaned of dust, algae, and debris.
The storage tank should also be well-maintained to prevent contamination and accumulation of fungi and bacteria. If the spare parts are not easily available, the spare parts should be bought in advance reserved for any repair that may be needed in future.
The fog-collected water is devoid of many harmful microorganisms and can be used for both the irrigation and domestic use. The system has very little impact on the environment, and its installation is not labor intensive.
One the other side, the system may not be reliable given then fog in unreliable in some regions. The projected amount of water is sometimes hard to achieve given the uncertainty. Where the system works, it delivers lots of water with very little maintenance cost. It is a good alternative to conventional water supply systems that are sometimes expensive.
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