Superhydrophobic coatings for enhanced fog harvesting in arid coastal regions

Large areas across the United States and around the world are afflicted by drought, a condition that inflicts damage to local economies and particularly to agriculture. While some communities are turning to expensive energy-intensive processes such as desalination and long distance transport to address water shortages, NBD Nanotechnologies, Inc. is working to reduce stress on watershed resources by tapping into an underutilized fresh water resource - fog. Approximately 0.04% of the earth & #39;s fresh water is in the form of fog. In areas where fog droplets are heavy and the fog is thick, it can be collected by means of fog nets - simple systems with both minimal technology requirements and capital expenses. Fog harvesting has been so effective in some locations, that some developing communities are able to depend solely on fog nets to supply water for agriculture, cooking, and washing. Positive economic effects due to fog harvesting have already been observed in local populations along the arid coastal regions of Chile, Peru, and Nepal, among others. To date, fog nets are effective for harvesting water only in coastal regions where wind speeds are sufficiently high to support large fog droplets. In areas where fog is abundant but the size of the droplets is smaller, such as along the west coast of California, conventional polypropylene fog nets do not efficiently collect water. NBD Nanotechnologies, Inc. aims to optimize the surface chemistry and geometrical properties of the fog nets in order to harvest fog droplets too small for conventional netting. If successful, the technology would allow water to be harvested along the arid coastal regions of California, among others, to be used on site for irrigation or transported to drier regions. The proposed technology has already been proven by academic partners at laboratory scale. During Phase I of this project, NBD Nanotechnologies, Inc. will improve the chemistry of the coatings and scale up the manufacturing of the fog net prototypes. These prototypes will be tested under actual operating conditions in outdoor environments. Furthermore, NBD Nanotechnologies, Inc. will test the quality of the water collected as well as investigate the durability and wear performance of the coated fog nets over time and under accelerated wear conditions. If successful, Phase II of this project will focus on further scale up and marketing issues. The initial target market for the advanced fog net coatings will be vineyard businesses where a commercial size fog net would be capable of continuously irrigating six vine plants in full foliage. Through this work, NBD Nanotechnologies, Inc. hopes to create a profitable business, provide an inexpensive technology to harvest fog water, reduce the stress on existing watershed resources, increase job opportunities in the clean technology sector, and raise awareness of fog as a potential water source, particularly in California.