The human link
Rising senior Maria Tou served as the human link between MIT and Pontificia Universidad Católica (PUC) labs developing fog-harvesting technology in Chile. Fog collectors with standard woven plastic meshes have been used for decades in the arid regions of northern Chile to provide clean water to local communities. At MIT Professors Gareth McKinley and Robert Cohen developed new steel meshes with optimized geometry and superhydrophobic surface properties to improve the efficiency of these fog collectors. With the help of a MISTI Global Seed Fund grant, McKinley and Cohen connected with professors at PUC where the meshes can be tested on-site. Maria spent her summer working with this technology in two different fog-harvesting communities in Chile.
Fog harvesting abroad
Maria worked in the Mechanical Engineering Department at PUC where her first task was to design a wind-resistant camera fixture to enable in-field video of the meshes with a USB microscope. She made two trips to a fog-harvesting community in Peña Blanca (several hours north of Santiago) to implement the design and gain insight as to how fog droplets are caught, grow and drained on the installed meshes. This was an excellent opportunity for Maria to personally meet the people benefiting from fog harvesting technology and to experience how small, self-reliant communities live day-to-day.
In addition to building an understanding of fog interaction with the installed mesh, Maria also worked to better characterize the mesh itself. She started the process of developing a standard method to measure the “shade coefficient” property of meshes using image analysis in MATLAB.
Challenges of many kinds
It was a summer full of challenges for Maria: technical communication in a foreign language, unexpected project hurdles and collaboration with professionals across disciplines. These conditions forced Maria to confront engineering challenges she’d never face in the lab such as gusty winds that broke fog collectors and flying grit that made them too dirty to use. She found speaking a foreign language actually improved her scientific thinking: “It makes you slow down and think harder, especially in a technical setting,” Maria says. “It seemed that the Chileans focused on understanding science in order to solve a problem while at MIT the focus is on answering interesting scientific questions and then seeing how this knowledge could be applied.”
Maria returned to Chile over IAP in 2014 as part of MISTI 2.0, a program that expands the experience of students with previous MISTI experience. She helped begin a paper on methodology that is still being developed. “It’s a feeling of great satisfaction to see how my work helps a community and enables sustainability. I would want to work on another such project again using science and technology to help people and preserve the environment.”