WATER + STORMWATER
A typical 600-megawatt power plant, Varanasi said, could capture 150 million gallons of water a year, representing a value of millions of dollars. This represents about 20 to 30 percent of the water lost from cooling towers. With further refinements, the system may be able to capture even more of the output, he said. What’s more, since power plants are already in place along many arid coastlines, and many of them are cooled with seawater, this provides a very simple way to provide water desalination services at a tiny frac- tion of the cost of building a standalone desalination plant. Damak and Varanasi estimate that the installation cost of such a conversion would be about one-third that of building a new desalination plant, and its operating costs would be about 1/50. The payback time for installing such a system would be about two years, Varanasi said, and it would have essentially no environmental footprint, adding nothing to that of the original plant. “This can be a great solution to address the global water crisis,” Vara- nasi said. “It could offset the need for about 70 percent of new desali- nation plant installations in the next decade.” In a series of dramatic proof-of-concept experiments, Damak, Khalil, and Varanasi demonstrated the concept by building a small lab ver- sion of a stack emitting a plume of water droplets, similar to those
seen on actual power plant cooling towers, and placed their ion beam and mesh screen on it. In video of the experiment (https://youtu. be/3u6ZNSaRhfg), a thick plume of fog droplets is seen rising from the device — and almost instantly disappears as soon as the system is switched on. The team is currently building a full-scale test version of their system to be placed on the cooling tower of MIT’s Central Utility Plant, a natural-gas cogeneration power plant that provides most of the cam- pus’ electricity, heating, and cooling. The setup is expected to be in place by the end of the summer and will undergo testing in the fall. The tests will include trying different variations of the mesh and its supporting structure, Damak said. That should provide the needed evidence to enable power plant opera- tors, who tend to be conservative in their technology choices, to adopt the system. Because power plants have decades-long operating life- times, their operators tend to “be very risk-averse” and want to know “has this been done somewhere else?” Varanasi said. The campus power plant tests will not only “de-risk” the technology, but will also help the MIT campus improve its water footprint, he said.
Information provided by MIT (www.mit.edu).
clean water for those who do not have access to it is one of its global outreach goals. One of the organizations the church partners with is Living Water In- ternational (LWI; https://water.cc/aboutlivingwater). LWI is based in Houston and operates in South American countries, the Dominican Re- public and Haiti, and parts of Africa. It exists to help communities gain access to clean water, and through that experience share the gospel. Our team of 11 people varied in age, gender, and professional experi- ence. We flew into the capital, Guatemala City, and drove to Antigua, where LWI’s Guatemala operations are based. Antigua is a beautiful city, rich with history, architecture, and infrastructure. The streets are rough, uneven cobblestone and the city center has many buildings that were once used by the government when Antigua was Guatemala’s capital. Some churches and buildings we toured dated as far back as 1546. While this was an amazing cultural experience, it was in complete contrast to what we experienced as we made the trip the following day to the village where the drill site was located. The community where the well would be installed was a small village of 650 people between the cities of Masagua and Escuintla. Further along our route to the drill site, the level of poverty in the area became clearer. Most buildings and
Goodwill in Guatemala
Volunteers working with Living Water International help drill a well to provide clean water for a rural village. By Samuel LePore
September through February , much of South America experiences dryer, cooler weather. This means aquifers tend to be lower and the groundwater is lower near populated areas that draw water from those aquifers. This is amplified by the large amounts of water required for the region’s agricultural industry, specifically sugarcane, which I ob- served recently driving past a field at sunset in Masagua, Guatemala, with water jets shooting out over endless fields. In February, I traveled to Guatemala to take part in installation of a drinking water well for a small community with little access to clean water — or any water at all at times. The opportunity to be part of this project was first presented to me in summer 2017. The logistics of the trip and the team were put together by Parkview Community Church, the church I attend with my family in Glen Ellyn, Ill. This church leads mission work all over the world in a variety of capacities. Providing
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