Design and Development of an Integrated Water System Combining Rainwater Harvesting System (RHS) and Atmospheric Water Generator (AWG)
Zohra, Fatema Tuz
<p>The <i>objective</i> of this research is to design and develop a smart integrated water system that combines two off-grid freshwater resources- Rain Harvesting System (RHS) and Atmospheric Water Generator (AWG) to establish a potential solution to the <i>problem</i> of freshwater scarcity. A preliminary study and data analysis are carried out based on the local (San Marcos, TX) historical precipitation and atmospheric water generation data to figure out the suitability of the idea to integrate these two off-grid (independent from municipality water grid) water systems. A vertical farming unit in the Freeman Center, San Marcos, TX, is considered as a case study to implement and test this water system, and smart automation is introduced to meet the fitness of this farming unit. Later, water quality is tested to evaluate the fitness of this water to aid plant growth and good health. Finally, a suitable water storage tank capacity is determined for this integrated system based on the water demand pattern of two soilless farming units. This article explains the procedure, component modification, and construction strategy for data analysis, mechanical and electrical systems, network, and data logic design for the implementation of this integrated system. An experimental setup is established in the lab to test if the smart logic system for automation is working correctly with all the electrical components. Given the COVID-19 pandemic situation, fabrication/installation of related electrical and mechanical equipment onsite is not possible.</p> <p><i>Results</i> of the data analysis showed that RHS-AWG integrated system could provide stable and sustainable water. Introducing smart automation through real-time feedback from surrounding atmospheric conditions and automatic refill of nutrition supply tanks facilitates energy-saving and eliminates labor in this project. The water quality of this system resembles the purest water with an acceptable pH range and a combination of minimum salinity and minerals suitable for nutrition control for the growing plants. Based on the local (San Marcos, TX) rainfall data, it is found that RHS alone is enough to meet the required year-round water demand with a bigger storage tank capacity. Still, having AWG as a back-up in this integrated system ensures the availability and supply consistency for the months when there is almost no rainfall. This research is vital because integrating more than one off-grid water system with vertical farming units can be an all-in-one potential solution of the uprising freshwater and food scarcity problem. In remote areas, this can reduce the dependency on municipality water or other freshwater resources such as a river, wells, and underground water. Although this water system is specifically designed for a vertical farming unit, it is scalable and adjustable for any freshwater-related application. An integrated RHS-AWG-Municipal water system can be investigated to optimize cost and risk to make this system more applicable for public use. Radiofrequency and wireless technologies, cloud data collection, etc. can be used in the future for analyzing weather-related forecasting data to offer more compliant design of the water system.</p>
Automation with Arduino, Integrated water system, Atmospheric water generator, Rain harvesting system, Water quality
Zohra, F. T. (2020). <i>Design and development of an integrated water system combining Rainwater Harvesting System (RHS) and Atmospheric Water Generator (AWG)</i> (Unpublished thesis). Texas State University, San Marcos, Texas.