Rainwater harvesting system design for green building scope: Example of Yalova University Engineering Faculty

Water is the most significant and essential resource for the sustainability of life. Due to the increasing population and climate changes in recent years, humans are faced with the possibility of extinction of this indispensable resource. Turkey is being in the list of countries, currently suffering water shortages and in near future, it is estimated to be poor. Therefore, it is important to research water saving methods in order to protect and sustain water resources. Based on this understanding, in this thesis, rainwater harvesting system was discussed within the scope of the green building for Yalova University Faculty of Engineering. The harvested water is intended to be used in toilet reservoirs in the building. First of all, the statistical analysis of the precipitation regime was made. In order to find the optimum storage volume, regression analysis was performed and the results were evaluated. With the researches and calculations, it was determined that there are a minimum of 300 and a maximum of 1500 students in the building simultaneously, and the tank volume and efficiency were evaluated for water demands in this range. Two approaches were used for storage assembly. Economic analysis is made by considering different scenarios for multiple demands, not for a single water demand. The cost of the storage was calculated and the savings potential and payback periods were determined for the demands in the range of 3000-15000 liters. According to two approaches, the minimum payback period is 6 years and the maximum repayment period is 13 years.