The Impact of Rainwater Harvesting System Location on Their Financial Efficiency: A Case Study in Poland

Abstract

Natural water resources of Poland are among the lowest in Europe. In addition, the intensive development of urbanized areas and the associated increase in water demand necessitate the need to look for alternative sources. However, lim- iting the amount of resources available for use does not go hand in hand with the development of ecological awareness of society, which has the greatest attention still attached to the financial criterion. Considering this, the studies have been conducted to determine the cost-effectiveness of the rainwater harvesting system (RWHS) in a single-family house located in selected Polish cities where rainfall varies in height. Financial analysis for four different variants ofthewater supply system in the building in question has been done using the Life Cycle Cost (LCC) Methodology. The results show that RWHS financial performance varies widely, but it has also been found that the variant in which rainwater will be used to flush toilets, wash, andwater the garden is characterized by the lowest LCC costs irrespective of tank capacity, number of users, and the location of RWHS system. The study also examines the impact of the capacity of the rainwater storage tank on the tap water savings. Depending on the installation variant these savings ranged from 11– 40% for Zakopane, 10–25% for Warsaw and Katowice, and 10–28% for Koszalin