Water and energy management in a sustainable site: A case study of a living environment for street children in Tehran, Iran

Urban development of major cities in Iran, especially in metropolises like Tehran, triggered an ever-increasing water and energy demand leading to water crisis deterioration and electricity generation deficiency. Building energy demand is either provided by fossil fuels or fossil-fuel-generated electricity in Iran, so the energy resources are mainly non-renewable. The current study addressed such an unbalanced pattern by proposing an applicable cross-disciplinary methodology for a sustainable urban design. A case study was conducted in a site located in northern Tehran, and multiple sustainable design alternatives were examined. Water, electricity, and energy demands were compared between a conventional design and a sustainable one. Water and energy management scenarios were defined, encompassing rainwater harvesting, greywater recycling, efficient landscape plantation and irrigation, water treatment, reducing construction materials? heat transfer, and photovoltaic electricity generation on site. Evaluations showed promising results indicating: 69.73 % less water demand from city water supply; 68.60 % less electricity demand from national grid; 43 % reduction in cooling and 56 % reduction in heating loads. The decentralized water management system reduced the risk of over flooding in the city wastewater network. Furthermore, a shift to renewable energy resources was achieved, and fossil fuel consumption consequences were alleviated by applying a grid-connected photovoltaic system.