A study to assess alternative water sources for reducing energy consumption in a medical facility case study, Abu Dhabi

Abstract

This paper presents the case for water and energy conservation in a desert type climate healthcare environment, which is based on the need for Abu Dhabi to decrease potable water and energy consumption to reduce environmental impact. The work documented in this paper is part of the first author’s Professional Doctorate change project in Sustainable Built Environment (D.SBE) at Cardiff Metropolitan University with a medical facility case study in the United Arab Emirates (UAE) in use since 2015. The project is investigating the impact of alternative water sources energy consumption versus public network seawater desalinated potable water for outdoor use. The context is a 364 beds hospital in Abu Dhabi with a 21,600m² building footprint area surrounded by a 36,310m² vegetated open space. The hospital includes a treated air cooling condensate water system suitable for use as irrigation water and water feature use. The condensate water has been tested in 2016 and 2017 to verify compliance for reuse. Whilst, the water test results demonstrate suitability for outdoor reuse in a healthcare setting, additional alternative water sources such as fire test pump water (450m³/year) have been tested in March 2017, which shows that a tertiary treatment system is needed for its reuse. It was also found that onsite alternative water sources are less energy intensive for irrigation (0.22kWh/m³) and water feature use (39.09kWh/m³) than offsite produced desalinated potable water (55.68kWh/m³ average). The next steps are to quantify the treated condensate water from the air cooling system for 12 months through the newly installed flow meters at the raw condensate water tanks to confirm the 2013 theoretical model and calculate yearly water energy consumption. To date (March 2017) 26 days of data have been recorded (February to March 2017) which align with the model by data extrapolation. This study will help understand how alternative water sources for outdoor use, impact on building systems energy consumption, greenhouse gas emission, operation and maintenance cost and the environment. This study may be beneficial to local competent authorities for making and adjusting standards for energy and water conservation strategies in healthcare settings.