Thermodynamic assessment of the recovery of air conditioning condensates as a sustainable water resource in arid regions

The lack of water in today’s world can be considered one of the major issues that we are experiencing. In most countries, with special emphasis on the Arab and Gulf regions, large quantities of water are wasted annually in the form of condensates which result from air conditioners and are then immediately end up in sewage systems rather than getting reused and recycled. The current study’s aim is to investigate the possibility of alleviating the issue of water scarcity in arid environments by recovering air conditioning condensate. A thermodynamic model was formulated, verified and simulated using the Engineering Equation Solver (EES) software, showing the condensation process of water in air conditioner systems, which was then used to predict the quantity of condensate produced under real weather conditions. The results indicated that in Saudi Arabia, nearly 372 million m 3 of condensate water were generated throughout summer months (June-October). Harnessing this resource could supplement existing water supplies while achieving a net energy saving of approximately 0.5–1.4 TWh and avoiding between 350,000 and 980,000 tons of CO 2 emissions per year compared to conventional fossil fuel-based desalination.