Water-Energy Nexus of Brackish Water Desalination for Mitigating Water Scarcity Region: Challenges, Performance, and Potential Solutions

Water scarcity represents one of the greatest challenges facing the Hashemite Kingdom of Jordan. Jordan is the second water-scarce country in the world, with only 100 m3 per capita, which is less than the minimum estimated limit for safe water supply (500 m3 per capita) by about five times. Thus, the water deficit in Jordan is alarming. It is projected to increase with the rapid progression in water demands associated with the unsustainable population and economic growth patterns. In the water-energy nexus (WEF-Nexus), the water challenges are associated with issues related to securing energy sources since the country imports about 97% of its energy supply. The pressure created in the water sector led to higher electricity tariffs, which negatively impacted the agricultural, domestic, and primarily industrial sectors. The high energy costs are hindering the industrial growth in Jordan. This study confirms that increasing water demands have imposed the exploitation of most groundwater sources in Jordan and deteriorated its quality, specifically by increasing salinization. Additionally, in the context of food-water-energy nexus, poor brine management, especially in the agricultural sector, has been identified as one of the primary causes of soil damage due to high salt concentrations, which is inducing the rate of desertification, leading to a drastic decline in the farming capacity in Jordan. The potential of brackish water reverse osmosis desalination to combat the water deficit in Jordan was assessed in this study in the context of the water-energy nexus. Interviews and surveyed questioners were employed to multiple stakeholders from different sectors in Jordan, including the agricultural, domestic, and industrial sectors. Challenges were faced in data collection as the brackish water reverse osmosis desalination technology is considered somehow new in Jordan.

Three brackish water desalination plants were assessed from the agricultural, domestic, and industrial sectors. The study shows that the capacity of medium-scale brackish water desalination plants powered by the electricity network was in the range of 460-1240 m3/day. They had a specific energy consumption of 2.7-5.6 kWh/m3, and the desalination cost was about 0.62-1.18 USD/m3. In comparison, the larger brackish water desalination plants had a 12,600-32,400 m3/day capacity. Their average specific energy consumption was about 3 kWh/m3, and approximately the desalination cost was 0.65 USD/m3. It was concluded that the larger the plant’s capacity, the less water production costs become. The brackish water desalination plants in the industrial sector were associated with the highest economic and energy consumption. In general, there is a need to improve the water and energy performance of the assessed brackish water desalination plants in Jordan. This reduces the pressure created by the over-pumping of groundwater sources and the associated operating costs. Jordan is blessed with an abundance of solar energy, so photovoltaic (PV) solar panels have been suggested to reduce the energy consumption patterns for the assessed brackish water reverse osmosis plants to get closer to our energy benchmark of 1.3 kWh/m3. In this study, the installation of PV panels showed about 50-54% energy and cost reduction in the lifetime period estimated as 15 years for the brackish water desalination plants in the industrial sector and 20 years for those in the agricultural and domestic sectors. The study showed promising results for the potential cost-effectiveness of brackish water reverse osmosis desalination powered by PV panels (PV-BWRO desalination).