Water and energy are resources that are linked, because generating energy requires water, often in large quantities, and energy is needed for pumping, treatment, and distribution of water and for collection, treatment, and discharge of wastewater. This interrelationship is often referred to as the energy-water nexus, or the water-energy nexus (WEN). The Foundry’s Jeff Urban details the challenges and opportunities in the WEN in a recent issue of Joule.
The interconnection between energy and water resources, along with recent trends in population growth and energy consumption, presents an urgent demand for innovation. Current research priorities in the water-energy nexus include water-free energy generation, CO2 sequestration, low-energy separations, and enhanced fluids, but there is plenty of space for further advancement.
Urban reviews the most pressing technological challenges related to WEN, and also discusses opportunities to make water and energy generation more efficient with respect to one another; from using nanostructured hydrophilic surfaces to improve heat transfer in cooling operations to developing new membranes to make desalination less energy intensive.
Urban also highlights one aspect of the WEN that is often overlooked: the science behind fouling and scaling as a part of our water cycle. Any membrane-based water filtration system has problems with the membrane becoming clogged over time, and is such a serious problem that water often must be pre-treated before the actual filtration process can occur. Impure water used in an industrial setting will cause scaling and buildup on the interior surfaces of a cooling system and reduce efficiency over time.