Water-energy nexus
The water-energy nexus is the relationship between the water used for energy production, including both electricity and sources of fuel such as oil and natural gas, and the energy consumed to extract, purify, deliver, heat/cool, treat and dispose of water (and wastewater) sometimes referred to as the energy intensity (EI). Energy is needed in every stage of the water cycle from producing, moving, treating and heating water to collecting and treating wastewater.