Watts in a Drop of Water: Savings at the Water-Energy Nexus

This paper shows a range of energy intensities for water and wastewater services and in residential hot and cold water. We draw from existing data to develop national estimates of energy savings associated with water savings, including energy used in water conveyance, water heating, and water and sewage treatment. We see that the range of energy intensity of water varies dramatically, particularly in the water service sector (source, conveyance, and treatment). This is largely due to differences in the size of water systems, pumping requirements between locations, and raw water characteristics. Further work in exploring the water-energy nexus will depend on increased end-use information, empirical data, and examples in the literature.