U.S. Electrical Generation Water Demands: Modeling Scenarios for the Water-Energy Nexus
Generating electrical power is water-intensive because of water’s central role in thermoelectric cooling. Approximately 41% of the total U.S. freshwater supply is used by the electricity sector. A team led by scientists at Pacific Northwest National Laboratory used a multiscale version of the Global Change Assessment Model (GCAM) to evaluate interdependencies between electricity and water systems at the state level within the United States. Incorporating details at finer scales, GCAM-USA was used to simulate future electricity generation and associated water withdrawals and consumption using various scenarios. The team found: 1) lower withdrawals and higher consumption resulting from the conversion to closed-loop (from open-loop) cooling systems, 2) different energy-sector water demand behaviors with alternative pathways to the mitigation goal, 3) open trading of electricity benefiting energy-scarce yet demand-intensive states, 4) state homogeneity under certain driving forces (e.g., climate mitigation and water-saving technologies) but mixed effects under other drivers (e.g., electricity trade), and 5) a clear trade-off between water consumption and withdrawal for the U.S. electricity sector. With respect to electricity sector climate mitigation strategies, the team also noted that efforts centered on renewable energy and water-saving technologies exhibited a smaller water-demand footprint than those focused around nuclear power and carbon capture and sequestration. The study advances existing research by incorporating new technological and geographical details while exploring technological transitions. This research was funded by the Department of Energy’s Integrated Assessment Research Program.
Liu, L., M. Hejazi, P. Patel, P. Kyle, E. Davies, Y. Zhou, L. Clarke, and J. Edmonds. 2014. “Water Demands for Electricity Generation in the U.S.: Modeling Different Scenarios for the Water–Energy Nexus,” Technological Forecasting and Social Change, DOI: 10.1016/j.techfore.2014.11.004.