Regional and temporal variability in water use intensity for thermoelectric power plants in the contiguous United States

Water is crucial for power generation and understanding how much water is needed in the process becomes the key when ensuring water and energy security. Water use intensity has been estimated in the United States based on reported water use and electricity generation data. However, the water use intensity has been often estimated using a single year of records without comprehensive consideration of regional and seasonal variations. This study is thus focused on quantifying the water withdrawal intensity (WWI) and water consumption intensity (WCI), considering the power plant characteristics as well as regional and seasonal variations. The spatiotemporal variations are evaluated using the public records provided by the Energy Information Administration (EIA) of 234 thermoelectric facilities in the contiguous United States (CONUS) for the period 2010 to 2019. The median and range of WWI and WCI for CONUS are estimated for 26 cooling-engine combinations, which is valuable for assessing water security and energy security. The results demonstrate that WCI for power plants using cooling systems with cooling ponds is more variable regionally. The seasonal impact is more significant for recirculating cooling with natural draft systems. The median WCI for CONUS is 1.22 L/kWh. The results also confirm that facility, regional and seasonal factors are important and should be considered when estimating the water use by thermoelectric power plants.