The potential for brackish water use in thermoelectric power generation in the American southwest

Threatened by a changing climate and the increased frequency of droughts and heat waves, more attention is being given to the sourcing of water resources. Especially in the American southwest, the frequency and severity of water shortages as well as elevated surface water temperatures has resulted in a series of threatened or imposed curtailments of thermoelectric power, the largest withdrawer of water in the United States. These cuts in generation can have important implications for the reliability and dispatchability of electric power, especially in summer months when electricity is needed most. This paper examines the potential for using brackish groundwater as a supplemental water source for thermoelectric power generation in seventeen western states and finds that the conversion of drought prone facilities to brackish backup systems would cost on the order of 60-70 thousand dollars per installed megawatt. Action from the federal government to foster basic research and technology readiness combined with state level action to require water resource contingency planning would encourage deployment of brackish water backup systems that would subsequently ensure resiliency and reliability of thermal generation during heat waves and in times of drought.