Concentrating Solar Power and Water Issues in the U.S. Southwest

Concentrating solar power (CSP) systems utilize the sun's energy to create heat that is used to generate electrical power. CSP systems in the United States are installed primarily in the Southwest, with 92% of plants that are operational, under construction, or under development located in three western states--Arizona, California, and Nevada. This report provides an overview of CSP developmentin these states, or the 'Southwest' for the purposes of this discussion, with a particular focus on the water supply issues associated with CSP. The Western Governors' Association (WGA) commissioned staff from the Western States Water Council (WSWC) to collaborate with staff from the National Renewable Energy Laboratory (NREL) to prepare this report. The WGA has long supported the effectivemanagement of the West's water resources, as well as the development of a clean, diverse, reliable, and affordable energy supply consisting of traditional and renewable energy resources. This report is specifically intended to help inform these goals, especially as WGA continues to underwrite a Regional Transmission Expansion Planning project, undertaken by the WSWC and the Western ElectricityCoordinating Council (WECC), to better understand energy development within the existing and future water resource constraints of the West. This report builds upon earlier research conducted by NREL, the University of Colorado-Boulder, and Stanford University that was supported through the Joint Institute for Strategic Energy Analysis (JISEA) and presents information gathered through extensiveresearch and literature reviews, as well as interviews and outreach with state water administrators and energy regulators, WECC and other experts familiar with CSP development in the Southwest.