Abstract
Increasing competition for water resources in the United States could
create future challenges for allocating and using thermal cooling water
in the U.S. electric power sector. While thermal power plant retirements
and the growth of wind and solar technologies can reduce national
aggregate power sector cooling water use, local water constraints and
growing demand for agricultural or municipal supply could create greater
needs for higher-cost alternative water supplies such as groundwater or
recycled wastewater. For some regions, these incentives could change
future electricity planning and operational decisions. These
relationships and impacts are studied here using the National Renewable
Energy Laboratory (NREL) Regional Energy Deployment System (ReEDS), a
national electric sector planning model that has recently been upgraded
to include a highly detailed representation of thermal cooling water
demand and supply. Thermal power technologies are differentiated by both
cooling technology and water source type to track and constrain thermal
cooling water use in a way that incorporates both physical and legal
water considerations in the United States. This capability is exercised
under a range of electricity sector futures with alternative technology
costs, fuel prices, and water constraints to illustrate ways that U.S.
electric sector water use could evolve under uncertain future electric
sector drivers. In exploring changes to regional generation and
transmission planning and operation, water requirements, and cost, we
highlight the environmental and economic impacts of future power sector
water decisions.