Integrated Energy-Water Planning in the Western and Texas Interconnections

Abstract

While long-term regional electricity transmission planning has traditionally focused on cost, infrastructure utilization, environmental impact, and reliability, the availability of water is an emerging issue. Toward this growing need, thermoelectric expansion should consider competing demands from other water use sectors balanced with fresh and non-traditional water supplies subject to climate variability. To address this need the Department of Energy's Office of Electricity Delivery and Energy Reliability supported an integrated planning project with funding through the American Reinvestment and Recovery Act (2009). Specifically, an integrated energywater analysis was performed to support transmission system planners in the Western and Texas Interconnections to explore the potential implications of water availability and cost for long-term transmission planning. The project brought together electric transmission planners (e.g., Western Electricity Coordinating Council (WECC) and the Electric Reliability Council of Texas (ERCOT)) with western water planners 1 (e.g., Western Governors' Association and the Western States Water Council). Efforts were organized into ten specific tasks: (1) project coordination and outreach; (2) thermoelectric water use; (3) non-thermoelectric water use; (4) water availability; (5) water cost; (6) environmental risk; (7) climate variability; (8) energy for water; (9) decision support system interface; and, (10) transmission planning support. Major accomplishments associated with this effort include: For the first time water availability was used to inform generation expansion planning by WECC and ERCOT (Section 11.2 and 11.3).  For the first time, projections of intensifying drought and its effect on reservoir levels, and thermal effluent discharge permitting were used to inform operational and expansion planning by ERCOT (Section 11.3).  Water withdrawal and consumption were characterized for each power plant in the WECC and ERCOT service areas/regions (Section 3.2). Water use factors were also developed for a range of unit processes that allowed projection of future water demands related to electric generation expansion planning (Section 3.

Data Challenges and Solutions in Energy‐for‐Water: Experience From Two Recent Studies

“…Understanding, managing, and optimizing energy use are therefore significant concerns for utilities. However, both practitioners and researchers seeking to advance sustainability continue to struggle to acquire even basic data on this subject (Sowby , , Sowby & Burian , Healy et al , Tidwell et al , Young , DOE , GEI Consultants Inc. , National Academies , ISAWWA , Bazilian et al , GAO 2011, Stillwell et al , Goldstein et al , Pate et al ). Because of local differences in treatment and pumping requirements, energy‐for‐water intensities vary widely across communities, and because there is often little correlation even to systems in close geographic proximity, it is critical to use specific, empirical data where possible.…”