From Bureau of Economic Geology, The
University of Texas at Austin (www.beg.utexas.edu).
For more information, please contact the author.
Bureau Seminar, January 25, 2013
Link to streaming video: available 01.25.2013 at 8:55am
Dr. Bridget Scanlon, Robert Reedy, Ian Duncan, Nalun Fernando, Jon Paul Pierre, Alex Sun, and Michael Young
Bureau of Economic Geology
Jackson School of Geosciences
Univ. of Texas at Austin
Texas experienced the most extreme one year drought on record in 2011 with projections of 3000 MW of electricity shortages if drought extended another year. Lack of electricity storage results in the need to meet peak electricity demands during the hottest times (Aug 1 – 4, 2011) when water supplies are lowest (reservoir storage reduced to ~60% during drought), amplifying the water energy nexus problems. The objective of this study was to evaluate drought vulnerability of electricity generation in Texas. Water use for electricity generation was determined from federal (EIA) and state (TWDB and TCEQ) databases for 2010 and 2011. Most (86%) electricity generation required water for cooling, consuming 0.46 million acre feet (maf, 2011), and representing 3% of total water withdrawal in the state. Although ~19 maf is recirculated for cooling, 98% of this water is returned to the source. Drought vulnerability of electricity generation in Texas results from reliance mostly on surface water, with runoff reduced to < 1 percentile during 2011, reservoir storage for power plants decreasing to < 50% in a third of the monitored reservoirs, close to intake levels in only a couple of plants, and high temperature discharges in a few plants. Drought resilience can be increased by reducing electricity and water demands, increasing supplies, and storing more water. Recent trends towards combined cycle natural gas plants with towers has reduced water withdrawal and consumption rates since the late 1990s and is projected to further decrease to 2030. Understanding the controls on drought vulnerability of power plants and exploring various options to increase resilience is essential for continued reliable affordable electricity production in Texas.