Drought and the water–energy nexus in Texas

TLDR

Texas endured its most severe drought in 2011, with up to 100 days of triple‑digit temperatures, record electricity demand, and historically low reservoir levels. The study quantified each power plant’s water and electricity demand and supply relative to 2010, showing that natural gas—now about 50 % of Texas generation—provides drought resilience by enabling flexible gas turbines and combined‑cycle units that use roughly 30 % of the cooling water required by steam turbines. During the drought electricity generation rose 6 % and water consumption for power rose 9 %, yet plants adapted by shifting to less water‑intensive technologies, and projected reductions in water use will continue through 2030 as natural gas and renewables grow, with gas combined‑cycle plants saving 25–50 times more water than the water used in hydraulic fracturing.

Abstract

Texas experienced the most extreme drought on record in 2011 with up to 100 days of triple digit temperatures resulting in record electricity demand and historically low reservoir levels. We quantified water and electricity demand and supply for each power plant during the drought relative to 2010 (baseline). Drought raised electricity demands/generation by 6%, increasing water demands/consumption for electricity by 9%. Reductions in monitored reservoir storage <50% of capacity in 2011 would suggest drought vulnerability, but data show that the power plants were flexible enough at the plant level to adapt by switching to less water-intensive technologies. Natural gas, now ∼50% of power generation in Texas, enhances drought resilience by increasing the flexibility of power plant generators, including gas combustion turbines to complement increasing wind generation and combined cycle generators with ∼30% of cooling water requirements of traditional steam turbine plants. These reductions in water use are projected to continue to 2030 with increased use of natural gas and renewables. Although water use for gas production is controversial, these data show that water saved by using natural gas combined cycle plants relative to coal steam turbine plants is 25–50 times greater than the amount of water used in hydraulic fracturing to extract the gas.