Water and Energy: Texas Drought Reveals the Choke Point

New York Times:

AUSTIN, TEXAS — The worst single-year drought in the recorded history of Texas has caused cotton crops to wither and ranchers to sell off cattle. It may also hurt power plants, which need vast amounts of water to cool their equipment.

“We will be very concerned” if it does not rain by spring, said Kent Saathoff, an official with the Texas electric grid operator.

The worries in Texas bear out what an increasingly vocal group of researchers has been warning in recent years: that planners must pay more attention to how much water is needed in energy production.

“Water and energy are really linked,” said Henrik Larsen, a water policy expert with the DHI Group, a research and consulting firm based in Denmark. “If you save water, you save energy, and vice-versa.”

Experts call this the “water-energy nexus.” It takes huge quantities of water to produce electricity from a plant powered by nuclear energy or fossil fuels, and it also takes lots of energy to pump and process the water that irrigates fields and supplies cities.

In the United States, 4 percent of all fresh water is consumed in the energy sector, and 3 percent of all electricity used daily goes toward water and wastewater pumping, distribution, and treatment, according to Mike Hightower, a member of the technical staff at Sandia National Laboratories.

CleanTechnica:

Steve Sawyer, Secretary General to the Global Wind Energy Council (GWEC,) says, “”The global power sector is the largest industrial water user, and it has to start addressing the issue of water consumption, especially in the light of rising electricity demand, and increasing droughts created by the world’s changing climate … “To mitigate climate change, the power sector not only needs to become CO2 free, but also dramatically reduce its water consumption.” U.N. World Water Day is held annually on March 22, and in partnership with the GWEC, stresses the benefits of wind technology.

US Department of Energy estimates that 20% of wind power in the US power system by 2030 would save as much as 4 trillion gallons (15 trillion litres) of water.

Texas is not the only example.

Those that point to China’s escalating coal use as an excuse for inaction on climate change, should know that China is about to run into a wall, not with a coal shortage, but a critical water shortage.  According to wikinvest.com, 

China has 6.2% of the world’s renewable fresh water supply, yet has 21% of its population. The Northern and Western regions of China are particularly vulnerable. Southern China residents have access to over 80% of the country’s water. 67% of China’s cities are impacted by water shortages. Weather has also worsened the water shortage. China’s North China Plain has seen 7 consecutive years of drought.

Water tables are falling dramatically. Over 60% of China’s water supports agriculture. The North China Plain’s water table, where much of China’s grain products are grown, falls about 5 ft per annum. As desperate farmers use pumps to drill deeper, aquifer depletion becomes a reality.”

Researchers at Tsinghua University in Beijing recently published evidence that “without effective water-saving measures or regulations, the water demand in the coal industry could dramatically increase and probably surpass China’s water supply capacity in the near-term future, bringing great uncertainty to the sustainable development of China’s economy.”

The realities of peak oil, peak coal,(more about this in a future post) peak water, and uncertainties about natural gas make it only more urgent that investment in renewable power sources, like wind, photovoltaic, and other low water options, be accelerated.