Energy production from almost all technologies depends on large volumes of water.  Competition for scarce water supplies, particularly in the West, grows more intense as demand for both energy and water increases.  An obvious Northwest example is a decade-old federal case over whether elements of the Federal Columbia River Power System can coexist with salmon, the outcome of which affects the economic vitality of the entire region.  Apart from hydropower, water used in energy production may be water not used for agriculture, other industries, drinking, bathing, recreation and fish.  But are energy and water really a zero-sum game?  So far, the conflicts have been manageable, but are we fast approaching an era of irreconcilable conflicts?  

Water may be the first source of energy employed by humans other than muscle power.  Paddle wheels in a running stream allowed the grinding of grains on a commercial scale, leading to the powering of more sophisticated machinery, and finally to universal electrification.  Water power is renewable, non-consumptive, efficient, non-greenhouse gas emitting, cheap to operate, and when combined with storage, load following.  Further, water stored for production also provides irrigation, recreation and flood control, and makes river transportation of goods possible.  Water power also has an increasingly crucial role to play in the integration of wind power into the electric grid. 

On the flip side, hydropower associated with dams can block fish passage, change the chemistry and character of streams and otherwise disrupt the life cycles of aquatic species.  The economy in the Pacific Northwest is entirely reliant on low-cost, abundant hydropower and the region is grappling with how best to mitigate the ecological side effects.

In addition to providing energy directly, water is an essential component of electric generation from a wide range of technologies.  Excess heat from thermal generating plants—gas, oil, coal, nuclear, biomass and thermal solar to name a few—must be dissipated, and water is generally the most efficient means.  Prodigious volumes of water are consumed for this purpose everywhere, including the arid West; some projects operate on a closed loop system, others do not.  Water is required to grow, harvest, mine and refine raw materials used in energy production. 

Large volumes of water are also needed for the recovery of fossil fuels.  Extraction of shale oil and natural gas depends upon hydraulic fracturing, or fracking, of geologic formations.  The amount of water needed for fracking is enough to cause local concern about the effect on water supplies.  Further, chemicals added to the fracking fluid raise the specter of widespread groundwater contamination.  Some of this natural gas will be transported to LNG processing facilities, which also require water cooling.

How we manage these conflicting aspects is the major natural resources policy issue of our times.  More efficient and multiple uses of water is part of the answer.  Another element is taking a watershed-wide view when considering new water supply development so that ecological impacts can be properly assessed, avoided, and if necessary, mitigated.  Ecosystem services markets are emerging to facilitate watershed scale restoration of habitat as a means of resolving regulatory problems.  But that’s the subject of a future blog.