Water Energy Matters

Issues related to the water-energy nexus

What is the government doing about this?


Inaction at the federal level
In 2005, Congress mandated a federal water and energy roadmap. The Department of Energy partially responded to the call in December 2006 with a report on the interdependency of energy and water called  “Energy Demands on Water Resources.” Yet, to date, there is still no national research program directly aimed at understanding the intimate and complex relationship between water and energy in a comprehensive way.

Growing energy demands in the arid U.S. West

The greatest increases in population growth will happen in some of the U.S.’s most water-scarce areas. (Image courtesy of National Renewable Energy Laboratory)

There is growing concern whether an appropriately-routed and affordable supply of water will exist to support the U.S.’s growing electricity demands, in particular around matching geographical water availability to energy need. For example, in the 1990’s, the largest regional population growth of 25% occurred west of the Rocky Mountains, one of the most water deficient regions in the U.S. Water consumption in the western U.S. is much higher than other regions because of farming demands. It is estimated that over one million gallons of water is needed each year to irrigate one acre of farmland in arid conditions. This means that in 2000, the majority of freshwater withdrawals (86 percent) and irrigated acres (75 percent) were in the western states.

Managing water and energy together at the state level
State lawmakers and natural resource managers have traditionally addressed water and energy as two separate issues. However, water and energy are deeply connected, so the sustainability of one requires consideration of the other. Thus, resource managers and lawmakers in many places are beginning to take a more holistic approach to the management of water and energy.

At least nine states (Arizona, California, Colorado, Connecticut, Nevada, South Dakota, Washington, West Virgina, and Wisconsin) have statutes that recognize the nexus between water and energy. A statute is legislative law. Three states in the more arid West (Arizona, California, and Nevada) have statutes that specifically refer to the use of water for electricity power generation.

Arizona’s well-known cactus-dotted landscape is an indicator of its arid climate. (Image courtesy of eHow)

In Arizona, Statute § 45-156 requires electricity facilities to request legislative authorization in order to divert water to generate over 25,000 horsepower (18,642 Megawatt-hour) of electric energy. Statute § 45-166 says that an electricity generating plant (most of which are coal-operated) can use up 34,100 acre-feet of water each year, including water used for mining, coal transportation, and ash disposal.

In California, Code § 5001 exempts individuals who extract groundwater or surface water for generating electricity from submitting a “Notice of Extraction and Diversion of Water”. In Nevada, Statute § 533.372 says the State Engineer can approve or disapprove any application of water from beneficial use to a use that generates energy that will be exported out of Nevada.

What does this mean?
In California, generating electricity is one of the few reasons that exempts individuals from notifying the state that they are diverting water and how much they’re diverting. In contrast, in Arizona and Nevada, legislation is trying to apply some limits to the amount of water that can be used for electricity generation, or at least toward electricity that leaves the state.

I suspect one of the main reasons for the contrast is resource priorities. Arizona and Nevada are two of the most arid states in the U.S.: Nevada ranks number one and Arizona fourth for the least amount of annual precipitation. Nevada’s Division of Water Resources says its mission is “to conserve, protect, manage, and enhance the state’s water resources … through the appropriation and allocation of the public waters.” Arizona’s Department of Water Resources is stronger with their intention and directly say that the state places a high priority on managing its limited water.

A San Diego convenience store without electricity during the 2011 Southwest blackout. (Image courtesy of Associated Press)

California, in contrast, does not even make the top 10 most arid states based on annual precipitation. With the California electricity crisis of 2000 and 2001 and the one more recently in 2011 fresh in memory, California officials are much more worried about managing electricity demands and do whatever is necessary to avoid perennial summer blackouts. Understandably so — the early 2000’s electricity crisis costed the state $40 to $45 billion.

Taking a much harder look
Though they exhibit a step in addressing water and energy issues together, these state-level legislation have weak influence on the impacts that conventional electricity generation has on water supply and quality. “US policy makers continue to overlook the implications of increasing water scarcity when they evaluate the use of coal and nuclear power,” says a report, “The Hidden Costs of Electricity: Comparing the Hidden Costs of Power Generation Fuels,” released in September by the Civil Society Institute.

When it comes to water impacts, the report finds that renewable energy sources have the least water impact. However, coal, nuclear, and natural gas resources have the highest hidden costs. This is worrisome since these are also the three most dominant means of producing electricity in the U.S. today.

Fracking uses large amounts of water and has contaminated ground water in many documented cases. (Image courtesy of the film Gasland)

Coal and nuclear plants use (and lose) 300-1,000 gallons of water per Megawatt-hour (MWh). However, these plants withdraw a lot more water than that for its steam heating and cooling process — anywhere from 500 to 60,000 gallons per MWh depending on the cooling system. The water that is returned to the environment is wastewater which degrades river water quality. Furthermore, the mining processes for the energy resources in these plants (coal and uranium) contaminate groundwater. For natural gas, the major water costs come from extraction processes, such as fracking and coalbed methane recovery, which require large volumes of water and contaminate ground and surface water.

Arizona is beginning to regulate how much water can be used for electricity generation. But, the water-energy nexus issue is far more complex:

  • How can we ensure the quality of water that returns to the environment after it’s used by power plants?
  • How can power plants be more water efficient so there aren’t such vast differences in the amount of water required for cooling?
  • How much water should be used for extraction and mining?
  • How can these processes be better regulated to minimize contamination effects?
  • How do we include water impacts to strengthen transitions to renewable energy sources?

All these are questions that have yet to be addressed by legislation and government management in an integrated way both at the state and national levels.


3 thoughts on “What is the government doing about this?

  1. I’ve been looking into the amount of water that fracking requires. It’s enormous! It’s interesting to think about where new energy extraction/processing facilities will get their water in the West in areas/states where all of the water is already or nearly appropriated. At least in the front range, it seems that fracking companies are buying or leasing water from municipalities and agriculture. It’s scary to think that communities might be willing to sell off water that they may need in the future to meet household water needs.

    I also appreciated your point about the temperature of return water from the electricity generation. Even though it is likely counted as a non-consumptive use, it is definitely not returned to the stream in the same condition.

    Thanks for the post!

  2. I liked your point about the way that different states prioritize energy resources versus water resources — with California having energy (electricity) on its mind more so than water, and Arizona the other way around. You get at one of the things I think is fascinating but understudied about the Energy-Water Nexus (I’m hoping to change that by writing about it myself!), and that’s the way that conflicts between energy and water resources reveal to us the different ways we value each of them. Fracking is a great example. Colorado’s Front Range communities were utterly oblivious of their water resources until natural gas rigs showed up. The hydrologist in me cheers the fact that residents of Erie, for example, are starting to become aware of where their water comes from. But I also despair that it takes such an extreme case to impress the importance of the hydrologic cycle on people. Anyway, thanks so much for the post!

  3. This is really interesting. Despite all my work in energy, I’ve never really looked at the energy water nexus, aside from the groundwater issues associated with fracking. That so much water is used for conventional generation is just another advantage of renewables. I wonder how much water plays into the generation costs of these fossil fuel plants. If water somehow (you can use your imagination here) had a higher price associated with its use, potentially a tiered rate structure like I see on my Xcel bill, would power generation companies be able to create and use steam more efficiently. In the long run, perhaps. In the short run, input prices would increase, making renewables more cost competitive with the incumbent fossil fuel generators. In Colorado, from a policy perspective, this (i.e. putting a price on excessive water use) could be an interesting way to promote renewables while also conserving water. I’d love to see that happen!

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