Water Energy Matters

Issues related to the water-energy nexus


Desalination, part I: The challenges of applying ethics in water scarcity

One of the most iconic movie of the 1990’s that foreshadows what the harsh environments of a resource-scarce future may look like is Waterworld. The movie opens with a voice-over narrator explaining that the polar ice caps have melted and the planet is covered by water. The camera pans from an image of Earth into a lone trimaran sailing in a vast, endless sea.

The harsh environmental future of Waterworld. (Video courtesy of YouTube)

Within a few shots, the opening scene has not only established a vibrant image of an extreme and dire future, but has illustrated the conspicuous lack of basic resources that most of us in developed countries take for granted — things such as potable water; land for growing food and raising animals; and means of electricity generation. The male protagonist Mariner, in his post-apocalyptic warrior dress, pees into a small container. He then pours the urine into a rudimentary, homemade filter of funnels and gizmos, and drinks what comes out the other side — a process called desalination.

Drinking one’s own (albeit filtered) urine signals a certain direness under conditions of extreme survival. But desalination — the process by which unpotable water, such as seawater, brackish water, and wastewater, is purified into freshwater for human consumption and use — is not some far-fetched technology we will eventually need in a distant future.

Desalination’s recent global development
Desalination technology has been used for centuries, if not longer, largely as a means to convert seawater to drinking water aboard ships and carriers. Advances in the technology’s development in the last 40 years has allowed desalination to provide water at large scale.

From a global perspective, desalination technology is applied for several purposes: providing freshwater for industrial sectors; supplying drinkable water for the domestic and public sectors; and acquiring water for emergency situations, such as army and refugee operations.

Desalination plays a particularly crucial role in sustaining life and economy in the Persian Gulf. According to Corrado Sommaria, the president of the International Desalination Association (IDA): “Some countries in the Gulf rely on desalination to produce 90 percent or more of their drinking water, and the overall capacity installed in this region amounts to about 40% of the world’s desalinated water capacity.” Much of this is in Saudi Arabia, Kuwait, the United Arab Emirates, Qatar, and Bahrain.

global desalination capacity

Global desalination capacity by country and total capacity. (Image courtesy of Desalination: A National Perspective)

The remaining global capacity is mainly in North America, Europe, Asia (which each have about 15 percent), and North Africa (which has six percent). (A facility’s rated capacity is the full output it is technically capable of, though in reality, it usually produces under that rated value.)  Australia‘s capacity is also increasing substantially. Global desalination capacity has been increasing dramatically since 1960 to its 2008 value of 42 million cubic meters of water daily (m3/day). Of this cumulative capacity, approximately 37 million m3/day is in use. From the above graph, we can see that worldwide desalination capacity more than doubled between 1993 and 2003, and continues to grow steadily today.

Proponents and critics of desalination
Estimates indicate that, by 2025, 1.8 billion people will be living in regions with absolute water scarcity, and two-thirds of the world population could be under stress conditions. Desalinated water is possibly one of the only water resources that does not depend on climate patterns. Desalination appears especially promising and suitable for dry regions.

In one of the country’s biggest infrastructure projects in its history, Australia’s five largest cities are spending $13.2 billion on desalination plants. In two years, when the last plant is scheduled to be up and running, these cities will draw up to one-third of their water from the sea.

Proponents of desalination, like IDA, argue that it sustains population growth, creates jobs, and even supports the development of  energy industries (such as the oil and gas industries in the Middle East). Desalination stops dependence on long-distance water sources and prevents local traditional water sources from being over-exploited. Furthermore, research and development has made great strides in making desalination plants increasingly energy efficient and cost-effective.

However, there are a number of desalination plants worldwide that have been described as uneconomical and unproductive.  Many environmentalists and economists oppose any further expansion of desalination because of its price and effects on the environment. Energy is the most expensive component of running a desalination plant; it is often responsible for one-third to more than half of the cost. Therefore, the cost of desalinated freshwater is more vulnerable to the fluctuation of energy prices than any other water source.

A desalination intake pipeline near Nuweiba, Egypt. (Image courtesy of prilfish)

A desalination intake pipeline near Nuweiba, Egypt. (Image courtesy of prilfish)

Environmentally, desalination plants emits large amounts of greenhouse gas emissions because they are so energy-intense. Furthermore, they degrade marine environments through both the intake and discharge processes. Marine organisms such as invertebrates, fish, and even mammals are killed on the intake screen and smaller organisms, such as eggs, larvae, and smaller fish, that are able to pass through the screen are killed during processing stages. After separating the impurities from the water, the plant discharges the waste, also known as brine, back into the sea. Because brine contains much higher concentrations of salt, it causes harm to the surrounding marine habitat.

In Australia, the mega infrastructure project is drawing fierce criticism and civic protests. Many citizens are angry about rising water bills and environmentalists are wary of the plants’ effect on the climate. Australia relies heavily on coal to generate most of its electricity and is already a major emitter of greenhouse gases — the principle cause of climate change. Ironically, one of the main reasons the country is in need of freshwater is because it’s still recovering from a decade-long drought that the government says was deepened by climate change. Therefore, desalination, which initially appears as an answer for providing freshwater, may in the long run exacerbate the intertwined energy- and water-scarcity cycle.

As scarcity increasingly becomes reality, an appeal to ethics will be challenging
The sentiments of the anti-desalination campaigner in the video below echoes this irony: “It is by a mile the most environmentally-unsound way toward security.” He and other critics say that more environmentally-friendly methods should be exhausted before resorting to desalination. These include mandating more efficient appliances, using less water, or recycling used water.

Australia’s desalination plant provides controversial solution to one of the world’s driest countries. (Video courtesy of Al Jazeera English)

When a society is accustomed to a certain level of access to a resource, it’s hard to ask its citizens to lower their consumption or reuse water based on the argument that it is an ethical choice. In many instances, we observe individual behaviors change in response to policy mandates or market costs. But when can we say that we’ve exhausted all other ways that are less environmentally-damaging? How much should consumption be reduced? How do we decide which water needs are necessary (e.g., water for drinking, agriculture, electricity generation) and which ones aren’t (e.g., water for golf courses) for a certain quality of life?

Waterworld highlights the harsh decisions people face in a scarce-resource future because of the heightened awareness for survival. Pirates raid small pockets of human settlements for resources, they have no qualms about kidnapping a child for the map tattooed on her back, and paranoid atoll residents are willing to kill the Mariner out of distrust. Violence pervades and there is little sense of civility or ethical codes of conduct.

Though the movie is suggested to take place in 2500, it is not hard to imagine that tensions and battling interests over resources will intensify in the not-so-distant future. Making ethical decisions about fair and equal distribution of resources is a challenge today, and will become increasingly more difficult as those resources diminish — even with the most sophisticated of technological developments.


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.


The need for a change in understanding

Last year, Texas experienced the worst single-year drought in recorded history. Ken Saathoff, an official with the state electric grid operator, said “we will be very concerned” if  it does not rain by spring. This seems odd at first. Why would someone who works in the electricity sector care so much about rainfall and drought?

Examples of interdependency between the water and carbon cycles. (Image courtesy of National Conference of State Legislatures)

Saathoff’s concern highlights the important relationship between two resources that has been gaining much attention (and concern) in recent years. Water and energy were once thought of and treated as separate issues. Growing population demands and resource shortages, however, underscores how much these two resources are interlinked.

Energy means a lot of things. We usually say we need to eat so we have the energy to do work. And that is what energy is fundamentally: the ability to do work. In this particular post, we’ll be talking about a specific kind of energy: electric energy. Electric energy plays an important role in almost every aspect of our lives: it lights stores, makes factories work, keeps the refrigerator cold, and powers our electronic devices.

What may not be as apparent is that electric energy also helps bring the water we use. The intersection of water and energy issues is known as the “water-energy nexus.” It points to how much energy is needed to pump, process, transfer, store, and dispose water. It also shows how much water is used to extract, generate, and transmit energy.

An overview of the process of extracting, generating, and transmitting electrical energy, and some of water’s role in the process. (Video courtesy of Energy Now!)

Most sources (including Sandia National LaboratoriesNational Conference of State Legislatures, and Circle of Blue) say that about 4% of national electricity use goes to moving and treating water. In some regions, this percentage is much higher. For example, the California Energy Commission reports water-related energy use constitute 19% of the state’s electricity and 32% of its natural gas. A large part of the issue is that where water is needed is not always where it is most abundant, requiring large amounts of energy to move water over distances.

California Aqueduct

Large, long-distance water aqueducts transport water to Southern California, requiring much energy along the way. (Photo courtesy of Wikimedia Commons.)

Generating and distributing energy also require large amounts of water. The Network for Energy Choices says that U.S. power plants use more fresh water than irrigation while Sandia National Laboratories says that agricultural water use is still the highest. Despite arguments in ranking, most organizations (including Network for Energy Choices, Sandia National Laboratories, and National Renewable Energy Lab) agree that U.S. power production requires 140 to 200 billion gallons of water daily. That’s 200,000,000,000 gallons! This accounts for almost 50% of all national freshwater withdrawals.

This means that in times of drought, when rivers or reservoirs dry up, power plants in hard-hit areas may not have enough water to operate. Water is also crucial for other parts of energy production, including energy extraction, refining and processing, and transportation. For extraction, drawing oil and natural gas from the ground with hydraulic fracturing techniques requires copious amounts of water. For refining and processing, water is needed for refining oil and gas, as well as for growing and refining biofuels. For transportation, water is needed for hydrostatic testing of energy pipelines.

Given water’s tremendous role in energy production, it is no wonder that Saathoff was closely watching the Texas skies for rainfall last September. If drought conditions continued into spring, it would have major impacts on the state electric grid.

Director of the Stockholm International Water Institute Jakob Granit says that given the scarcity of water resources, stronger regional cooperation will be important in making sure power plants are located in the best places. The implication is that power plants should be located near abundant water sources so that 1) they are not as susceptible to climate change, and 2) less energy will be used to transport water over long distances.

Granit’s sentiments also point to an increasing trend of local and regional planners who realize the importance of examining water and energy issues together. The next blog post will look at what efforts are happening at the regional, state, and federal levels to address this critical and dynamic relationship. Stay tuned!