National Geographic News
A coal power plant.

The global increase of coal power, along with the coal industry's adoption of new technologies, will drive the largest share of water consumption for energy use through 2035, according to the IEA. Pictured: Germany's Jaenschwalde coal plant.

Photograph by Bernhard Classen, Alamy

Marianne Lavelle and Thomas K. Grose

For National Geographic News

Published January 30, 2013

The amount of fresh water consumed for world energy production is on track to double within the next 25 years, the International Energy Agency (IEA) projects.

And even though fracking—high-pressure hydraulic fracturing of underground rock formations for natural gas and oil—might grab headlines, IEA sees its future impact as relatively small.

By far the largest strain on future water resources from the energy system, according to IEA's forecast, would be due to two lesser noted, but profound trends in the energy world: soaring coal-fired electricity, and the ramping up of biofuel production.


Two pie charts show the share of different fuels for water consumption, as projected by the International Energy Agency.

National Geographic

If today's policies remain in place, the IEA calculates that water consumed for energy production would increase from 66 billion cubic meters (bcm) today to 135 bcm annually by 2035.

That's an amount equal to the residential water use of every person in the United States over three years, or 90 days' discharge of the Mississippi River. It would be four times the volume of the largest U.S. reservoir, Hoover Dam's Lake Mead.

More than half of that drain would be from coal-fired power plants and 30 percent attributable to biofuel production, in IEA's view. The agency estimates oil and natural gas production together would account for 10 percent of global energy-related water demand in 2035. (See related quiz: "What You Don't Know About Biofuel.")

Not everyone agrees with the IEA's projections. The biofuel industry argues that the Paris-based agency is both overestimating current water use in the ethanol industry, and ignoring the improvements that it is making to reduce water use. But government agencies and academic researchers in recent years also have compiled data that point to increasingly water-intensive energy production. Such a trend is alarming, given the United Nations' projection that by 2025, 1.8 billion people will be living in regions with severe water scarcity, and that two-thirds of the world's population could be living under water-stressed conditions.

"Energy and water are tightly entwined," says Sandra Postel, director of the Global Water Policy Project, and National Geographic's Freshwater Fellow. "It takes a great deal of energy to supply water, and a great deal of water to supply energy. With water stress spreading and intensifying around the globe, it's critical that policymakers not promote water-intensive energy options."

Power Drunk

The IEA, established after the oil shocks of the 1970s as a policy adviser on energy security, included a warning on water in a special report within its latest World Energy Outlook released late last year. "A more water-constrained future, as population and the global economy grow and climate change looms, will impact energy sector reliability and costs," the agency said.

National Geographic News obtained from IEA a detailed breakdown of the figures, focusing on the agency's "current policies" scenario—the direction in which the world is heading based on current laws, regulations, and technology trends.

In the energy realm, IEA sees coal-powered electricity driving the greatest demand for water now and in the future. Coal power is increasing in every region of the world except the United States, and may surpass oil as the world's main source of energy by 2017. (See related interactive map: The Global Electricity Mix.)

Steam-driven coal plants always have required large amounts of water, but the industry move to more advanced technologies actually results in greater water consumption, IEA notes. These advanced plants have some environmental advantages: They discharge much less heated water into rivers and other bodies of water, so aquatic ecosystems are protected. But they lose much more water to evaporation in the cooling process.

The same water consumption issues are at play in nuclear plants, which similarly generate steam to drive electric turbines. But there are far fewer nuclear power plants; nuclear energy generates just 13 percent of global electricity demand today, and if current trends hold, its share will fall to about 10 percent by 2035. Coal, on the other hand, is the "backbone fuel for electricity generation," IEA says, fueling 41 percent of power in a world where electricity demand is on track to grow 90 percent by 2035. Nuclear plants account for just 5 percent of world water consumption for energy today, a share that is on track to fall to 3 percent, IEA forecasts. (See related quiz: "What You Don't Know About Water and Energy.")

If today's trends hold steady on the number of coal plants coming on line and the cooling technologies being employed, water consumption for coal electricity would jump 84 percent, from 38 to 70 billion cubic meters annually by 2035, IEA says. Coal plants then would be responsible for more than half of all water consumed in energy production.

Coal power producers could cut water consumption through use of "dry cooling" systems, which have minimal water requirements, according to IEA. But the agency notes that such plants cost three or four times more than wet cooling plants. Also, dry cooling plants generate electricity less efficiently.

The surest way to reduce the water required for electricity generation, IEA's figures indicate, would be to move to alternative fuels. Renewable energy provides the greatest opportunity: Wind and solar photovoltaic power have such minimal water needs they account for less than one percent of water consumption for energy now and in the future, by IEA's calculations. Natural gas power plants also use less water than coal plants. While providing 23 percent of today's electricity, gas plants account for just 2 percent of today's energy water consumption, shares that essentially would hold steady through 2035 under current policies.

The IEA report includes a sobering analysis of the water impact of carbon capture and sequestration (CCS) technology. If the world turns to CCS as a way to cut greenhouse gas emissions from coal plants, IEA's analysis echoes that of outside researchers who have warned that water consumption will be just as great or worse than in the coal plants of today. "A low-carbon solution is not necessarily a low-water solution," says Kristen Averyt, associate director for science at the Cooperative Institute for Research in Environmental Sciences at the University of Colorado. However, based on current government policies, IEA forecasts that CCS would account for only 1.3 percent of the world's coal-fired generation in 2035. (See related story: "Amid Economic Concerns, Carbon Capture Faces a Hazy Future.")

Biofuel Thirst

After coal power, biofuels are on track to cause the largest share of water stress in the energy systems of the future, in IEA's view. The agency anticipates a 242 percent increase in water consumption for biofuel production by 2035, from 12 billion cubic meters to 41 bcm annually.

The potential drain on water resources is especially striking when considered in the context of how much energy IEA expects biofuels will deliver—an amount that is relatively modest, in part because ethanol generally produces less energy per gallon than petroleum-based fuels. Biofuels like ethanol and biodiesel now account for more than half the water consumed in "primary energy production" (production of fuels, rather than production of electricity), while providing less than 3 percent of the energy that fuels cars, trucks, ships, and aircraft. IEA projects that under current government policies, biofuels' contribution will edge up to just 5 percent of the world's (greatly increased) transportation demand by 2035, but fuel processed from plant material will by then be drinking 72 percent of the water in primary energy production.

"Irrigation consumes a lot of water," says Averyt. Evaporation is the culprit, and there is great concern over losses in this area, even though the water in theory returns to Earth as precipitation. "Just because evaporation happens here, does not mean it will rain here," says Averyt. Because irrigation is needed most in arid areas, the watering of crops exacerbates the uneven spread of global water supply.

Experts worry that water demand for fuel will sap water needed for food crops as world population is increasing. "Biofuels, in particular, will siphon water away from food production," says Postel. "How will we then feed 9 billion people?" (See related quiz: "What You Don't Know About Food, Water, and Energy.")

But irrigation rates vary widely by region, and even in the same region, farming practices can vary significantly from one year to the next, depending on rainfall. That means there's a great deal of uncertainty in any estimates of biofuel water-intensity, including IEA's.

For example, for corn ethanol (favored product of the world's number one biofuel producer, the United States), IEA estimates of water consumption can range from four gallons to 560 gallons of water for every gallon of corn ethanol produced. At the low end, that's about on par with some of the gasoline on the market, production of which consumes from one-quarter gallon to four gallons water per gallon of fuel. But at the high end, biofuels are significantly thirstier than the petroleum products they'd be replacing. For sugar cane ethanol (Brazil's main biofuel), IEA's estimate spans an even greater range: from 1.1 gallon to 2,772 gallons of water per gallon of fuel.

It's not entirely clear how much biofuel falls at the higher end of the range. In the United States, only about 18 to 22 percent of U.S. corn production came from irrigated fields, according to the U.S. Department of Agriculture. And the remaining water in ethanol production in the United States—the amount consumed in the milling, distilling, and refining processes—has been cut in half over the past decade through recycling and other techniques, both industry sources and government researchers say. (One industry survey now puts the figure at 2.7 gallons water per gallon of ethanol.) A number of technologies are being tested to further cut water use.

"It absolutely has been a major area of focus and research and development for the industry over the past decade," says Geoff Cooper, head of research and analysis for the Renewable Fuels Association, the U.S.-based industry trade group. "Our member companies understand that water is one of those resources that we need to be very serious about conserving. Not only is it a matter of sustainability; it's a matter of cost and economics."

One potential solution is to shift from surface spraying to pumped irrigation, which requires much less water, says IEA. But the downside is those systems require much more electricity to operate.

Water use also could be cut with advanced biofuels made from non-food, hardy plant material that doesn't require irrigation, but so-called cellulosic ethanol will not become commercially viable under current government policies, in IEA's view, until 2025. (If governments enacted policies to sharply curb growth of greenhouse gas emissions, IEA's scenarios show cellulosic ethanol could take off as soon as 2015.)

Fracking's Surge

Fracking and other unconventional techniques for producing oil and natural gas also will shape the future of energy, though in IEA's view, their impact on water consumption will be less than that of biofuels and coal power. Water consumption for natural gas production would increase 86 percent to 2.85 billion cubic meters by 2035, when the world will produce 61 percent more natural gas than it does today, IEA projects. Similarly, water consumption for oil production would slightly outpace oil production itself, growing 36 percent in a world producing 25 percent more oil than today, under IEA's current policies scenario.

Those global projections may seem modest in light of the local water impact of fracking projects. Natural gas industry sources in the shale gas hot spot of Pennsylvania, for instance, say that about 4 million gallons (15 million liters) of water are required for each fracked well, far more than the 100,000 gallons (378,540 liters) conventional Pennsylvania wells once required. (Related: "Forcing Gas Out of Rock With Water")

IEA stresses that its water calculations are based on the entire production process (from "source to carrier"); water demand at frack sites is just one part of a large picture. As with the biofuel industry, the oil and gas industry is working to cut its water footprint, IEA says. "Greater use of water recycling has helped the industry adapt to severe drought in Texas" in the Eagle Ford shale play, said Matthew Frank, IEA energy analyst, in an email.

"The volumes of water used in shale gas production receive a lot of attention (as they are indeed large), but often without comparison to other industrial users," Frank added. "Other sources of energy can require even greater volumes of water on a per-unit-energy basis, such as some biofuels. The water requirements for thermal power plants dwarf those of oil, gas, and coal production in our projections."

That said, IEA does see localized stresses to production of fossil fuels due to water scarcity and competition—in North Dakota, in Iraq, in the Canadian oil sands. "These vulnerabilities and impacts are manageable in most cases, but better technology will need to be deployed and energy and water policies better integrated," the IEA report says. (See related story: "Natural Gas Nation: EIA Sees U.S. Future Shaped by Fracking.")

Indeed, in Postel's view, the silver lining in the alarming data is that it provides further support for action to seek alternatives and to reduce energy use altogether. "There is still enormous untapped potential to improve energy efficiency, which would reduce water stress and climate disruption at the same time," she says. "The win-win of the water-energy nexus is that saving energy saves water."

This story is part of a special series that explores energy issues. For more, visit The Great Energy Challenge.

Osmand Charpentier
Osmand Charpentier

The graph shown in this article, is proof that energy information is being funded by the arms business. Presents only the consumption of fuels to produce electricity (which is only 15% of all energy used by our civilization). The nuclear strangely appears as the only carbon-free, and hydroelectric as nonexistent.

Our civilization needs 7 times more electricity than that produced at present; and so with recyclable fuels produce energy and water. Additionally, also returned to ground, the "CO2" that we have introduced to the atmosphere from burning fossil fuels.

The production of this energy is already possible: the oceanogenic power of Panama. I apologize that seems propaganda, as I have been accused by those who earn a lot of money betray their own kind. So that they have peace, I inform them that you have achieved I do not have that feed my large family. And if we can overcome envy, we will recognize the importance of the matter.  

It's hydropower: enough for the whole planet, and for 600 years or more, and very cheap: less than 1 cent a kilowatt-hour on-site.

Make an electrical transmission line from Panama to Texas, to bring all that power that need and will need USA, is cheaper, cleaner and smarter, than an oil pipeline from Canada to the USA, which only bring less than 1% of the energy that used the past century USA.

Sid Abma
Sid Abma

Lets Recover the Water from the Combustion of Natural Gas, and utilize it.

Saving Energy Saves Water. 

Apply the technology of Condensing Flue Gas Heat Recovery. Why combust energy and waste 60% or more into the atmosphere as HOT exhaust. How does this effect Global Warming?

The DOE states that for every 1 million Btu's of heat energy recovered from these waste exhaust gases, and this recovered energy can be utilized efficiently, 117 lbs of CO2 will NOT be put into the atmosphere.

Instead of blowing a lot of Hot energy into the atmosphere, recover and utilize the heat energy, and vent COOL energy into the atmosphere.

America has Wasted so much Energy for so many years. It's time for a Radical Change to Our Energy Use.                                               Lets teach America How To Use It's Energy Efficiently ~ For Our Climate, and our childrens and great grand childrens sake.

Sid Abma
Sid Abma

Lets Recover the Water from the Combustion of Natural Gas, and utilize it.

Saving Energy Saves Water. 

Apply the technology of Condensing Flue Gas heat Recovery

Kyle E Murray
Kyle E Murray

The article states that the best way to reduce water consumption for generating electricity is to switch to alternative fuels.  This is a dangerous statement because water consumption would have to be examined for the entire life cycle of the fuel.  Some fuels may consume more water in a different phase of their life-cycle.  Also, let's not forget the idea of reducing demand via energy conservation which results in lower overall water consumption.  Electricity consumption in a single household can be reduced substantially ( and result in less water use by the utility if they adjust production to meet lesser demand.

Osmand Charpentier
Osmand Charpentier

Currently,satellite altimetry, measured the effect of cosmic hydraulics of our planet in Panama, a head of  0.3 to 14 meters, separated 70 kilometers (44 miles). When priming any flow, will happen the same as occurs in a centrifugal pump, which is nothing more that a chain reaction that will precipitate an energy in equilibrium that is front of our noses.

This is our discovery, OCEANOGENIC POWER.

The Freemasonry, which being expanded the Panama Canal, to continue to use 63 millions barrels (2000 millions gallons) per day of freshwater, ONLY TO MOVE BOATS, put me off my job of university professor, and as engineer, outside the university, because its philosophical fanaticism is ridiculed by this discovery and my big family.

This shows, again, the true reason of the suffering in any civilization.

At a cost of 1 cents per kwh, and the new HTS lines, makes available to all present civilization, enough, clean energy. 

With these costs and abundance, can be electrolysed at 200 bar, onsite water to produce hydrogen and oxygen that it needs, like example, the existing USA transport: 33 TWH per day

Although it would be much easier, and would reach for the whole world, if, while we build the first OCEANOGENIC POWER plant: we increase the efficiency for move, our civilization, from the current 3% to 30%; through electric drive. We wanted to consider the use of brakes. 

With terrestrial Cryogenic nitrogen plants, and easy modifications to install on floating offshore platforms, or for take care of thunderstorms: semi or fully immersed; superconducting lines, underground or underwater, can carry from Panama, all the OCEANOGENIC POWERnecessary on any, or all continents, both for electricity as for distill, onsite hydrogen and oxygen, or any green fuel. 

With superconducting transformers, connected as directional couplers, and using perfect loads that consume electrical energy distilland, of seawater, hydrogen and oxygen, is unnecessary to find a way of fault interrupt to the transmission of large amounts of electricity. 

And if the generation is, in small stages, as is the case of the first power plant to extract OCEANOGENIC POWER in Panama, there is no obstacle to send already, clean energy to any market of our planet, and distilling on site, fuels requiring the respective markets or last mile users. 

From Panama to USA, the superconducting transmission line wouldcost 2 billion to Florida, 3 to Texas, and 5 to California.To Japan or China, via USA, 10 billion should be increased more. To Spain; and therefore Europe: would be 8 billion. 

And the CIF cost of each kilowatt-hour will be less than 5 cent of a dollar. 

When I speak of superconducting transformers connected as directional couplers, I suggest transmit not DC, but rather, at a frequency that line, super long, measure half the respective wavelength. For example, from Panama to USA, would be 50 Hz, and from Panama to Spain,18.75 Hz. 

Then we can have control of failures, even faster than disconnecting the lines. 

The requirement of the U.S. electrical code of disconnecting power transmission when there are failures, it is anachronistic facing the new IT. This is hampering, foolishly, the development of transmission lines with higher capacity, that superconductors; the technology of: HVDC lines, and renewable energy fields, allows and needs. The IT, allows transferring energy towards controlled loads, and even useful; much faster, and much less traumatic, that disconnecting the line.

And there are also, for the last days, of those who want continue burning carbon: in the hydraulic turbines output in the tropics, methane occurs 300 times cheaper and 1000 times cleaner than any other way. And without any drop of water.

Osmand Charpentier
Osmand Charpentier

Will not occur: not only for energy but also that will not be used, nor to pollute water by fraking; since all hydropower, especially in the tropics, produces methane, 300 times cheaper than fracking.

The reason: the OCEANOGENIC POWER of Panama :

The Earth is a giant centrifugal hydraulic pump without flow. Therefore, we can consider any of these, as analysis model. 

No matter their inefficiency, when there is no flow of water: the efficiency is zero, and all the energy in the shaft, is lost in heat or internal energy, and self-recirculation. When the flow rate increases, so does the efficiency until it reaches its maximum; being transferred more energy from the shaft, and lowering the energy loss. That is, one flow is primed, which implies, a percentage of the total energy of shaft. 

The rotational energy of our planet is 63 yottawatt-hour, at 1% efficiency, we would have at our disposal 630 zettawatt-hour.

Also, there are estimates of the energy in the powerful, ocean currents, that I think, the most powerful are 4; already such estimates of lost energy (370 Tw) is enough to justify our discovery. But the interesting thing is that, until the more inefficient, centrifugal pumps on our planet, if its impeller rotates, its efficiency is not less than 1% . Why think that the earth not have this efficiency, in the worst case?

Anyway, this is enough clean energy: for electricity and to keep moving to our civilization.

Bob Damrau
Bob Damrau


Being Energy Efficient needs to take on a whole new meaning.

Energy generation, distribution and consumption balanced against strategic path of resource use.     

Sid Abma
Sid Abma

Natural gas is the America's energy of the future, and with the technology of hydraulic fracturing, natural gas will hopefully become available in many other parts of the world.

The great thing about natural gas is it is a "clean" fuel, and with the technology of Condensing Flue Gas Heat Recovery this natural gas can be consumed to well over 90% energy efficiency, greatly reducing global warming and CO2 emissions.

Then there is all the WATER that is being created during this heat recovery process. This distilled water is very usable. There is in combusted natural gas about 2 metric tons of water for every metric  ton of natural gas combusted with atmospheric oxygen.

The world is being faced with many challenges, and the sooner technologies like the above are implemented, the longer our natural gas will be able to provide to the world clean energy for producing electricity and everything else we all consume every day. Being Energy Efficient needs to take on a whole new meaning.

Bob Damrau
Bob Damrau

This article points out an upside down national/global energy and natural resource policies.  

David Zetland
David Zetland

Obviously  a good time to start pricing water in line with its scarcity. Energy firms can pay -- or they will find ways to use less water. 

David at aguanomics

mike walsh
mike walsh

My concern with Frac'ing is 15 million gallons is pumped into each well but a large amount of this water is lost from the evaporation cycle it is locked underground.

Jon Sheldon
Jon Sheldon

When calculating the amount of water required by frac'ing (spelled correctly) one must take into account the ratio of water used to hydrocarbons produced.  You can't compare a prolific shale well to a much lower producing conventional shallow well.  Shale wells actually use less water to extract a comparable amount of hydrocarbons.

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