Monday, August 8, 2011

How Saving Energy Means Conserving Water in U.S. West

How Saving Energy Means Conserving Water in U.S. West
Power and water are interconnected and that has serious consequences
for the American West as it grapples with climate change

By Daniel Glick and The Daily Climate | August 1, 2011 | 10

http://www.scientificamerican.com/article.cfm?id=how-saving-energy-means-conserving-water
ENERGY AND WATER: Power plants require cooling water and getting
water where its needed requires power in the American West--
highlighting the tight interconnection between energy and water.Image:
Elf/Wikimedia Commons
California likes to think of itself as being ahead of the curve. So
when the state set out to reduce greenhouse gas emissions, regulators
did all the right things - stringent tailpipe standards for cars,
tighter codes for buildings, higher renewable energy standards for
utilities. Then they took one of the most aggressive energy-saving
steps of all.

They started a campaign to save water.

The link between energy and water is not always apparent, but the two
are as intertwined as the hydrogen and oxygen atoms in a bottle of
Evian.

By now, everyone knows you save energy by turning out lights. And you
conserve water by taking shorter showers. But it's just as true that
saving water may be one of the most effective ways to save energy -
and vice versa. "It's a 'buy one, get one free' deal," said Douglas
Kenney, a professor at the University of Colorado Law School and the
editor of an upcoming book that explores the nexus of water and energy.

In California today, just delivering water accounts for 20 percent of
the state's energy consumption. It takes power to gather water, purify
water, and distribute water, especially in places like southern
California where water is piped hundreds of miles to supply Los
Angeles' sprawling demands.

Nationally, energy production sucks more water from freshwater sources
than any other sector except agriculture. It takes water to create the
power we use to drive our cars, transport our groceries, and run our
toaster ovens. Virtually every source of electricity in a typical
American home or manufacturing plant - whether it comes from
hydroelectricity, coal, natural gas, nuclear, biofuels, or even
concentrated solar -- also requires water. Lots of water.

That's a growing problem, because in many places, finding water for
energy isn't easy - and it's bound to get tougher as energy demands
soar and climate change alters hydrological cycles in already arid
regions. The energy sector is the fastest-growing water consumer in
the United States, according to a January 2011 Congressional Research
Service report.

Nationally, that's a challenge, but regionally it could be a calamity.
As the Congressional Research report notes, "much of the growth in the
energy sector's water demand is concentrated in regions with already
intense competition over water."

***

The connection between energy and water - and the precariousness of
that link in the western United States - is exemplified in a gigantic
plug of concrete stopping the muddy Colorado River above Las Vegas,
otherwise known as Hoover Dam. At the ceremony inaugurating the
Depression-era public works project in 1935, then-Interior Secretary
Harold Ickes noted proudly, "no better understanding of man
cooperating with nature can be found anywhere."

Hoover Dam provided the two key ingredients - water and power - that
freed the Southwest and southern California to go on a 75-year growth
spurt. Lake Mead now supplies water to more than 22 million people,
and it produces more than four billion kilowatts of electricity per
year.

But Ickes likely never imagined how quickly man's cooperation with
nature would disintegrate in the 21st century. In the American West, a
burgeoning population created a double-whammy of surging power demands
and dwindling freshwater supplies. The Colorado River, lifeblood of
seven western states, is already as overdrawn as the federal treasury.
Drought conditions during most of the 21st century have forced water
managers to plan for a day when the region's vast system of dams and
reservoirs no longer have enough water to store. Already, utilities
have to scramble to respond on days when everybody in Phoenix, Las
Vegas and Los Angeles wants to crank their air conditioners during the
same heat wave.

Sustained drought and insatiable upstream water demand have drained
Lake Mead to the point that experts are predicting it may soon be
shallow enough to be in deep trouble. Despite near record snowfalls
and runoff this year that raised its level from historic lows in
January, Lake Mead is still 113 feet below "full pool" - and is filled
to less than 50 percent of its capacity.

Three years ago researchers at Scripps Institution of Oceanography
warned Lake Mead has a 50-50 chance of running dry by 2021 and that
the reservoir's water level could dip low enough to reduce or stop
electricity production as early as 2013. Although this year's run-off
probably forestalled this dramatic assertion, utilities around the
country have already been forced to reduce or stop electrical
production because of water issues. According to a survey done in
California's 2009 Water Plan Update, states from Virginia to Nevada
and Texas to North Dakota have all curtailed energy development
projects because of water quality or quantity concerns.

***

One reason for this problem is that electricity, as we've chosen to
produce it, is pretty wet stuff. Plug an appliance into an outlet and
you might as well open a faucet as well. Running an average
refrigerator all day uses about as much water as a ten-minute shower
(without a low-flow showerhead). According to the U.S. Geological
Survey, electric power generation accounts for nearly half of the
nation's water usage; it takes on average 21 gallons of water to
produce one kilowatt hour of electricity. In the arid West, those
numbers add up. A report by Western Resource Advocates notes that
"thermoelectric power plants in Arizona, Colorado, New Mexico, Nevada,
and Utah consumed an estimated 292 million gallons of water a day in
2005 - approximately equal to the water consumed by Denver, Phoenix,
and Albuquerque, combined."

Pretty much every step of energy production requires water, from
mining to refining, processing to generation. Some of this water is
"consumed" - evaporated as steam. Some of it is returned to watersheds
in altered forms - like water heated during coal-fired electrical
production and stored in cooling towers or ponds before being released
- at higher temperatures - back into rivers. "Produced" water from
coal-bed methane extraction releases underground water with high
mineral content into watersheds. Deep drilling for seams of
underground gas deposits rely on chemicals used in "fracking fluids,"
which contaminate water sources when they leak.

Other potential fossil fuel energy sources, like oil shale, require so
much water during its production cycle that energy companies in
Colorado have stealthily acquired rights to develop hundreds of
thousands of acre feet of water, even before they've invented a viable
technology to turn that rock into oil. An acre foot of water is
325,851 gallons, or enough to cover an acre of flat farmland with
water a foot deep.

That's enough water to escalate the state's already intense water
disputes into open warfare. "If oil shale energy does become
commercially viable, it will be a huge new water drain," says Dan
Luecke, a Colorado-based hydrologist and Western water consultant.

Many current energy debates have focused on the massive carbon
footprint of fossil fuels like oil, coal and natural gas. But many
renewable sources of energy, like corn-based ethanol, have a huge and
potentially troubling "water footprint." Corn ethanol made from
irrigated crops, for example, can use more than 1,000 times more water
than oil refining, according to calculations by Sandia National
Laboratory. Industrial concentrated solar arrays can require 800
gallons of water to produce a single megawatt hour. Mike Hightower, a
senior researcher at Sandia National Laboratories in New Mexico,
cautions that reducing carbon emissions, while crucial, is just one
part of the energy equation: Virtually every time you lower the carbon
footprint in industrial energy production, he says, "you end up with a
bigger water footprint."

As planners look to the future, they have to grapple with some tough
trends: the more energy we need, the more water we need. But the
availability of fresh water has already reached crisis proportions in
many parts of the world, and some experts warn we should be more
worried about "peak freshwater" than "peak oil." According to Peter
Gleick and Meena Palaniappan, writing in the Proceedings of the
National Academy of Sciences, water availability is a growing global
problem, especially in regions like the Western U.S. where "almost all
major rivers and aquifers and already tapped out." Unlike oil, they
write in dry, understated concern, water is absolutely essential for
life. "For many uses," they conclude, "it has no substitutes."

Climate change is only going to make the water-energy balance more
precarious.

Arid mid-latitude regions like the West are warming nearly twice as
fast as the global average, according to the Rocky Mountain Climate
Organization. As the West warms, residents will need more energy to
cool living spaces and make desert cities like Tucson and Scottsdale
inhabitable - and will likely have less water to make enough
electricity to do that.

The collision of water, energy and climate change will reverberate
through public policy decisions for decades to come, with unintended
consequences at each step. Congress effectively encouraged a giant
sucking sound from Midwestern aquifers and rivers by creating massive
subsidies for corn ethanol. Concentrated solar projects, which have
received "fast-track" authority from the Obama administration, may run
into water problems before the first watts are generated. Citizen
opposition to new coal-fired power plants in places like Nevada and
Montana has focused as much on water concerns as greenhouse gas
emissions.

Global climate models predict that arid regions of the world will
become more arid as a result of rising greenhouse gas emissions.
According to the U.S. Global Change Research Program's report, Global
Climate Change Impacts in the United States, a one percent decrease in
precipitation leads to a two to three percent drop in stream flow.
Every percentage point that stream flows drop means a three percent
decline in electricity generation. The report's conclusion is as
obvious as it is ominous: "Water and energy are tightly interconnected."

Some energy sources, like rooftop photovoltaics and most wind power,
are not water hogs, but experts say they are not likely to fill the
nation's growing power needs by themselves. Conservation - both of
water and of energy, are undeniably going to be part of any future
plan, as are technological improvements in wastewater treatment and
reclamation. "People are beginning to understand that if you save
water, you save energy," says Sandia National Laboratory's Hightower.

They also need to also understand that if they save energy, they'll
save water as well. Which, in the long run, may be an even more
important thing to conserve.

Daniel Glick, a former Newsweek correspondent, is co-founder of the
Story Group (http://thestorygroup.org/) with photographer Ted Wood.
DailyClimate.org is a nonprofit news service covering climate change.

On the web:

Congressional Research Service report on water consumption (pdf)

Lake Mead water data

California's 2009 Water Plan Update (pdf)

USGS report on water and energy (pdf)

Western Resource Advocates report on shale water rights in Colorado
(pdf)

Peter Gleick, Meena Palaniappan PNAS paper

Rocky Mountain Climate Organization report (pdf)

US Global Change Research Program report

This article originally appeared at The Daily Climate, the climate
change news source published by Environmental Health Sciences, a
nonprofit media company.
________________________________________________

You received this message as a subscriber on the list: dams@list.internationalrivers.org

To be removed from the list, please visit:
http://salsa.democracyinaction.org/o/2486/unsubscribe.jsp

1 comment:

  1. This is what we can call killing two birds with one stone! Certainly, water and energy have some chemistry. In fact, water can also be used as a source of energy, and it's called hydropower.
    - Lorenza Coon

    ReplyDelete