Water Surge:
Hydropower, once shunned because of environmental concerns, is making
a comeback
* SEPTEMBER 13, 2010
By STEPHANIE SIMON
LEADVILLE, Colo.�The giant pipes wheeze and rumble, the whoosh of
water coursing through them as noisy as a freeway. The Mount Elbert
hydropower plant high in the Rocky Mountains isn't much to look at�or
listen to. But to true believers, it's a road map to a greener future.
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HYDRO
Larissa Bender, Bureau of Reclamation
Hydropower, shunned just a few years ago as an environmental scourge,
is experiencing a remarkable resurgence in the U.S. Dams are still
viewed warily; in fact, Congress is considering dismantling four
hydroelectric dams blamed for depleting salmon in the Klamath River
basin in southern Oregon and northern California.
But engineers and entrepreneurs are pressing an alternative view of
hydropower that doesn't involve new dams. They argue that plenty of
efficient, economical energy can be wrung from other water resources,
including ocean waves, free-flowing rivers, irrigation ditches�even
the effluent discharged from wastewater treatment facilities.
There's a surge of interest, too, in adding small power plants to dams
built years ago for flood control or navigation�as well as in turning
reservoirs into battery packs of sorts, releasing energy when the grid
needs it most.
Globally, hydropower provides 16% of electricity, slightly more than
nuclear power and closing in on natural gas, according to the London-
based International Hydropower Association.
In the U.S., by contrast, hydropower now provides about 7% of
electricity generation. All other renewable sources combined account
for about 3%.
Even without building large dams, expanding efforts to draw power from
water could add 40,000 megawatts to the grid by 2025, says the
Electric Power Research Institute, a nonprofit research firm in Palo
Alto, Calif. That's the equivalent of putting at least two dozen new
nuclear power plants online.
Pouring It On
Such estimates are stirring action. The U.S. Department of Energy
spent nothing on hydropower research as recently as 2007 but allocated
$50 million this year. The Federal Energy Regulatory Commission issued
50 preliminary permits for small hydro projects last year, up from 15
in 2007. At least two dozen states have mandated that utilities draw
more power from renewable sources�and many include small hydropower as
an option, along with wind and solar. Colorado Gov. Bill Ritter
recently announced an agreement between his state and the federal
government that will streamline the permitting process for developing
small hydropower projects in Colorado.
The Department of Energy estimates a new hydro project in 2016 would
generate power at a cost of $120 per megawatt-hour. By contrast, the
cost per megawatt-hour would be $150 at a wind farm going online that
year and nearly $400 at a photovoltaic solar array. (Those figures
don't take into account various tax incentives meant to offset the
cost of renewable energy, especially wind and solar.)
Hydro also has technical advantages over other renewables. Daily water
flow in many areas is far more predictable than wind or sunshine. It's
relatively easy to store the energy pent up in water so it can be
released when the grid needs it most. And certain types of hydro
plants can rev up from low power to full capacity within seconds.
"There remains tremendous untapped potential in North America," says
Don Erpenbeck, a vice president at MWH, a global hydropower
construction and engineering firm in Broomfield, Colo. "After decades
of delay, we are starting to realize that potential."
But Mr. Erpenbeck adds that years-long waits for federal permits and
high capital costs make hydropower a tough sell to some utilities and
investors. Maximizing water energy in the U.S., he says, "is going to
take some guts."
Countries such as Brazil and China remain committed to large
hydroelectric dams and are forging ahead with big projects. Yet they
are also looking at smaller solutions favored by environmentalists.
The International Hydropower Association estimates that North America
has developed nearly 70% of its available hydropower resources and
Europe 75%. But the group sees huge potential in South America, Asia
and especially Africa, where just 7% of resources have been developed.
Dam Smart
In the U.S., one strategy gaining popularity is to add power plants to
some of the 80,000 existing dams that don't have hydroelectric
capacity. Technological advances like turbines that are gentler on
fish and oxygen-injection systems that help balance aquatic ecosystems
have won favor even among some environmental groups.
In one such project, American Municipal Power Inc. is spending $2
billion to add power plants to three dams on the Ohio River and invest
in additional hydropower elsewhere.
The utility's CEO, Marc Gerken, says the new hydropower will cost more
initially than coal or natural gas. But after the construction costs
are paid off in 30 years, the utility will enjoy cheap power for
several decades because the fuel�the rushing river�is essentially free
and the plant is designed to run without much maintenance for 60 or 70
years. AMP, based in Columbus, Ohio, is a nonprofit corporation owned
and operated by municipal utilities in the six states the company
serves.
Other technologies are more speculative. A much-ballyhooed experiment
that involved suspending a turbine from a barge in the Mississippi
River didn't prove to be worth expanding. The turbine is generating
power, but Hydro Green Energy LLC, the Houston-based start-up that
developed the device, says it has moved on to more promising ventures.
"It's still a power-producing, money-making device," but the economics
don't support expansion, says Vice President Mark Stover.
Several companies are experimenting with "low-head" turbines that can
pull energy from relatively small volumes of water dropping as little
as five feet over natural or man-made falls. One such project,
launched by Natel Energy Inc. of Alameda, Calif., uses low-head
technology to extract energy from an Arizona irrigation canal.
Federal scientists say some of these approaches look promising but
need more study. "With these new technologies, nobody knows what their
environmental impacts might be," says Doug Hall, who manages the water-
energy program at the Department of Energy's Idaho National Laboratory.
Pump Action
A less-experimental technology, dating back more than a century, is
also gaining currency as a means to store energy and back up the grid:
pumped storage, the system used by the Mount Elbert hydro plant
outside Denver.
The plant, sitting on the jewel-like Twin Lakes and managed by the
Bureau of Reclamation, plays a key role in keeping lights on and air
conditioners humming across the West.
At night, when demand on the power grid is low, the Mount Elbert plant
sucks water from the lakes, sometimes using wind power to pump that
water up into a reservoir above the plant. The reservoir acts as a
liquid battery�a huge pool of potential energy.
As the day warms up and the grid shows signs of strain, workers begin
to release the water down a 470-foot drop, through devices that turn
the pent-up energy into usable electricity. The water eventually pours
back into the lakes, where it can be recycled into power again the
next evening.
Pumped storage is quite popular abroad; China has 2,200 projects under
construction, and India and Ukraine aren't far behind. An analysis by
MWH shows that countries as varied as Romania, Thailand, Switzerland,
South Africa and Italy are also moving heavily into pumped-storage
construction. The U.S. has lagged, but federal authorities saw a surge
in permit applications in 2008 and again so far this year.
"No new dams are being built," says Dave Sabo, a senior adviser with
the Bureau of Reclamation. But just about every other approach to
hydropower, he says, is being studied and tested intensively. Says Mr.
Sabo, "All this stuff is in play right now�pretty heavily."
Ms. Simon is a staff reporter in The Wall Street Journal's Dallas
bureau. She can be reached at stephanie.simon@wsj.com.
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