The Washington Post - USA (2022-05-24)

E6 EZ EE THE WASHINGTON POST.TUESDAY, MAY 24 , 2022

emitters of methane. It just

doesn’t stand to reason.”

The addition of hydropower to

nonpowered dams can be finan-

cially attractive to developers.

Typically the dam’s operation is

said LeRoy Coleman, director of

communications for the National

Hydropower Association. “So,

from our perspective, it’s inaccu-

rate to label hydropower, particu-

larly nonpowered dams, as major

and reservoirs have serious meth-

ane emission problems.

“Every single water body from

a marsh, to a wetland, to a lake

omit a certain amount of meth-

ane. It’s just a natural process,”

and agriculture. It naturally

emits from bodies of water as a

result of the decomposition of

organic matter. Those who favor

hydroelectric power strongly dis-

agree that America’s older dams

not changed, so there is usually

much less opposition from com-

munities and environmental

groups than there would be to a

new dam project.

Both sides agree that the meth-

ane issue needs more study and

that the exact science on methane

emissions from hydroelectric

power is not yet settled.

“The jury is still out on whether

reservoirs emit more methane

than natural lakes,” wrote Bridget

Deemer, a research ecologist with

the U.S. Geological Survey, in an

email.

Deemer added that a 2016

study she was the lead author on

found that reservoirs emit more

than previously estimated. “How-

ever, more recent work indicates

that lakes and reservoirs may be

pretty similar. The exciting thing

is that reservoir ecosystems are

highly managed to begin with so

managers have an opportunity to

adjust [reservoir] operations

based on what the data shows.”

Many of the nonpowered dam

projects being developed are run-

of-the-river hydroelectric sys-

tems. Instead of using reservoirs,

these projects typically rely on

the natural flow of the river to

spin a turbine and generate pow-

er, so their methane emissions

would most likely be very limited.

Rye Development is a leading

developer of run-of-the-river

dams and has 22 licensed hydro-

power projects in its pipeline.

The scale of these projects var-

ies.

The smallest is Kentucky Lock

and Dam 11 on the Kentucky

River. This hydropower conver-

sion makes use of a lock and dam

system developed by the Army

Corps of Engineers. The lock and

dam now belong to the state of

Kentucky, which maintains the

system to provide drinking water

and is thus critical infrastructure.

When completed later this year,

the project will produce

18,500 megawatt hours annually,

enough energy to power 1,700

homes.

Rye’s largest retrofitting proj-

ect is the Overton Project on the

Red River in Louisiana. It is a

49 megawatt project that when

finished will provide enough elec-

tricity to power more than 9,000

homes.

“We see an opportunity for

hydropower that really is going to

have a limited impact on the

environment,” said Paul Jacob,

Rye’s chief executive. “That for us

dictates where we go; we start out

looking for dams that are there

for an essential purpose. By and

large, those are navigation dams

or dams that are on flood control

properties, and most of those

projects are maintained and

owned by the Army Corps of

Engineers.”

Jacob said that Rye tends to

develop sites that are close to

each other and affect the same

watershed. Having small hydro-

power plants close to each other

can allow communities to operate

their own microgrids, a concept

increasing in popularity because

it can lend a local grid resiliency

in times of crisis or power outage.

“This is a resource where infra-

structure is already built, the

dams are still being maintained,

and they are not going away,”

Jacob said. “So why not capture

that energy and use it? Other-

wise, you know, it’s a wasted

resource.”

forecast that hydropower in the
United States could expand from
its current capacity of 101 giga-
watts to nearly 150 gigawatts by

2050. This growth would come
      not from new dam construction
      but from upgrading existing hy-
      droelectric resources, adding
      pumped storage capacity, and ret-
      rofitting nonpowered dams for
      hydropower.
      Most American dams are more
      than 60 years old, and many have
      outlived their utility or present
      public safety risks. A consensus
      exists between the hydroelectric
      industry and environmentalists
      that these dams should be re-
      moved. But hydroelectric compa-
      nies also like to tap into the
      energy-producing potential of
      the nonpowered dams that re-
      main essential to our infrastruc-
      ture.
      “There are a lot of dams that
      are on the landscape that aren’t
      serving a purpose and wouldn’t
      be economic generators were you
      to add hydropower to them.
      Those dams need to be removed,”
      said Kelly Catlett, the hydropow-
      er reform program director for
      American Rivers, a nonprofit
      group focused on protecting and
      restoring rivers and riparian eco-
      systems. “But where you have a
      dam that is serving another pur-
      pose and it’s going to be around
      for a while, why not put hydro-
      power generation on it?”
      Nonpowered dams compose
      the vast majority of America’s
      dam infrastructure. They can be
      found across the country, come in
      all sizes and were built to address
      a wide array of needs, including
      flood control, navigation, water
      supply and recreation. Out of the
      estimated 90,000 dams in the
      United States, about 2,200 of
      them generate hydroelectric
      power. These hydropower re-
      sources, however, account for
      7 percent of national energy pro-
      duction and contribute 37 per-
      cent of the nation’s renewable
      energy supply.
      Hydropower interests and
      their supporters stress that hy-
      dropower could play a crucial and
      potentially unique role in energy
      production. Solar and wind pro-
      duce energy intermittently, but
      hydropower can operate 24/7.
      Some hydropower facilities can
      shut down or ramp up energy
      production quickly, providing en-
      ergy grids with stopgap flexibility
      during peak demand or in the
      case of blackouts.
      Environmental groups stress
      caution, however, noting that
      even existing nonpowered dams
      can produce environmental
      harm, such as blocking fish pas-
      sage and sediment transporta-
      tion and contributing to methane
      emissions.
      “We know that there are signif-
      icant methane emissions coming
      from reservoirs and that hydro-
      power operation can increase
      those emissions because of the
      operations of the project,” said
      Colleen McNally-Murphy, associ-
      ate national director for the Hy-
      dropower Reform Coalition.
      “There is a role for hydropower in
      this country’s energy portfolio
      moving forward, but it’s impor-
      tant to recognize that there are
      trade-offs there, as well.”
      Methane, a powerful green-
      house gas, is emitted by fossil fuel
      production as well as by livestock

DAMS FROM E1

RICK BOWMER/ASSOCIATED PRESS

Aiming to retrofit old dams: ‘Why

not capture that energy and use it?’

ROB SCHUMACHER/ARIZONA REPUBLIC/ASSOCIATED PRESS

Lake Powell, top, an artificial reservoir on the Colorado River, was created by the flooding of Glen Canyon by the Glen Canyon

Dam, above. There is growing interest to upgrade old dams in the United States to generate more energy.

RYE DEVELOPMENT

The Kentucky River Lock and Dam 11, which Rye Development plans to electrify. The company is a leading developer of run-of-the-

river dams and has 22 licensed hydropower projects in its pipeline.