The Race Is on to Build Big Power Lines, Clean Energy’s Missing Ingredient

Careful siting and thoughtful construction can make transmission lines less dangerous for birds, experts say.
Two sandhill cranes flying in front of out-of-focus transmission lines.

On a sunny September day in New Mexico, officials celebrated what developers call the country’s largest-ever renewable energy project. The groundbreaking for SunZia’s twin 550-mile electric transmission lines was a milestone in the national effort to bring more carbon-free power online. But the photo opp—17 years after the project was first ­proposed—indicated how challenging that transition will be.

To pursue his goal of a decarbonized electric grid by 2035, President Joe Biden signed legislation expected to cut emissions by 40 percent this decade. There’s a catch, though: Up to 200,000 more miles of high-­voltage transmission lines are needed to carry ­power from wind and solar farms to cities and towns. Developers must more than double the current rate of construction, or 80 percent of the Inflation Reduction Act’s emissions cuts will vanish, a Princeton University analysis warns. “Transmission is becoming the linchpin in the transition to a cleaner and more efficient electricity system,” says Jeffery Dennis, deputy director for transmission in the Grid Deployment Office at the U.S. Department of Energy.

Audubons Birds and Transmission Report, released

in August, argues that engaging developers early in the

PICTURING

process is key to rapidly building high-voltage power

PROGRESS

lines and minimizing ecological harm. The report also

identies prime bird habitat that overlaps with current

or future projects while promoting methods to alleviate

conicts with wildlife.

Supply and

Demand

Meeting the urgent

need for clean energy

will require increasing

the capacity to transmit

electricity—measured

here in terms of moving

1,000 GW-MILES

one gigawatt, or enough

EXISTING

EXISTING

NEEDED

to power 750,000

TRANSMISSION

87,000

58,000

homes, of power one

GW-MILES

GW-MILES

1,000 GW-MILES

mile—in nearly every

U.S. TOTAL

NEEDED BY 2035

region of the country.

PICTURING PROGRESS

Audubons Birds and Transmission Report, released

in August, argues that engaging developers early in

the process is key to rapidly building high-voltage

power lines and minimizing ecological harm. The

report also identifies prime bird habitat that overlaps

with current or future projects while promoting

methods to alleviate conflicts with wildlife.

1,000 GW-MILES

EXISTING

NEEDED

EXISTING TRANSMISSION

87,000

58,000

GW-MILES

GW-MILES

1,000 GW-MILES

NEEDED BY 2035

U.S. TOTAL

Supply and Demand

Meeting the urgent need for clean energy will require

increasing the capacity to transmit electricity

measured here in terms of moving one gigawatt, or

enough to power 750,000 homes, of power one mile

in nearly every region of the country.

The path to approval for transmission lines is often long, winding, and full of obstacles. SunZia, for example, was delayed by opposition to its original route, negotiations with private landowners, and reviews by federal, state, and local agencies. A recent industry report noted that, of 36 shovel-ready transmission projects, most were unlikely to break ground soon without policy changes.

The Biden administration is pushing reforms to speed the process. A rule proposed in August would make the Department of Energy a one-stop shop for federal transmission permits and require environmental reviews and other approvals to be completed within two years, twice as fast as the recent ­average. DOE also unveiled a $2.5 billion fund to finance projects, among other measures.

 

ROUTE PLANNING

LINE CONFIGURATION

Before

 

Building

To reduce collisions

with power lines,

 

developers can

avoid the highest-

 

risk areas, route new

 

lines alongside

existing ones (left),

and orient cables

horizontally rather

than vertically (right).

 

Before Building

 

To reduce collisions with power lines, developers

can avoid the highest-risk areas, route new lines

alongside existing ones (above), and orient cables

horizontally rather than vertically (below).

ROUTE PLANNING

LINE CONFIGURATION

Although climate change poses a dire threat to birds and other animals, environmental groups caution against sacrificing wildlife for the sake of building clean energy quickly. Collisions with transmission lines already kill as many as 57 million birds each year, a 2014 study found, and construction may involve felling trees and fragmenting habitat. “There needs to be a voice for birds at the transmission table,” says ­Garry George, Audubon’s senior director for climate strategy.

To provide one, George and his team partnered with Pattern Energy, which joined SunZia in 2018 and bought it in 2022. Urged by Audubon and others to make the project more bird-friendly, the developer changed its plan for crossing the Rio Grande, a route that posed a high collision risk to Sandhill Cranes. Pattern also agreed to follow an existing corridor through a national wildlife refuge, rather than build a new one, and to buy adjacent land for the refuge to manage. Ultraviolet lighting developed at Audubon’s Rowe Sanctuary will help birds see and avoid cables.

 

LINE MARKING

HABITAT MANAGEMENT

Available

 

Anytime

LIGHTS

Methods to make

power lines more

visible can reduce

 

FLIGHT DIVERTERS

bird strikes by up to

SINGLE LINE (SIDE VIEW)

 

90 percent (left),

 

while native plantings

can help rights-of-

10

m

way support species

MULTIPLE LINES (TOP-DOWN VIEW)

less prone to

collision (right).

 

FORAGE

BRUSHY

20

m

 

EDGE

AREA

 

Available Anytime

 

Methods to make power lines more visible can

reduce bird strikes by up to 90 percent (above),

while native plantings can help rights-of-way

support species less prone to collision (below).

LINE MARKING

LIGHTS

FLIGHT DIVERTERS

SINGLE LINE (SIDE VIEW)

10

m

MULTIPLE LINES (TOP-DOWN VIEW)

20

m

HABITAT MANAGEMENT

FORAGE

BRUSHY

 

 

EDGE

AREA

Not everyone is happy with the outcome. Some critics say it doesn’t go far enough to protect fragile habitat along the San Pedro River, for example. With so much at stake, there are no easy answers in the clean energy transition. SunZia may finally be under construction, but it’s just the start of a long road ahead.

This story originally ran in the Winter 2023 issue as “Power Struggle.” To receive our print magazine, become a member by making a donation today.