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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.
Audubon’s 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
identifies prime bird habitat that overlaps with current
or future projects while promoting methods to alleviate
conflicts 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
Audubon’s 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.