Stephen Robert Miller is an award-winning science journalist and author.
MAMMOTH, Arizona — Peter Else lives nearly off-grid in a house on the east bank of the San Pedro River in southeast Arizona. On a late-summer morning, his kitchen counters were strewn with yellow squash harvested from the organic garden outside. His water came from a massive drum of collected rain. His heat, when needed, radiated off a south-facing wall that harnesses the sun’s rays. By all accounts, Else is a bleeding-heart environmentalist walking the talk. So why is he vehemently fighting the largest renewable energy project in American history?
That project at issue is the SunZia transmission line, a 550-mile-long high-voltage power line that will carry some 3,000 megawatts of wind energy from central New Mexico to just south of Phoenix. The more than $8-billion joint wind farm and direct current (DC) transmission venture, owned by California-based Pattern Energy, has been touted as a critical weapon in the fight against climate change. The Biden administration has called it a “milestone” toward building the country’s clean energy grid.
Else might get behind it, too, if not for the proposed route. After entering Arizona north of the town of Bowie, SunZia would head southeast across the blistered desert and cut across the San Pedro Valley.
Else recognizes that the country desperately needs more renewable energy but argues that the San Pedro River is the last of its kind — the only undammed river in the Southwest — and that should count for something. “There is no legitimate reason for routing Pattern Energy’s 550-mile DC tie-line through 33 miles of the most remote and ecologically sensitive portion of the San Pedro watershed,” he said.
Here, in an overlooked corner of the Arizona desert, is a microcosm of the tradeoffs that line the path toward the renewable-powered future we so badly need.
The San Pedro River begins in northern Mexico, winds its way to the U.S. and joins the Gila River southeast of Phoenix. Its marshes, bosques and cottonwood groves provide a rare slice of Sonoran Desert riparian habitat, a corridor for jaguars crossing an international boundary, and a critical stopover for millions of migrating birds. Its unturned earth retains thousands of years of human history that hold immeasurable significance to the region’s Indigenous people. And it’s already under immense pressure.
Wearing a wide-brimmed hat and graying ponytail, Else carefully picked his way down a steep slope behind his house to the San Pedro’s bank. “This is the developing world,” he said, gesturing to the green-studded hills that rose along the river’s course. He meant that the roads are bad and the services limited in this overlooked corner of Arizona, but he was also alluding to a litany of hard-wearing land uses and construction proposals that have threatened it for decades. These include copper mines, a border wall, cattle grazing, an interstate highway and a housing development that would convert more than 12,100 acres of untrammeled riverside habitat into 28,000 residences, four golf courses and a resort.
He and a cadre of environmental groups had successfully stopped or stalled most of the proposed threats bearing down on the San Pedro Valley, but on Sept. 1, after nearly two decades spent securing permits and permissions, Pattern broke ground in Corona, New Mexico. SunZia was on its way at last.
Still, energy infrastructure must go somewhere. The San Pedro narrowly escaped the destruction of the Industrial Revolution, when the rush to develop coal and oil displaced Native people and laid waste to Western landscapes. How can we prevent the San Pedro and other ecologically sensitive areas like it from being overrun by this next round of energy development?
Wiring The Future
The Biden administration has set a goal of wiring a carbon-free energy grid by 2035, and wind is a key piece of the puzzle. Wind currently provides more than 9% of the country’s total electricity, which is enough to power about 40 million homes. More wind farms are in the pipeline, but all the wind in the world won’t account for much unless it can be transmitted from where it’s captured to where it’s needed, when it’s needed.
For now, the country runs on a system fragmented into three separate grids: the Eastern, the Western and Texas. Meeting President Joe Biden’s goal will require connecting them and stringing between 1,400 and 10,100 miles of new high-capacity lines per year, doubling or tripling the current transmission capacity, according to the National Renewable Energy Laboratory. This is where SunZia comes in.
The project begins in central New Mexico, where Pattern is constructing more than 900 wind turbines capable of generating 3,500 megawatts of electricity. The company promises that its work will create 2,000 jobs and generate more than $20 billion in total economic benefits. And it will bring reliable, comparatively clean energy that ramps up in the evening when solar power abates.
“We’re going to be providing enough clean energy, produced at the right times of the day, to power three million Americans’ needs,” Kevin Wetzel, Pattern’s lead developer for the SunZia project, told me. “It is a really meaningful step in the right direction for increasing reliability in the desert Southwest while simultaneously delivering clean energy to the areas that need it most.”
SunZia is a private venture, not a public utility. Its high-voltage direct current (HVDC) line will offer a one-way supply of energy from Pattern’s New Mexico wind farms to its customers, many of whom will be in California. Without using eminent domain to capture land for its right-of-way, the project has navigated a circuitous marathon of bureaucratic machinery over 17 years; the plodding process has made it the poster child for the bottlenecked reality of modern energy development.
Since 2006, SunZia has negotiated agreements with multiple state and federal agencies, including the U.S. Bureau of Land Management, which manages over 30% of the project route, as well as a sea of private landowners. In New Mexico, the original route was altered to bypass the White Sands Missile Range and again to avoid the Bosque del Apache National Wildlife Refuge. At one time, SunZia could have taken any of several potential paths across Arizona, and some of them would have avoided the San Pedro Valley. But the BLM scratched each alternative one by one for various reasons, until a singular option remained.
In 2015, when Arizona’s Power Plant and Transmission Line Siting Committee was called upon to sign off on the route, its chairman summed up the choice: “I think this is a perfect example of the … effort to find the least worst decision.” He added: “The path of least resistance is the pristine valley, the San Pedro River Valley.”
On Hallowed Middle Ground
No one doubts the San Pedro’s natural value. The National Audubon Society has long championed its extraordinary wealth of avian biodiversity. The Sierra Club, Nature Conservancy, Pima County and even a former SunZia project manager, have all acknowledged that the river’s north-south-trending corridor of green is an uncommonly wild asset that would be difficult to protect from developmental impacts.
Still, by the end of 2025, SunZia is expected to enter the valley north of Benson, Arizona and cut through it for 45 miles. During that stretch, the transmission line would be the only visible structure overland; its high-voltage cables strung from towers spaced every 1,400 feet, reaching 135 feet high. Beneath them, crews will clear a right-of-way through scrub and cottonwood. This strip of land immediately below and adjacent to the line transmission line will stretch anywhere from 400 to 1,000 feet across.
Pattern takes these environmental concerns seriously, Wetzel said. The company has promised to amend damaged habitat by replanting or replacing broken Saguaro cacti and constructing towers on hills where possible to avoid some clear-cutting. However, little can be done about future damage; accessing the area will require hundreds of miles of new roads that will remain afterward for maintenance and racing four-wheelers. Such future access poses a particular threat to sites in the valley that contain more than 12,000 years of human history.
There are pictographs, petroglyphs and unearthed tools, camps, irrigation canals, human remains and even the terraces of what had once likely been an ancient agave plantation. To the Apache, O’odham, Hopi and Zuni people, these aren’t just relics, they’re places of active communion with ancestral generations. Federal agents are required under the National Historical Preservation Act to catalog and protect them from modern activity.
The first step to keeping this type of project from becoming a problem is communicating with anyone who might have a problem with it. SunZia endured six years of environmental review and more meetings with private landowners than Wetzel can begin to remember, but somehow, Arizona’s tribes feel they have fallen through the cracks.
Last March, leaders of several Indigenous communities joined Else in asking that SunZia be rerouted. “All of the evidence for the significance of the San Pedro Valley Traditional Cultural Landscape to the Tohono O’odham Nation and other Tribes has been largely ignored by the Bureau of Land Management,” wrote Ned Norris Jr., the Tohono O’odham Nation chairman, in a complaint to the BLM.
Over the nearly two decades that SunZia has been in the works, the BLM had consulted with tribes, and Wetzel said Pattern maintained “a very good relationship with a large number of them.” But some tribal leaders contend that the BLM has not adequately cataloged the area’s cultural resources, and they say federal officials are not taking their complaints seriously. In January, leaders of the Tohono O’odham Nation and San Carlos Apache Tribe, together with Archaeology Southwest and the Center for Biological Diversity, sued the federal government to stop construction.
Clearly, there is momentum behind SunZia and similar projects underway across the country. Nudging this particular undertaking across the finish line has become a presidential priority, and the urgency to act has pushed powerful conservation groups into awkward corners. In August, Audubon Southwest, which had fought long and hard to protect the San Pedro’s bird bastions, changed its tune. Noting the lack of political will to achieve renewable energy goals by alternative means, it officially threw in its hat with SunZia.
“To get any project built, all sides are going to need to come to the middle,” Wetzel said. “You need a coalition of support that understands the tradeoffs of infrastructure development between trying to solve the climate crisis and the realities of developing infrastructure, which is physical; it has to exist somewhere.”
In September, the BLM gave the green light for SunZia to proceed, and by October, bulldozers had begun shaving away the valley’s greenery to expose red dirt roads.
Pattern Energy’s Wetzel maintains that its project’s current route is the most economically, environmentally and culturally responsible option. But Else, who has contended with SunZia since before Pattern took over ownership in July 2022, said there was a time when he had been hopeful the line would take an alternate route, traveling miles north of the San Pedro, where it could piggy-back on existing transmission infrastructure. This collocation of resources eliminates the need to cut a fresh right of way through the desert and offers a powerful solution to untangling the transmission knot in Arizona and beyond.
As an example, Else has pointed to the Southline Transmission Project, which is a 280-mile HVDC connection between El Paso and Tucson that has managed to secure all its major permits and is expected to begin construction in 2025. The privately owned line will enter Arizona near SunZia’s chosen route but, where possible, will use existing infrastructure, which Southline’s owners will update to accommodate high-voltage electricity. However, Southline’s path doesn’t reach pockets of New Mexico’s wind power as efficiently as SunZia would like theirs to.
As a general rule of thumb, transmission costs about a million dollars a mile, Mark Detsky, an attorney who specializes in energy practice, told me. If a line needs to make a turn, that comes at an additional cost. If it needs to climb a hill or span a gap, more cost. Renewable energy is also uniquely tied to geography. Wind generation must happen where the wind is, for instance, whereas a natural gas plant can be built just about anywhere. As a result, renewable transmission lines must often cover long distances between where energy is generated and the end user, but electricity loses voltage over extended stretches, so owners are woe to take the scenic route.
Another option that Else has pointed to for years is the High Plains Express. It has been around, as an idea, at least, as long as SunZia, and was also intended to carry wind energy from central New Mexico into Phoenix. Before it fizzled out, the proposed project would have parallelled SunZia’s route through New Mexico, entering Arizona on a northern path that avoids the San Pedro Valley. Whereas SunZia will create about 130 miles of new corridor through untouched areas, the High Plains Express path would not impact intact landscape.
It would seem pointless to endure all the regulatory, economic and political heartache needed to win approval for and construct a new pathway when companies can glom onto an existing one. But the reach of the country’s grid is limited, and experts say there aren’t enough existing miles of power lines to meet energy goals.
The BLM so far oversees nearly 17,000 rights-of-way for electric transmission across public lands in 11 western states and Alaska. “Each transmission line has a maximum limit of energy which it can carry. As new renewable energy projects are brought online, it is foreseeable that additional transmission lines will be needed to carry the increased energy production,” said Allison Sandoval, a spokesperson in the BLM’s New Mexico office.
Collocation with existing transmission lines can limit the challenges, but not erase them. It requires building another set of lines, which brings its own regulations and environmental impacts (albeit a fraction of what a brand-new right of way does). During construction, the existing line must most likely be taken offline. Engineers must also factor in the risks of running more than one transmission line on the same infrastructure. A wildfire blowing in could raze both lines at once, and a double line can bring security concerns, as it’s apparently a more attractive target for terrorism, according to the U.S. Government Accountability Office.
However, doubling up is worth the risk in the trickiest pinch points, like river crossings and jogs across fragile habitat. “Oversized capacity should be used where you only have one shot and a limited space to work,” Detsky said.
In those cases, he said, it makes good sense for transmission to be bunched together, even for a short stretch, to minimize impacts before splintering out on individual paths again. The San Pedro Valley would seem like just the pinch point to warrant such a move, but Pattern may have another incentive to stick with its chosen, problematic route: the simple fact that, well, it has gotten this far.
SunZia and the High Plains Express both popped up as ideas around 20 years ago, but SunZia is the only proposal still standing. In the years since the Public Utilities Regulatory Policies Act of 1978 sought to open power generation to more competition, utility companies have grown aggressively possessive of the nation’s energy grid.
“Transmission is the utilities’ ultimate fiefdom, because it’s not only service, but it’s also reliability. And it’s another backdoor way of controlling generation,” Detsky explained. To maintain their grip on this lucrative domain, American utilities have lobbied to keep the tables stacked against private energy development upstarts. These days, a utility-backed project can sail from idea to construction in nine years, Detsky said, while the same proposal from a private developer will linger in bureaucratic purgatory for decades.
SunZia is the survivor. And as long as the path to a renewable future remains mired in this hellish bog of overlapping state and federal agency protocol, industry will present sacrifices like the San Pedro as a prerequisite for progress.
Old Roads Made New Again
History and politics have left us with a tripartite energy grid comprised of fiefdoms that don’t play nicely and a landscape so striated with infrastructural scars that there hardly seems room for fresh wounds. And yet, one of the simplest solutions may be right in front of us.
Far north of the San Pedro Valley, in Minnesota, the NextGen Highways project has been rallying support around the idea of running renewable energy transmission along public roadways, giving second life to Eisenhower’s dream of strengthening the country by connecting it. The interstate highway system already links every corner of the country with wide rights of way paved through the most efficient routes. Using existing highways would cut out the chore of winning permission from countless private landowners and cut down on the litany of permitting needed to turn fresh dirt. NextGen would bury HVDC lines beside roads so that millions of Americans would soon find themselves speeding alongside renewably generated electrons. In a recent poll, three-quarters of Minnesotans liked the sound of that.
Another Midwestern experiment, called SOO Green, has taken a page from the country’s fiber optic playbook. It would apply that strategy along railways, rehabilitating the steel lanes that once paved the way for westward expansion. To start with, it envisions connecting two of the nation’s largest energy markets — the densely populated mid-Atlantic region and the Mississippi watershed — with a 350-mile underground HVDC cable.
“Rail is an opportunity to create unconventional alliances and assess common cause among people who would not necessarily be locking arms,” said Bill Moyer, an environmental activist in Washington state, who has spent the last decade pushing the idea of electrifying the nation’s railways. “This is critical national infrastructure, and it needs to exist not merely for capital to come and mine profit from it, but for a public purpose as well,” he said.
Moyer’s plan, which he calls Solutionary Rail, is something like SOO Green but goes beyond using railways to carry electricity — it would also use renewable electricity to power the trains. Rail freight’s greenhouse gas contribution is comparatively small (about 0.5% of the country’s total and about 1% of transportation’s emissions), but Moyer hopes that investing in electrified rail would divert some cargo off of highway-bound freight trucks, which produce a third of the transportation sector’s emissions. Meanwhile, electrifying railyards would clean up what have become toxic hazards to rail workers and people living around them.
And it would make renewable energy available to the towns along the trains’ routes. This, Moyer hopes, would help to revitalize rural communities that were left behind when the nation veered from investment in railways to highways. With railroads as the backbone of a far-reaching electric network, cities and small towns could tap from and add to the grid with whatever form of renewable generation they happen to have on hand. Democratizing the energy system in this way offers an about-face from the days of plowing through the West’s land and communities to fuel Eastern industrial shareholder profits.
It’s a moonshot if ever there was one. But Moyer has built a coalition around the effort that includes high-ranking energy experts, politicians, tree huggers and railway workers. He’s published white papers and books, presented to members of Congress and federal agencies, all to lay the groundwork for an idea whose Achilles’ heel may be its ambition: The scope of Solutionary Rail would be more at home in the era that built the railroads than the one now underutilizing them.
This vision of using existing rail to do more than simply produce profit from another source of energy gets to one of Else’s key complaints about SunZia in southeastern Arizona.
The wires that Pattern Energy is unspooling across the San Pedro are intended to carry direct-current power in one direction, from the company’s wind farms to its customers. An earlier version of the project also included a parallel line that would carry alternating-current electricity — the kind that would allow someone with a solar-powered house to be a contributing member of the grid. But as SunZia dragged on, that option got left on the cutting room floor.
Still, to many, SunZia will no doubt mark a massive victory for renewable energy when it is completed. And organizations like Audubon Southwest say it already represents a win for an environmental movement that must find ways of working with the energy industry. There will be more transmission projects — thankfully — and some of them will chart courses across vast swaths of the country, linking cities and towns with distant wind farms, solar fields and geothermal hot spots. SunZia is paving the way for them; that is a remarkable achievement.
But if the price is marring the rare habitat and irreplaceable cultural heritage of a place like the San Pedro, the course it is plotting risks dodging an opportunity for true innovation in favor of forging ahead with simply a shift from one form of energy to another within the same extractive system.
For his part, Else intends to keep pushing for something more. “We’re not interested in win-win situations with corporations when the ecosystem loses,” he said.