The Long, Strange Success Story of America’s Biggest Clean Energy Project

Two years ago, John Podesta met with Jennifer Granholm, the U.S. Secretary of Energy. Podesta, a longtime Democratic aide, had just started a new role in the Biden administration, overseeing the Inflation Reduction Act’s implementation, and he was going to meet with Granholm about high-priority clean electricity infrastructure.

First on the agenda was a list of transmission projects to ferry electricity from wind and solar farms to cities and suburbs where it would actually be used.

“Up pops the list,” Podesta told me later. The first project was a line called SunZia.

“My jaw dropped,” he said. “I thought we solved that in 2014!”

No, no, Granholm said. There had been twists and turns. But now it was back.

If you want to understand why the United States can’t build infrastructure, look at SunZia.

Envisioned as a roughly 550-mile high-voltage transmission line connecting a sprawling 900-turbine wind farm in central New Mexico to the growing cities of Arizona and California, SunZia is — according to its developer — one of the largest electricity projects in American history. When it’s finished, the line will deliver 4,500 megawatts of electricity to consumers. Only two power plants nationwide produce more: the Grand Coulee Dam in Washington, and the Vogtle nuclear power plant in Georgia.

“It’s the largest clean energy project in America, and I think the largest clean energy project in the Americas ,” Podesta told me. “It’s huge.”

For nearly two decades, SunZia has bounced through successive stages of regulatory review, financial restructuring, and litigation. It has been fought over, bought, sold, and at one point, forcibly relocated by the Department of Defense. Today, 18 years after it was first conceived, it is finally under construction. At least one outstanding lawsuit is contesting its right of way. If all goes according to the current plan, SunZia will begin to deliver power to consumers in 2026.

SunZia’s timeline would present an inconvenience — arguably an embarrassment — in any context. In this particular context, it could even invoke despair. “It’s a classic example of how we’ve gotten excellent at stopping things in America, and if we’re going to take the climate crisis seriously, we have to get excellent at building things in America,” Podesta said.

The stakes are far larger than electricity bills. The United States has pledged to reach net zero greenhouse gas emissions by 2050. Reaching that target will require tripling the size of America’s power grid in the next 26 years, according to Princeton University’s Net Zero America study. If America were to power its grid entirely with renewable energy — a feat that many experts doubt is possible — then it would need a grid five times as large as what it has now.

Even if that study (led by my podcast co-host , Jesse Jenkins) overstates the need for new transmission, the mechanics of renewables dictate that the country must hook up its existing grid to the places where the sun shines brightest and the wind blows hardest. The Desert Southwest — and New Mexico specifically — features some of America’s richest solar and wind resources. To decarbonize America, that energy must be harvested and transported from these largely unpopulated areas to the dense urban centers where people actually live.

That is easier said than done. Although transmission projects are unusually important for climate change, they are also unusually difficult to build, especially compared to fossil fuel infrastructure. Or, well, not difficult to build, exactly — it’s just a big power line, and we know how to put those up — but difficult to get permission to build. Ultimately, that permission is in the hands of the government. But when it comes to long, linear infrastructure projects like power lines, there isn’t really a single “government” to talk about it with in the first place.

To build a transmission line, a developer has to secure permission from every state, county, city, and property owner along the route. If any of them denies the project, poison-pills it with endless requirements, or even sits on an application, then the entire project stalls. (Building a natural gas pipeline, by contrast, requires getting permission only from a single federal agency.) Electricity utilities don’t usually like transmission lines because they erode their local monopoly over power generation and distribution. Those utilities have such great influence at the state and local level — through outright lobbying and by funding local Little League teams, churches, and more — that they can often convince politicians and regulators to slow down or block a line.

For these reasons and more, America’s rate of new transmission construction has plummeted over the past few decades. In this history of stasis, though, SunZia presents a special case. SunZia is such a high-profile project that its enormous delays have terrified the rest of its small industry. If SunZia was defeated nearly 20 years after it was first proposed, then it could render the field un-investable, one investor confided to me.

Yet for all the hand wringing, SunZia is a success story. It has now fought off its most credible lawsuits, meaning that it is likely to get built. Within two years, huge amounts of climate-friendly electricity could be coursing through the American desert.

Earlier this year, I went to Arizona to examine more closely why SunZia has been so difficult to build and what finally allowed it to move forward. I spoke to the SunZia’s developer and the environmentalists who support the project — as well as those who oppose it. The question I was trying to answer: What did it get right? If America is going to reach its climate goals, learning those lessons — and learning them well — is going to be crucial. When SunZia is completed and running at full blast, it will generate roughly 1% of the country’s electricity needs. After that, to fully decarbonize the electricity sector, we will need to run it all back 99 more times.

The saga of SunZia begins in the summer of 2006, when representatives from utilities, developers, and government agencies from across the Southwest gathered to discuss expanding the region’s power grid. After looking at energy and economic data, the group decided that Arizona and New Mexico needed a powerful new transmission line to connect the swelling populations in the west with New Mexico’s abundant wind and solar potential.

The Southwest Power Group, a Phoenix-based energy company that had attended the conference, soon put together an ownership team of four utilities and stepped in to lead the project. They christened the line “SunZia,” after the setting sun on Arizona’s flag and the sign of the Zia people on New Mexico’s flag .

In June 2008, Southwest Power Group applied to the Bureau of Land Management, or the BLM, the national agency tasked with managing federal lands, for the right to build a major new transmission line across the two states. “Local, state, and federal permitting efforts will begin immediately,” the coalition announced in an optimistic press release.

The first phase of SunZia was expected to initiate commercial operation by 2013, the developers added.

Back then, when a developer tried to build a transmission line, they had a strong but not definitive sense of the route — in part because the federal government could ask them to change it if needed. Under the National Environmental Policy Act, the government must study how infrastructure projects — or, really, any federal action — affect the environment, inviting input from local governments, environmental groups, and nearby Native American nations. (That law does not require the government to protect the environment in any substantive way; it simply requires that it consult everyone and study a project’s impact.)

Heatmap Illustration/Pattern Energy

Southwest Power Group knew that SunZia would begin in central New Mexico, southeast of Albuquerque, and that it would eventually connect to a large-scale renewable project there. (At the time, the vast wind farm hadn’t yet been planned.) Then it would proceed due west, passing below Albuquerque, before veering southwest and passing north of the White Sands Missile Range. After that, SunZia would turn west again, eventually crossing into Arizona. It would pass near Tucson, Arizona — the exact route was uncertain — before finally turning north again and terminating in a substation in Phoenix’s southeastern suburbs. From there, the existing grid could ferry electricity into Phoenix or further toward California.

This route presented many difficulties, but two river crossings dominated concerns over the project.

First, SunZia had to cross the Rio Grande. Although that river is best-known back East for forming the U.S.-Mexico border, it begins in the Colorado Rockies and flows in a southerly direction through New Mexico, bisecting the state. In other words, you cannot cross New Mexico without crossing the river.

The Rio Grande creates an environment in New Mexico unlike anywhere else in the United States: a high-desert wetlands, where hundreds of thousands of birds from across North America spend the winter. The BLM and the Southwest Power Group decided that SunZia would shoot through a small gap between two wildlife refuges — the Sevilleta National Wildlife Refuge to the north, and the Bosque Del Apache National Wildlife Refuge to the south — that had been formed to protect these birds.

Second, SunZia would have to pass near Tucson, Arizona by one of three routes, each of which required some kind of sacrifice. The first option involved running the line alongside an existing 345 kilovolt transmission line that passed to the city’s south and west. But the city and county opposed that route, and it required securing a permit to cross the Tohono O’odham Nation’s land, which the tribe refused to allow.

That left two remaining routes. One option ran near the center of Tucson, passing very close to overwhelmingly poor and Latino neighborhoods. This route raised “environmental justice” concerns, the BLM said, in that it forced poor people of color who already live alongside energy infrastructure to bear even greater environmental costs for it. The other choice was to run SunZia east of Tucson and through the beautiful San Pedro Valley, one of the most pristine desert ecosystems remaining in Arizona. Although vast swaths of that valley are privately owned, Native American relics and cultural sites dot its landscape.

Forced to choose between harming civil rights or damaging the environment, the BLM reluctantly chose the latter. But to blunt some of the damage to the valley, the bureau directed the developers to follow existing pipelines or transmission lines for more than 40% of its mileage. It also ordered SunZia to commission studies of archeological sites along the route’s path so they could be mitigated or avoided entirely. (SunZia would later adjust its route to avoid some of the most archaeologically sensitive sites.)

Studying these options took much longer than the Southwest Power Group had ever imagined. The Bureau of Land Management published its final environmental study on SunZia in June 2013 — the same year SunZia was once due to begin operation. Southwest Power Group was finally ready to start construction. Then the Pentagon stepped in.

Scarcely a month after SunZia’s course was finalized through New Mexico, the Pentagon filed a formal protest . The approved route passed way too close to the White Sands Missile Range, the complaint said, and the BLM had “not adequately analyzed the significant risks to national security” that would result from building it.

The White Sands Missile Range is the country’s largest military installation and is vital to New Mexico’s economy. By suggesting that SunZia might imperil the base’s activities, the Pentagon was at risk of killing the project. But something about that claim didn’t sit right with Senator Martin Heinrich, a first-term Democrat and former Albuquerque city councilman. Heinrich was an engineer by training, and his father had been a utility lineman, giving him at least some familiarity with how the power grid worked. Why did a big power line threaten the military base miles away? He asked MIT’s Lincoln Laboratory to investigate whether the line would damage the base as much as the Pentagon said.

Six months later, in March 2014, the study was completed. According to news stories at the time, the classified study found that SunZia would impair the base’s activities, but that its effects could be mitigated. After months of intense negotiations with the White House, the Pentagon, the Department of the Interior, and Senator Heinrich’s office, Southwest Power Group agreed to bury five miles of the power line — an expensive solution, but one that would allow the project to move forward.

By that point, however, SunZia had captured the public’s attention and polarized New Mexicans. The state’s Republicans gleefully undermined the project in the press. As the Obama administration prepared to approve the line, a Republican congressman and former oil company CEO intoned that SunZia would “permanently damage” national security.

“Greenlighting the completion of SunZia along the chosen route is a reckless rush to judgment without thorough examination,” the congressman, Steve Pearce, said. (The federal government had, by this point, been studying SunZia for seven years.) He worried too that the line would “potentially destroy ancient Pueblo sites.”

In 2015, the Obama administration finally approved SunZia’s route. After nearly a decade, Southwest Power Group had the federal government’s permission to build SunZia.

But that was only the first step: Now, the company had to secure state and local permits. That would prove even more confounding.

The truth is that New Mexico’s environmentalists had never been comfortable with what SunZia would mean for the state’s wildlife. They hated the Rio Grande crossing. They were particularly stressed about what the structure might mean for sandhill cranes , a regal and crimson-headed bird that migrates to New Mexico from as far away as Alaska and Siberia. Few sights are more treasured by the region’s birders than the vast flocks of cranes that form in the Bosque del Apache Wildlife Refuge each winter.

Birders imagined that SunZia’s towers and low-hanging wires could maim or kill the elegant cranes. If SunZia could bury the line to help White Sands Missile Range, people asked, why couldn’t they also bury it below the Rio Grande and save some birds? They whispered, too, that the line would transmit not wind-generated electricity as promised, but rather gas-fired electricity from a power plant owned by Southwest Power Group.

When Southwest Power Group applied for a state permit to cross the Rio Grande, the birders’ moment came. The developers were still finalizing construction details and didn’t seem to have a strong sense of where exactly the line would go. In 2018, New Mexico’s utility commission rejected the permit and asked the Southwest Power Group to come back with more information.

SunZia was flailing. Building the line had taken much longer than Southwest Power Group had ever envisioned. Burying the line, even for a few miles, had made it a much more costly project. Now environmentalists doubted that it would help fight climate change at all and were making increasingly expensive demands.

Then a new company came into the picture: Pattern Energy, a San Francisco-based energy developer partially owned by Canadian pension funds. Pattern promised to build a vast wind farm — comprising more than 900 turbines — at SunZia’s eastern end. It became the line’s “anchor tenant,” in the jargon of energy developers, and, more importantly, the project’s public face.

“They came in, and they were quite honestly pretty frustrated with the way that [the SunZia project] had approached community engagement and talking with environmental groups,” Jon Hayes, a wildlife biologist and the executive director of Audubon Southwest, told me. Up to that point, SunZia had been the story of an “industry just trying to push their lowest-cost alternative through sensitive areas,” he said.

But Pattern behaved differently. “Why it was a success is that Pattern acted and negotiated it in good faith with us,” Hayes said.

Pattern hired researchers to study how and where the cranes fly. It agreed to install infrared lights on SunZia’s towers as an “avian avoidance system” that will be visible to cranes and make the lines shimmer in the dark. It bought a nearby farm to create a sandhill crane reservation (the cranes also eat corn from the fields) and donated the water rights to local conservation organizations. When a coalition of environmentalists, including Audubon, asked it to study the benefits of burying SunZia, Pattern warned that doing so could permanently alter the project’s economics — but they studied it anyway. Burying the line would ultimately have been more disruptive than building lines, Hayes said.

Heinrich’s office continued its involvement in the negotiation and also helped move the process along. Environmental groups that had initially opposed the project switched their allegiance, Audubon Southwest included.

Pattern’s research led it to conclude that the line should be moved into Serivetta National Wildlife Refuge so it could be co-located with another transmission line. (Moving it inside the refuge would also, counterintuitively, avoid the largest bird populations.) When Pattern brought the new route to local environmentalists and the Audubon Society, the conservationists agreed. Pattern then took the extraordinary step of applying to the BLM for a new route through New Mexico. By adopting the new route, SunZia could also avoid the White Sands Missile Range entirely, avoiding the costly need to bury the line.

Cary Kottler, Pattern’s chief development officer, told me that the project’s pre-existing climate credentials incentivized it to find ways to make SunZia more environmentally sound. “I think we did figure out a way for environmental groups to support infrastructure, which has not always been the case in the past,” he said.

“Pattern being a company that was willing to have discussions with us in good faith — and that conversation happening before the re-permitting process — was, I think, really important,” Hayes agreed.

Heinrich echoed that thought in a statement. “I am especially proud of our work to engage local communities, conservation organizations, and other stakeholders to find pathways forward while securing strong economic and conservation benefits for New Mexico,” he told me. He also thanked the BLM, the U.S. Fish and Wildlife Service, and Pattern Energy, for their “hard work and collaborative approach.”

“I firmly believe that when we work together, we can build big things in this country,” the senator said. “SunZia will have a massive economic impact in New Mexico while bringing us one major step closer to meeting our climate goals and conserving wildlife habitat.”

In 2020, Pattern entered into a deal with New Mexico’s Renewable Electricity Transmission Authority, a state agency meant to encourage long-distance power lines. The deal allowed New Mexico to reap some of the benefits of owning SunZia, and it spared SunZia from some scrutiny under state permitting law. It had taken 14 years, but SunZia was finally ready to build in New Mexico. It still had to tackle Arizona.

Pattern Energy bought SunZia outright from Southwest Power Group in 2021, and outside fundraising began to pile in. Last year, Pattern Energy announced that it had secured $11.5 billion in financing for the line, making SunZia the largest clean infrastructure project in dollar terms in American history.

But the line’s journey through Arizona — and specifically the San Pedro Valley — has remained controversial.

The San Pedro Valley. Robinson Meyer

Throughout last year, a coalition of environmental groups, local property owners, and two tribes — the Tohono O'odham Nation and the San Carlos Apache Tribe — pushed for the project to avoid the San Pedro Valley, alleging that the BLM had failed to study how SunZia would affect the landscape’s cultural value to Native Americans. In November, the BLM ordered Pattern Energy to pause construction on SunZia so that it could consult with the tribes again; the groups held a series of meetings in the fall.

But the tribes deemed that effort insufficient. In January, the Tohono O'odham and San Carlos Apache Tribe, along with the Center for Biological Diversity and Archaeology Southwest, sued BLM, alleging that it had not studied how SunZia would erode the valley’s cultural value.

Their argument turned on the interplay of two federal laws: NEPA, the law that governs the federal permitting process; and the National Historic Preservation Act, which says that the government must evaluate how its actions will affect archeological sites and Native American cultural sites.

If an infrastructure project will destroy an archeological or cultural site, the National Historic Preservation Act says that the government must mitigate that harm, mapping the relics and preserving what it can from them. Pattern and the BLM say that they have followed this law. After mapping and mitigating archaeological sites along its route, they agreed to move the line to avoid some of the most sensitive areas.

But the tribes argue that the entire San Pedro Valley is a sensitive cultural area. The Tohono O’odham Nation has argued in court and in the press that SunZia abuses its cultural property not by destroying any one cultural site, but rather by entering the San Pedro Valley in the first place. In essence, the tribe is claiming that the entire valley is a cultural site unto itself.

They say that the BLM must do what’s called a “cultural landscape” study, investigating not only discrete archeological sites along the route but the cultural value of the San Pedro Valley as a whole. “The tribes have been trying to say that this [valley] has central cultural and religious importance,” Robin Silver, an Arizona resident and the cofounder of the Center for Biological Diversity, told me.

Their argument was legally daring. The federal government approved SunZia’s route through the San Pedro Valley under NEPA in 2015, meaning that the six-year statute of limitations for that decision had already expired. But the National Historic Preservation Act process only wrapped up last year. The tribes and the environmental groups argue that if that law’s process had been correctly followed, then the BLM would have been forced to change SunZia’s route — even though doing so would essentially re-open the NEPA process.

“Pattern Energy and the Bureau of Land Management, all they do is hire consultants that confuse hard archaeology with anthropology. So they go out and dig in front of the bulldozers and say everything’s fine,” Silver said. “The fact of the landforms having significant cultural and religious importance has been here as long as the tribes have been here. It’s just that when Manifest Destiny became the rule of law, tribal concerns were blown off, and they’re still being blown off.”

The coalition’s argument also raised the specter of old trade-offs — trade-offs that the tribe, by focusing on procedural and cultural matters, did not address in its lawsuit. The San Pedro Valley is incredibly beautiful, for instance, but it is not completely pristine: It is already home to a large natural gas pipeline and a few smaller transmission lines. When I asked Silver why the pipeline did not destroy the valley, but the transmission line did, he said in essence that the pipeline did not have the same visual impact as SunZia.

“There are no 200-foot large power lines going through the San Pedro Valley,” he said. “The gas pipeline doesn’t have 200 foot towers.”

I pointed out that this suggested fossil fuel projects would never face the same scrutiny as transmission lines. “We need to figure out a way to connect the sources of our new energy to the users, and our grid is woefully archaic. No argument,” he added. “But we don’t need to go up every single valley, we don’t need to sacrifice everything else, because of this mantra of climate change.”

Yet there is no way to upgrade the grid without building large transmission towers somewhere . Silver suggested that the line could be shifted back toward Tucson, but that would seemingly place it back into the low-income, majority-Latino neighborhoods that BLM had hoped to avoid in the first place. The other available route would be to run SunZia west of Tucson, but that would force the line onto Tohono O’odham Nation land. When I asked a tribal spokesperson if the tribe had lifted its decade-old ban on SunZia crossing its land, he didn’t respond.

In fact, the Tohono O’odham Nation has not responded to multiple emails and calls requesting comment beginning in March.

Two weeks ago, a district court judge in Arizona tossed the tribe’s lawsuit. She said that the statute of limitations had expired and SunZia’s route could no longer be altered. While BLM had once suggested that it would do a cultural landscape study on the San Pedro Valley, it did not do so in a way that would change its obligation to the tribes, she ruled. Silver told me that the coalition will appeal.

SunZia hasn’t made it out of the desert yet. It still has to clear at least one remaining legal challenge, a lawsuit brought by the Center for Biological Diversity and its allies in Arizona state court. But with the federal lawsuit against it dismissed last month, SunZia now seems more likely than ever to become complete, making it a key piece of American zero-carbon infrastructure.

Which raises the inevitable question: Could SunZia have succeeded more quickly? SunZia required no fundamental technological leaps or engineering miracles; we have known how to build a power line of its size and length for years. Yet just the permitting has taken nearly two decades. If we finally get SunZia in 2026, that means that we could have had it in 2016. And that means that we could have burned less natural gas to meet the country’s electricity needs, or at least enjoyed more energy, for lower prices, with less pollution. America’s ponderous approach to building infrastructure is often described as an economic problem. But climate change transforms that regulatory torpor into an environmental challenge. What can we learn from SunZia such that we never have to go through this again?

You can see SunZia — as many in New Mexico now do — as a lesson in different approaches to building big new infrastructure projects. Many interests across the Southwest were unhappy with SunZia’s initial route in 2013. But in New Mexico, the Pentagon’s formal protest to that route led — quite happily — to Pattern Energy, Audubon Southwest, and environmental advocates working out a better plan for everyone involved. In Arizona, meanwhile, the old plans never changed, the same contentiousness remained, and they ultimately gave rise to a lawsuit.

You could also see it as a lesson in political power. Silver, the Center for Biological Diversity cofounder, told me SunZia succeeded in New Mexico for one reason: “Martin Heinrich.” Speaking with a mix of resentment and respect, Silver said that Heinrich pushed for negotiations between environmentalists, clean energy advocates, tribes, and the Defense Department, eventually nudging those groups to arrive at a mutually agreeable outcome. In Arizona, Silver said, national and state-level leaders have not taken the same hands-on approach, so the process has been much more acrimonious.

There’s some truth to each of these views. To get large-scale infrastructure projects done, it clearly helps to have a federal chaperone — someone who can spur cities, states, tribes, and conservation groups toward a final and constructive conclusion. The Biden administration is playing that role now for some projects, although it lacks local credibility, and Congress has helped to standardize the process by creating a “Fast 41” process where the government can prod along stalled infrastructure efforts.

But there is also something substantively different in New Mexico — you could call it high trust, good will, or a solutions-oriented approach to problem solving. It certainly helped that Pattern Energy was willing to work in good faith with local environmental groups. But that only works if all the other key stakeholders, including environmentalists themselves, respond in kind. The current tangle of state, local, and federal laws that dictate infrastructure permitting do not encourage this kind of constructive engagement, pushing opponents instead toward prolonged and costly legal battles. These laws also fail to substantively protect the environment, guaranteeing only that a process gets followed — not that the environment gets protected.

For decades, developers and conservationists have attacked each other over every project and prepared to fight bitter court battles over every detail. Developers assumed that conservation groups were out to block them at every turn and shut down, even when members of the public asked worthy questions. Environmentalists, meanwhile, suspected that any developers would destroy the land if given the opportunity, whether they were putting in oil pipelines or transmission lines, and would accept no protest to the contrary.

SunZia’s story repeats this old, messy tradition, while also laying the model for a new one — one in which clean energy builders and environmental protectors work together to find the best solution for the environment and the climate. We will need many more success stories like it if America is to meet its climate goals — 99 more, to be exact.

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