by Bruce Barcott with photographs by Jamey Stillings

From Boom Fall 2015, Vol 5, No 3

Can wildlife and big solar coexist?

In the cool of an autumn desert night, the photographer Jamey Stillings and I roll out of Las Vegas into the dark Mojave Desert. With the glitz of the Strip in our rearview, we follow Interstate 15 south across dry desert lakes and wide alluvial fans, through miles of scrub and sand. The road is lonely, just a few long-haul truckers and crapped-out gamblers limping home to L.A. It’s a quiet time for humans, but out there beyond the asphalt there’s action in the desert. Owls and coyotes are hunting. Bats are darting after moths. Cacti and creosote open their pores to drink in the air’s moisture. Now and then a sign marks a lonely outpost: Sloan, Jean, Primm, once-hopeful townsites that never matured into towns. About five miles past Primm, on the California side of the border, we turn onto a road leading into the faint outline of the Clark Mountains. Our headlights catch a sign: Ivanpah Solar Project.

Ivanpah is the largest concentrated solar power (CSP) installation in the world. It’s also one of the most controversial. The $2.2 billion project, which came online in January 2014, is capable of producing 392 megawatts, enough electricity to power 140,000 homes—or all of Pasadena—during peak demand. It’s one of a handful of new mega-plants—including the Topaz solar farm in San Luis Obispo County, the Desert Sunlight plant southeast of Joshua Tree National Park, and the Genesis Solar Energy Project in eastern Riverside County—that have turned California into the first state to generate more than 5 percent of its electricity from utility-scale solar. But Ivanpah has come under fire from conservationists concerned about its bird-frying capabilities, and from green-energy skeptics who accuse Ivanpah’s backers of under-delivering on what was promised.

It’s so dark that I can’t make out where we are. Before I realize it we’re among the heliostats, the 173,500 pairs of mirrors that reflect the sun onto Ivanpah’s three power towers. Each tower is 459 feet tall, four-fifths the height of the Washington Monument. The mirrors stand upright at night in what their keepers call “sleep position,” so that when you drive among them in the pre-dawn gloaming it’s tough to make them out, what with the hall-of-mirrors effect and all. Dark reflecting dark reflecting dark.

“It’s like an immense art installation,” I say to Jamey.

He nods.

Photograph by Jamey Stillings.

Jamey’s been documenting the creation of Ivanpah for years, so these mirror-made mirages are nothing new to him. But coming upon them with fresh eyes, I can’t help but think of the monoliths of Easter Island, and the light-and-sensory artwork of James Turrell. I can’t wait to see what happens when the sun comes up.

We pass through security and find our way to NRG’s control room, a spacious chamber with computer consoles, dozens of flat-screen monitors, and about ten engineers. At 5:45 a.m., the day crew takes over from the night staff, which has been doing maintenance and prep.

Dawn arrives. Out in the desert, nocturnal owls, rats, mice, and bats retreat to their burrows. They want nothing of the day’s blasting heat. The heliostats, controlled by computers, slowly rotate into position. The first faint light shines on the dark band of the power towers.

At 8:02 a.m., the first of Ivanpah’s three units comes online. It starts small, generating six megawatts. Then nine. Then eighteen. At 8:14, an engineer calls from across the room. “We’re synced!”

Solar power shoots down the line. In San Francisco, customers of PG&E check their email and brew their coffee with Ivanpah energy. In Los Angeles, Southern California Edison brightens traffic lights and gives air conditioners their hum with power from the sun.

For Ivanpah, this counts as a good day: a clear sky with two power towers humming. (The third was briefly offline for maintenance.) Many days, the shift operators aren’t so lucky. Ivanpah was expected to produce more than one million megawatt hours per year, but in its first eighteen months the plant recorded less than half that output. Power plants, regardless of fuel type, aren’t turnkey systems. They require a break-in period during which they run at reduced capacity as engineers work out the bugs. At Ivanpah, that break-in period coincided with an unusual stretch of cloudy days, further reducing its output. The plant’s ramp-up accelerated in early 2015—producing more than double the power of a year earlier—but that didn’t stop critics from pouncing. “High-Tech Solar Projects Fail to Deliver,” the Wall Street Journal declared, presenting Ivanpah as Exhibit A.

That typified the plant’s first year, during which Ivanpah took a pounding in the media. In 2014, the Associated Press moved a story that claimed the plant was “scorching” as many as twenty-eight thousand birds annually—a total that would have required a full-time shovel crew to remove the constant rain of carrion. The biologist who came up with that number later downplayed it as a “back-of-the envelope” estimate, but the damage was done.

Then there was the erosion of confidence in concentrated solar power itself. Between Ivanpah’s groundbreaking in 2010 and its start-up in 2014, the price of photovoltaic (PV) solar panels dropped by more than half. That encouraged thousands of homeowners to join the distributed power revolution, which lets them use rooftop PV panels to power their homes and feed green energy into the grid. Then in 2015, Congress decided to end many of solar power’s federal grants, loan guarantees, and tax breaks. Green energy now provides about 24 percent of California’s needs, and the state’s renewable energy portfolio standard requires that to reach 33 percent by 2020. But right now, utility-scale PV farms and rooftop solar look like better economic bets than CSPs such as Ivanpah. Things change quickly in this space. In 2014 the U.S. Department of Energy saw Ivanpah and similar plants ushering in a “CSP renaissance in America.” By late 2015, it was uncertain whether Ivanpah’s power towers would be among the first of their kind in America—or the last.

The Mojave is a deceptive place. The driest and smallest of North America’s four deserts—it could fit inside West Virginia—it encompasses an extreme range of topographies and temperatures. The gentle, snow-capped peak of Mount Charleston rises to nearly twelve thousand feet just west of Las Vegas. It’s as much a part of the Mojave as Death Valley, the lowest (282 feet below sea level) and hottest place in the United States. In outline, the Mojave is lumpy and misshapen, like a deerskin tossed over California’s meeting point with Nevada and Arizona.

The Mojave’s defining quality is the difficulty of sustaining life within it. Anyone who’s road tripped from Los Angeles to Las Vegas knows this landscape as the journey’s major crossing, a sandy sea that requires preparation, supplies, and good luck to reach the other side. “The Mojave is a big desert and a frightening one,” John Steinbeck once wrote. “It’s as though nature tested a man for endurance and constancy to prove whether he was good enough to get to California.”

Photograph by Jamey Stillings.

The animals and plants that survive here are finely adapted to do so. The jackrabbit’s paddle ears are lined with shallow blood vessels, which allow the air to cool its blood. Kangaroo rats seal their burrows to capture the precious moisture released when they breathe. Owls and vultures obtain water from the blood of their prey. The desert tortoise, which often digs its burrows under the shade and camouflage of creosote bushes, survives the harshest seasons of the Mojave by estivating: it gorges on cacti, grasses, and wildflowers during spring, then disappears into the cool darkness of its underground home and waits out the heat of summer.

Native Americans have lived in parts of the Mojave for at least ten thousand years, but the human presence has been sparse throughout most of the area’s human history. Until recently, our need for water limited human habitation to areas where it pooled and ran. The Mojave Indians congregated mostly along the spine of the Colorado River. The nomadic Chemehuevi people, whose traditional lands include the Ivanpah Valley, are known as “those who play with fish.” Human impacts were minimal until the arrival of miners and ranchers in the mid- to late 1800s. The Clark Mountains attracted swarms of grubstakers seeking silver, borax, copper, lead, tungsten, and fluorite. In the 1880s, the mining town of Ivanpah popped up about where the solar complex stands today. The town did a brisk trade: saloons, a butcher shop, hay yards, hotels, and a weekly newspaper. Around 1900, the minerals ran out, and so did the people. The town was abandoned and the desert reclaimed the space.

Just as the seemingly empty and forbidding Mojave actually pulses with life, a desert that can appear bereft of industry in truth supports—and sometimes suffers—quite a lot of it. Though the town of Ivanpah never returned, the mining industry still survives here. Just over the shoulder of Clark Mountain sits the open-pit Colosseum Mine, a gold strike that operated from the early 1980s until 1993. A few miles south of Ivanpah is one of America’s largest rare-earth element mines, which produce the metals used in smartphones, high-efficiency lightbulbs, and photovoltaic cells. Mining is no longer the major industry here, however. Today the area’s economic engine is power production.

Photograph by Jamey Stillings.

Just over the border in Primm is the Bighorn Generating Station, a 598-megawatt natural-gas power plant completed in 2004. Next to it is the Silver State North Solar Project, a 50-megawatt photovoltaic solar farm. When it opened in 2012, Silver State North became the first power-producing solar project on federal land. It’s expected to be followed in the next few years by Silver State South, a 250-megawatt sister project, and by the 300-megawatt Stateline Solar Farm Project, a PV farm tucked between I-15 and the Ivanpah heliostats. In a little more than a decade, the Ivanpah Valley has become one of the most concentrated centers of power production in the American West.

That could be a good thing or a bad thing. It depends on your perspective. In the United States we produce most of our energy—82 percent—by burning oil, coal, and natural gas. With every megawatt produced from those sources, more carbon dioxide escapes into the atmosphere, stoking global warming. Nuclear power is extremely difficult to finance, permit, and build new plants for. Only solar, wind, and geothermal have the potential to replace big chunks of our appetite for burning carbon.

But no energy source is perfect. Ramping up renewables requires real estate. Wind power only works in places with a consistent blow. Solar power needs acreage. You can’t stack mirrors or PV panels on top of one another. Some of that space exists on rooftops. But rooftop solar has its limitations. If every house and commercial building in America harvested energy, they’d meet only 60 percent of the nation’s electrical demand. We most likely need more conservation, rooftop PV, better efficiencies, and utility-scale wind and solar.

On the day Ivanpah opened, solar power accounted for only 0.4 percent of America’s electricity budget. “There is an enormous gap between what needs to get done and what is actually happening on the ground,” said John Woolard, then CEO of the firm that designed Ivanpah, BrightSource Energy, during the plant’s construction. “I don’t think people really have digested how far behind we are from a policy perspective and how bad the consequences are. On a global basis we have got to put one gigawatt of zero-carbon power online every single day between now and 2040 just to stabilize CO2 emissions.”

That means lots of land. Ivanpah’s heliostats range over roughly five-and-a-half square miles (thirty-five hundred acres) of publicly owned, federally managed desert landscape. That’s four times the size of New York City’s Central Park. The Silver State North PV farm covers about one square mile. Stateline will shade another two and a half square miles.

There’s no way around it. Those are significant chunks of prime Mojave wildlife habitat. And therein lies a dilemma for environmentalists. Back in 2009, local conservation groups raised the alarm about losing five and ahalf square miles of high-quality tortoise habitat to Ivanpah’s footprint. The desert tortoise, Gopherus agassizii, is a long-lived and emblematic Mojave Desert species. It’s been listed as threatened under the federal Endangered Species Act since 1980. In some areas, the desert tortoise population has decreased by as much as 90 percent in the past thirty years.2

And the Ivanpah Valley, by all accounts, is excellent desert tortoise habitat.

That forced a number of environmental advocates, who usually champion solar, to take a critical look at Ivanpah. Solar power “should go on rooftops or in appropriate places, not the pristine desert,” April Sall, director of the Wildlands Conservancy, told Bloomberg Businessweek in 2012. “We need to tackle warming, but not forget there are other things at stake.”3

Local chapters of the Sierra Club found themselves divided on the issue. Some favored Ivanpah for its carbon-free energy; others thought the wildlife costs were too high. After the power plant’s partners agreed to significant tortoise mitigation measures—including buying seven thousand acres of private land to set aside as protected habitat, and keeping a permanent biology staff on site at Ivanpah—the national Sierra Club gave the project its blessing.

At midday, Jamey and I drive into the heliostat field with Len Cigainero, NRG operations manager. We stop at the boundary between the inner and outer rings of mirrors that bounce sunlight onto the boiler of Tower 2. “The inner ring is cleared and graded,” Cigainero explains. “Beyond that it’s left in as natural a state as possible.” Jamey and I wander amid the concentric circles. Each heliostat contains two garage-door-size mirrors. “There’s nothing that special about them,” Cigainero tells me. “They’re mirrors just like you have in your bathroom.” Except much, much bigger.

Photograph by Jamey Stillings.

As the day’s heat reaches its peak, Cigainero leads Jamey and me into a crude elevator that hoists us 376 feet—about thirty-seven stories—up Tower 2. It’s an awesome sight, standing at the rail, looking out at the mirror field: 120,000 brilliant white cards, all pointed in our direction. I imagine it’s something like Jimi Hendrix saw at Woodstock. Above us, the 800-degree heat generated by the focused solar energy of sixty thousand heliostats is creating superheated steam that cranks a power-producing turbine. All I feel is the warm day and a light breeze. The mirrors are so precisely focused on the boiler that nothing outside their flux zone feels the heat. But within that zone, birds and insects get scorched. If you watch the sky for a while, you’ll see little flares now and then, a visual record of birds and bugs flying too close to the flux.

Wildlife advocates raised early concerns about the effect of Ivanpah’s solar flux field on passing birds. Solar flux is a measure of the light energy in a given area. Ivanpah’s solar flux field encompasses the airspace between the mirrors and the tower boilers. The heliostats don’t create superheated air. Air absorbs very little light energy. Any object placed in the solar flux field, though, will absorb light energy and convert it to thermal energy. It’s the reason you can breathe the air in a car that’s been sitting in the hot sun, but can’t touch the steering wheel. Therein lies the risk to birds. If they fly through the flux field, they can singe their feathers and even catch fire.

It’s an enormous issue, for both Ivanpah and the future of concentrated solar power. Concern over bird mortality has stunted the growth of wind power, and singed wings could do the same to CSP. To ground truth the matter, the plant’s operators hired a team of biologists to record bird sightings and bird deaths for one full year. During my visit, I watched biologists use bird dogs to search the tower and heliostat areas, finding and recording avian carcasses. Meanwhile, engineers such as Cigainero are trying new solutions, including sound deterrents (sudden loud noises) and a scent derived from grapes that’s obnoxious to birds (smells like grape juice). From October 2013 to October 2014, biologists estimated that 1,492 birds were killed by the power tower and heliostats, through heat flux and collisions. A further 2,012 birds were killed by causes other than the solar power plant, and may represent something close to the area’s natural background avian mortality—birds killed by predation and disease. That’s nowhere near the alarming 22,000 number. But it’s still significant.

Photograph by Jamey Stillings.

Ultimately, Ivanpah’s bird issue comes down to a question of relative harm. The number of birds lost to solar flux pales in comparison to those killed in the United States by windows (an estimated 97 million) and domestic cats (110 million). But that comparison only gets us so far. It’s more useful to measure concentrated solar plants such as Ivanpah against other forms of power generation in a watt-by-watt comparison. Benjamin Sovacool, a Vermont Law School professor and energy policy analyst, has done just that. Sovacool looked at a wide range of data, from bird collisions with nuclear cooling towers, to wind-turbine mortality, to the effects of mercury poisoning and acid rain. The estimates were astonishing. Fossil fuel power plants (coal, oil, natural gas) were responsible, directly and indirectly, for 9.4 bird deaths per gigawatt hour (GWh) of power produced. Nuclear facilities were responsible for 0.6 avian fatalities per GWh. Wind turbines, which have become notorious for their bird damage, turned out in fact to be the most bird friendly of the compared power sources. Sovacool estimated that the blades and towers were responsible for 0.3 avian mortalities per GWh.4

Sovacool didn’t include concentrated solar power in his calculations. The technology was too new and the data simply didn’t exist. But if we use some crude calculations based on an early, small sample size, Ivanpah’s avian mortality lands somewhere in the wind turbine and nuclear power range. Ivanpah is expected to produce somewhere in the neighborhood of 1,000 GWh of power in a year. If all bird deaths are counted, that means the plant would be responsible for 0.6 avian fatalities per GWh; if only solar flux losses are counted, the figure comes down to 0.1.

Concern for bird fatalities at concentrated solar power plants seems to be a classic example of what we might call the fallacy of visible harm. We see a bird with singed wings and are moved, rightly, to call for more protection for these imperiled creatures. But what we don’t see are the millions of birds killed by the indirect forces—habitat loss, acid rain, mercury poisoning, climate change—perpetuated by our continued addiction to fossil fuels. The comparison isn’t even close: it’s a full order of magnitude. Coal-fired and gas-fired power plants kill more than ten times as many birds as wind and solar facilities combined. The difference is, those birds are dying hundreds of miles from the causes of their deaths.

As the sun makes its first move toward the horizon, we drive over to Ivanpah’s biological center, a modest collection of shipping-container offices and fenced tortoise habitats. This is Ivanpah’s desert tortoise biological center, a place they playfully call Desert Tortoise Head Start.

At Ivanpah, the desert tortoise acts as an umbrella species. The protocols taken to safeguard the reptiles and their habitat benefit a multitude of other species in the ecological web. NRG’s permit from the U.S. Bureau of Land Management allows them just nine desert tortoise “takings”—a euphemism for death—over Ivanpah’s planned thirty-year lifespan. They’ve already had one. “A biologist ran over a tortoise when doing a tortoise check,” Cigainero told me earlier that morning. “The tortoises look for shade, and this one found it under the wheel of his parked truck.” Ever since then, everybody on site does a vehicle perimeter check before starting up. It’s not just direct hazards that Ivanpah workers have to watch out for. There are indirect dangers, too. “We’re very careful about trash,” Cigainero told me. Desert tortoises have a coterie of predators: ravens, kit foxes, coyotes, red-tailed hawks, golden eagles, badgers, and burrowing owls. A spilled Coke or a misplaced Carl’s Jr. bag might be enough to draw these predators—especially ravens—to the site. And then their sharp eyes might spot a tasty tortoise.

At the biological station, I meet up with Max Havelka, a biologist who oversees the juvenile tortoise pens. The heat of the day has come up, and he’s decked out in full desert work wear: a wide-brimmed straw hat, extra-dark sunglasses, and a slathering of sunscreen. He tells me about the tortoise relocation operation.

“This turned out to be better tortoise habitat than anyone imagined,” he says. In the fall of 2010, before Bechtel broke ground on construction, a team of biologists scoured the Ivanpah site. Fall is typically an active time for tortoises, who emerge from their long summer burrowing to graze in the cooler autumn temperatures. The biologists gathered 173 adult and juvenile tortoises and relocated them to temporary holding pens in a 433-acre preserve set aside for rare plants and wildlife. “We started with sixteen tortoise pens, and ended up with more than a hundred,” Havelka tells me.

Photograph by Jamey Stillings.

Tortoises have a slow and precarious reproductive cycle. They can take up to twenty years to reach sexual maturity, and females lay eggs only when environmental conditions are optimal. Most hatchlings don’t survive. Researchers estimate that up to 98 percent of juvenile tortoises are killed by predators in their first years of life. That makes what happened after the tortoise-gather all the more curious and remarkable. Female tortoises in Ivanpah’s temporary holding pens began laying eggs left and right. Maybe it was coincidental. Maybe it was a response to stress. Maybe the females looked around at the plentiful forage, water, and predator protection, and thought, optimal conditions! Havelka and other biologists don’t know for sure. What they do know is that by the spring of 2011 they had fifty-three new juveniles on their hands.

After fitting the adult tortoises with tiny transponders, Havelka and his colleagues released them back into the Ivanpah Valley, outside the heliostat fields. The transponders allow NRG’s staff biologists to locate the reptiles and check on their health twice a year. To release the juveniles, though, would be to lose 98 percent of the next generation of a federally threatened species. So Havelka and the Desert Tortoise Head Start crew continue to nurture them behind protective fencing.

“We’ll keep them here until their carapaces”—their upper shells—”reach twelve centimeters in length,” Havelka explains. That’s about long as a Pepsi can is tall, and takes about five years. “At that point they’re able to fend for themselves.”

Photograph by Jamey Stillings.

As we stroll through the Head Start center, it’s tough to spot any tortoises. And yet we’re surrounded by dozens of them. “There’s one,” Havelka says. A four-inch juvenile crawls glacially under the shade of a creosote bush. Desert tortoises live up to 95 percent of their lives underground, and when they do emerge they exhibit no darting movements, as these would alert predators to their presence. Rule of survival: you don’t eat what you can’t see.

Photograph by Jamey Stillings.

Like a lot of conservationists, Havelka is aware of the tough trade-offs involved in a project such as Ivanpah. He sees the gains and losses every day. The Mojave, he says, “is amazing. It’s like a desert version of an old-growth forest.” It’s an apt description. The Mojave’s creosote bushes can thrive for centuries. They’re drought hardy and so oily that herbivores don’t touch them. King Clone, a Mojave Desert creosote bush ring, is believed to be one of the oldest living organisms on Earth. UC Riverside botanist Frank Vasek, who discovered the bush in the late 1970s, estimates the plant’s age at around 11,700 years.5

Desert tortoises in the wild can survive for fifty years or more. Their survival into the next century may depend on whether we can ramp up our renewable energy output—because they too are imperiled by climate change. Female tortoises lay fewer eggs during drought years, and soil temperatures affect the sex of embryos. Temperatures above 31.5 degrees C (88.7 degrees F) favor the development of females, so an increasing number of heat waves produced by climate change could leave the population here with a reproductive ratio problem. In other words, doing nothing is as risky to the long-term health of the desert tortoise as are the disturbances imposed by projects such as Ivanpah.

Late in the afternoon, we climb into a helicopter and rise thousands of feet above the desert floor. As the horizon pulls the sun closer, the Robinson R44 offers us yet another perspective on the Mojave. From sixty-five hundred feet up we can see over and beyond Clark Mountain and the Castle Range, the two mountain bands that define and drain into the Ivanpah Valley. The light’s low angle raises the contrast on the land. A multitude of dry creeks, washes, deer paths, jeep trails, rail lines, and dirt roads crosshatch and serpentine over the terrain.

At 5:11 p.m., all three Ivanpah power blocks glow an eerie white. They’re lit up like tall candles on a dining room table. Tiny movements ripple through the mirrors as the computer controlling the heliostats milks every last watt from the sinking sun.

Twenty minutes later, the shadow of Clark Mountain reaches out across the valley floor, nearly touching the outer ring of Unit 3’s heliostats. The darkness moves at a hiker’s pace, slow but steady. All three power blocks blaze until finally, at 5:56 p.m., Unit 1 and Unit 3 begin to fade.

The end of the solar day arrives quickly. Within two minutes the power block on Unit 3 is dark. Unit 2 still shines, but Unit 1 is fading fast. One minute later, Unit 1 is dark. By 6:03 p.m., all three tower boilers are black. Ivanpah is off the grid. One by one the heliostats move into sleep mode, standing vertically, reflecting darkness.

Meanwhile, in the desert, the nocturnal creatures start to emerge. As the intense heat of the day dissipates, they peek out of burrows, foxholes, and caves. Bats flutter into the evening sky. Tortoises crawl out of their holes to forage. The Mojave Desert stirs to life.

As we take one last swoop over the darkening valley, it strikes me that the Mojave has found, in the desert tortoise, its perfectly emblematic species: one that captures all the slow vigor, fragility, reticence, deception, indomitability, and strange beauty of the desert. Like the desert itself, its wonders and charms aren’t apparent upon first glance. But take some time to learn, understand, and appreciate. The same might be said of the Ivanpah project. It’s compelling and strange and not easily comprehended. But it may represent one of our best shots at getting right with the tortoise, the valley, the Mojave, the continent, and the planet. As the light fades, it seems a step in the right direction.


1. John Steinbeck, Travels with Charley (New York: Viking, 1962): 209.

2. Source: Defenders of Wildlife.

3. Quoted in Ken Wells, “Where Tortoises and Solar Power Don’t Mix,” Bloomberg Businessweek, October 10, 2012.

4. Benjamin K. Sovacool, “The Avian and Wildlife Costs of Fossil Fuels and Nuclear Power,” Journal of Environmental Sciences 9, no. 4 (December 2012): 255–78.

5. Frank C. Vasek, “Creosote Bush: Long-Lived Clones in the Mojave Desert,” American Journal of Botany 67, no. 2 (February 1980): 246–55.

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