The Pomona Freeway from Los Angeles to Chino Hills is pretty charmless. Lots of gas station signage and personal injury attorneys promising to “fight for you.” But the defining landmark is a web of 500-kilovolt power lines, the electrical lifeblood of a heavily air-conditioned region and an eyesore marring the California sunset.

As the L.A. sprawl has crept steadily eastward, such large-scale energy infrastructure projects have run into opposition from the communities in which they’re being built. Chino Hills is one such community. A quiet, picturesque exurb with breathtaking views of the San Gabriel Mountains, its rows of pristine hillside houses are a real estate agent’s dream. Part of the town’s appeal stems from its prime location astride Tres Hermanos Ranch, a swath of 2,450 acres of undeveloped wetlands and undulating hills. Tres Hermanos is part of one of the largest expanses of developable open space in a corridor covered in strip malls and subdivisions, an emerald island in a sea of gray and brown sprawl.

“This is real coastal sage scrub,” says Robin Smith, bending down to touch the crispy-looking bushes that rise to our ankles. Smith’s house is located just 200 feet from the boundary of this land, which she cherishes with zeal. “California native landscape is unique in the world,” she says. “That’s why back in the old days you had these legends of golden California, because it was really true.”

Tres Hermanos isn’t a public park. Though it’s located within the boundaries of Chino Hills and the neighboring town of Diamond Bar, those towns don’t actually own it. That’s because in the 1970s, Tres Hermanos was bought by City of Industry, another municipality located 20-odd miles west down the Pomona Freeway. Five years ago, the state of California took control of the land from Industry. On Aug. 24, it gave the city, its former owner, the green light to buy it back.

Why Industry wants a massive tract of far-flung empty land — and why some see its potential plans for the land as a case of the state’s environmentalist ideals run amok — is a story of Southern California sprawl and sustainability, of a region divided over how to protect the global environment while still preserving the local one. If the sale goes through for City of Industry (it’s currently under review by the state), Tres Hermanos could one day become a major generator of solar power, adding hundreds of clean energy megawatts to California’s electrical grid as the state races to meet the renewables goals set forth by legislators in Sacramento.

But critics of the solar idea see it as reckless overdevelopment, a shortsighted fix at best and, at worst, cynical profiteering amid a statewide renewables land rush. Which side you’re on depends largely on how you think the mistakes of the past should be remedied: by blitzing the region with clean energy development, or by safeguarding the scant natural space that remains.

California’s Solar Power Switch

Industry is a unique place. It is exactly what its name suggests: a workforce-oriented municipality that’s zoned over 90 percent industrial. Only about 200 people actually live there, but the city is home to 3,000 businesses, whose low-rise warehouses are backed up against the freight rail tracks that crisscross the city. Every day, 60,000 employees commute here to work in its distribution facilities, transiting imported goods from the ports of Long Beach and Los Angeles onward to the rest of the United States.

For years, Industry has been acquiring land near Chino Hills and Diamond Bar; for a time, the city was reportedly exploring the possibility of using the land to build a reservoir. When it bought Tres Hermanos in the 1970s, it transferred the land to its redevelopment agency, a post-war mechanism used by California cities to fund urban renewal. But in 2012, the state of California ordered all redevelopment agencies dissolved, and in doing so, effectively acquired any land that had been under those agencies’ control. Ever since then, Tres Hermanos Ranch has been under the auspices of the state, babysat by a seven-member oversight board that’s tasked with finding a suitable buyer for it.

Industry has taken the leading position to be that buyer. In August, the oversight board voted four to three to approve the sale of Tres Hermanos Ranch to City of Industry. The city paid nearly $42 million for the land and agreed to preserve it as open space for public use and public facilities. One such public facility that Industry is considering for Tres Hermanos is a large solar farm, the likes of which are proliferating throughout Southern California. Paul Philips, Industry’s city manager, declined to be interviewed for the story, but said in statement that “the city is looking forward to exploring options for the land dedicated to open space, recreational space such as hiking trails and exploring alternative energy projects that will help our region meet its sustainability goals.”

Industry’s pursuit of a proposal for a solar project was revealed in May by the Southern California News Group, a local media outlet exhaustively covering the saga. According to documents obtained by the reporters, such a facility could generate 440 megawatts of electricity — equivalent to 10 percent of the power consumed by Los Angeles. Against the backdrop of California’s effort to derive ever-increasing amounts of its power from renewable sources, the solar farm sounds like a big win for the environment.

The state’s green energy goals have increased pressure on individual communities to set aside their localist concerns for the sake of helping the state achieve its benchmarks. This is what concerns preservationists: a bureaucratic full-court press for “sustainability” that, in the process, runs roughshod over the natural resources the state already has.

This is why some of the strongest voices of opposition to a solar project are conservationists living in adjacent Diamond Bar and Chino Hills, who despair at the thought of decimating their natural idyll of riparian oak and freshwater emergent wetland with hundreds of acres of flat glass panels pointed at the sky. The oversight board approved the sale of the land to Industry after the city agreed not to use it for housing development. But this did little to assuage the concerns of advocates who want to protect the open space.

“Tres Hermanos is a big deal,” says Smith in Diamond Bar. She and Jim Gallagher, a Chino Hills resident, have emerged as vocal advocates for constraining development of the land. “We have eagles flying over us, and we just take it for granted.”

Gallagher and Smith are a mismatched pair in the grand cop-buddy tradition. Gallagher, dressed in by-the-book trousers and a button-down shirt, makes his points crisply and succinctly. Smith, ensconced in a flowing muumuu and a knit cap bedecked with flowers, is a gardener-harpist, and talks with the freeform flow of an eco-warrior slam poet. Gallagher ran for city council and is on a first-name basis with the local muckety-mucks, whereas Smith prefers to advocate from outside the system, which she says makes her want to take a shower.

But the two are simpatico on one point: They both see themselves as friends of the earth, which is why they don’t want a huge solar farm strafing the hills of Tres Hermanos Ranch. Their argument is basically this: While a field of solar panels may add green power to the grid, that doesn’t mean it’s the best choice for the environment. In the end, it’s still development.

“They [Industry] didn’t realize that solar is not going to be interpreted as being as environmental as they’d hoped, because it’s not that environmental,” says Smith. “It’s very, very dicey.”

Green Development vs. No Development

California is a solar energy juggernaut. The Solar Energy Industry Association ranks the state first in the nation for both its current market and its projected five-year growth. According to the nonprofit Solar Foundation, of the 260,000 people working in U.S. solar jobs in 2016, over 100,000 of them were employed in California.

This rapid growth is due to the state’s sunny climate, its powerful economy and its progressive politics — politics shared, in principle, by Gallagher and Smith. But the cognitive dissonance that separates Gallagher, Smith and the other advocates working to keep Tres Hermanos Ranch untouched comes down to conflicting baseline philosophies about what’s best for the planet: proactive environmental engineering, like a solar farm, or passive conservation — “green” development or no development at all.

One aspect of Smith and Gallagher’s argument against a solar farm is fairly familiar. They believe it could damage the very habitat it sits on, threatening the land’s vegetation and wildlife. “This coastal sage scrub looks brown and crunchy, but it’s not flammable,” says Smith. “The oak trees are drought tolerant. The vegetation acts as a natural sponge and buffer for the watershed.” They point out that Tres Hermanos is home to the burrowing owl, listed as a species of special concern by the state, and that it’s part of one of the world’s 36 biodiversity hotspots (though to be fair, that hotspot, the California Floristic Province, covers most of the state as well as parts of Oregon and Mexico.)

Similar arguments have been used to fight other renewable energy development projects — wind farms that “grind up the seabirds,” as Smith puts it, or hydropower plants that decimate fish stocks. But there’s another, more macro angle to their argument for keeping Tres Hermanos untouched: Smith’s assertion that “this area impacts the county, the state, the nation and over in the Bahamas.”

“The Bahamas” was a reference to Hurricane Irma, one of the superstorms that recently tore through the Caribbean 3,000 miles from our perch overlooking the ranch’s tan slopes. “We now live in a world where we know all this stuff is important,” says Smith. “The trees and vegetation contribute to climate stability.” Gallagher echoes this: “It’s like how the rainforests in the Amazon are critical to the whole planet.”

Here’s where local interests and regional goals begin to diverge, and where the question of what’s best for “the environment” — itself a hazy concept — gets even more subjective. If we were talking about covering Tres Hermanos in McMansions, it would be a no-brainer. But the idea on the table is a project that promises to pull a large portion of fossil fuels off California’s grid.

That’s firmly in line with the state’s current sustainability gestalt, which effectively mandates large-scale renewable energy development in pursuit of abundant clean power. With President Donald Trump dismantling previous efforts to green America’s energy portfolio, California is leading what amounts to a state-based eco-insurrection. By leaps and bounds, the Golden State is the nation’s forerunner in reducing reliance on fossil fuels, a conversion it has dedicated itself to with born-again devotion.

Introduced in May, Senate Bill 100 would require California utilities to procure 100 percent of their energy from renewable sources by 2045. The bill was supported by the solar industry but faced last-minute pushback from utilities unions. It was recently tabled until next year, when supporters plan to resurrect the effort. But even without S.B. 100, California’s existing green energy obligations are towering: It must get 33 percent of its energy from renewable sources by 2020, and 50 percent by 2030.

“Let’s talk about state pressures. There’s Senate Bill 100 and there’s Assembly Bill 1405,” says Gallagher. (A.B. 1405 requires utilities to deploy more clean energy during peak demand). “Both are talking about green energy. Getting away from fossil fuels. They’re saying solar panels are good. Wind farms are good. They’re saying you need to develop those throughout the state.” But, says Smith, it’s important to do this smartly, with precision targeting. “You do solar only on degraded land,” she says — not a natural habitat like Tres Hermanos Ranch. “I am not against green infrastructure or these new solutions. But I’m not ever going to be in favor of any project that is done so stupidly, out of sequence, out of order.”

This wouldn’t be the first time California has imposed unwelcome renewables infrastructure on this area. In April 2012, a U.S. House subcommittee held a hearing in Chino Hills on the impact of new high-voltage transmission lines on local housing prices. According to the subcommittee, the lines would “interconnect renewable wind energy to the existing electricity system in order to meet the state’s renewable energy requirements.” Over the course of the hearing, residents voiced a range of concerns about the power lines, claiming that they had diminished the value of their homes by 20 percent, that they attracted lightning, that it was “embarrassing to live near these towers” — the familiar public pushback that has engulfed many a large-scale public works project.

And yet, while some residents may be primarily concerned about falling house prices and ugly views, Gallagher and Smith appear genuinely worried that this type of “green” development is a shortsighted fix that Southern California will someday regret. “We’re trying to save this before they wipe it out and then get more problems and say, oh, now we have to fix it,” says Smith — an understandable concern from an L.A. native. This is a region that knows firsthand how following development trends that seemed innovative at the time can come back to haunt you decades down the road. The environmental crisis the state is now trying to build its way out of was created, in part, by urban land use practices pioneered right in Southern California.

“It’s this insane push toward the older ways of development,” says Smith of the notion that mandating new construction on natural greenfield is the path to environmental salvation. “Either we do crap development just to get the quota in, which has permanent consequences, or we talk to the state and say, there is no more room. We are full. Done.”

Growing Into Tomorrow’s Electrical Grid

At one point during our conversation, Smith says something that makes me pause. Tres Hermanos doesn’t need a solar farm, she says, because “our state has a surplus of solar energy.”

It’s a bit more complicated than that, but the gist is true: Even as California races to add more solar to its electrical grid, it’s sometimes overwhelmed by the large amount it has now. It’s a paradoxical quirk of transitioning to a next-gen energy system, one that the California Independent System Operator (CAISO) is charged with mitigating on a daily basis.

CAISO manages California’s electrical grid from a highly secure building in Folsom, California, a location chosen for its minimal seismic activity. Shielded from the road by earthen berms and guarded by multiple checkpoints, it is the nerve center for the intricate system that keeps the lights on in the world’s sixth-largest economy. At the heart of the building is its subterranean control room, a darkened theater-like space fronted by a concave wall of digital screens displaying real-time grid conditions. From banks of U-shaped desks facing this wall, engineers monitor substations, track voltage output, combat outages and keep an eye on maps charting temperatures and wildfires.

Their jobs occur on a second-by-second basis. During my visit, one engineer was on the phone trying to resolve a voltage disruption indicated by a flashing red bar on one of the screens. In the center of the room, a floor manager stoically eyed the situation. Behind him, other engineers kept tabs on their own screens. The tableau had the taut frisson of air traffic control.

CAISO has a long-term task to tackle, as well: It must figure out how to make Sacramento’s ambitious renewables mandates work on a century-old grid. Its next deadline is 2020, when one-third of California’s energy must come from renewable sources. “This grid is ready for that,” says Steven Greenlee, CAISO’s senior public information officer.

Re-engineering a statewide energy system to accommodate renewables is an imposing undertaking. It means the grid needs to become more flexible than it was under fossil fuels alone, which are dirty but fairly predictable, unlike highly variable solar and wind. Today, when the sun comes out in the morning, solar energy floods into California’s grid. Between 9 a.m. and 11 a.m. it can saturate transmission lines at 50 megawatts per minute. Because this electricity can’t be stored, says Greenlee, “between 9 and 11 in the morning, we have more solar on the grid than we can use. And this problem is getting worse.” Worse, because California is adding solar capacity at an extraordinary pace, racing to hit its renewables benchmarks and go at least 50 percent green by 2030.

But the grid still has its old natural gas plants, as well — it needs them for nights and cloudy days. So, when the sun comes out or the wind blows hard, all that clean energy can temporarily overwhelm the grid. “Managing that oversupply is a great challenge,” says Greenlee. “We can’t just turn stuff off.”

How CAISO manages this excess power is a complex process involving commodity markets, negative pricing and interstate energy management structures — you can read about it here. But the general problem boils down to this: California renewable energy is in an adolescent growth-spurt phase, its generation sometimes surging upward faster than consumers can use it. The state is intentionally building more solar plants than it needs today in pursuit of the dream of a fully decarbonized grid to be realized decades from now. For those being asked to accept this energy infrastructure in their towns, however, the fact that its production is frequently dialed back or shipped to other states is understandably frustrating.

According to Greenlee, solving the oversupply conundrum and getting the state to the renewables-only finish line will require two primary fixes. The first is technological: Renewable energy power plants need to learn to ramp up and down quickly so that when one solar farm is shrouded in clouds, another can pick up the slack. Wind farms can take the graveyard shift, since wind in Southern California blows hardest at night. Hydro, thermal and biomass power can contribute their fair share, too. Once upgraded technology allows these various plants to work in harmony, California can take its natural gas plants offline and more deftly balance the renewables on the grid.

The other fix is bureaucratic. Though the wind and the sun don’t stop at state lines, CAISO’s regulatory jurisdiction does, which makes swapping energy with other states less efficient. Greenlee envisions a broader, regionalized system, as is the case with the independent system operators in the smaller states in the East, which are able to trade power more seamlessly.

Solutions to these challenges will arrive incrementally. In the meantime, however, as the state’s share of renewable power continues to climb, each new solar plant is a fresh source of volatility on the grid. California may not produce the most renewable energy in the U.S. — that honor belongs to Washington, thanks to the awesome hydropower it reaps from the Columbia River. But where California does lead is in tackling the challenges that must be solved to realize a green energy future. No state is taking more risks, pushing more boundaries or asking its residents for more shared sacrifice. By adding renewables to its system at a rate of 2,000 megawatts per year, California is on track to increase its renewable energy by 15,000 megawatts by 2030. It’s a pace of change that practically begs for bumps in the road. “We’re in that messy stage of transition,” says Greenlee. “We’re evolving a hundred-year-old grid into something that will work for the future, and we’re getting there.”

A History of Fighting Density

When I bring up this notion of shared sacrifice to Robin Smith — the idea that, to achieve 100 percent clean energy, all Californians might have to give up something they love — her response is emphatic. “It’s a complete waste to put the solar panels in a pristine natural habitat and not put them on their many hundreds of warehouses,” she says, referring to the warehouses in Industry. “It’s a no-brainer. It’s like me saying, instead of putting solar panels on my roof, I’m going to put them on my acre slope and wipe out my oak trees.”

There’s a reason people move out to Chino Hills and Diamond Bar. The unbuilt terrain is a respite from the clogged, infinite asphalt of the L.A. megalopolis. Tres Hermanos itself got its name from the trio of wealthy Los Angelenos (the “Three Brothers”) who purchased it as a refuge from the rapidly urbanizing city in 1914. One of them was Harry Chandler, the powerful publisher of the Los Angeles Times. Another was a former L.A. County sheriff and the third, ironically, an oil man. Smith worries that Industry might seize the mantle of “environmentalist” simply because it’s talking about turning that refuge into solar — a false flag, she believes. “We have passive value here, like a national park,” she says. “Is there another option? That’s what conservation planning is.”

Fair or not, however, it’s this “national park” part of the argument that opens local advocates to accusations that they simply want to preserve their backyard playground. In his groundbreaking 1990 book on Los Angeles urbanism, “City of Quartz,” Mike Davis writes of “a California neologism of the 1980s [that] perfectly encapsulates this ethos of untranscendable parochialism: nimby.” Davis was one of the first to popularize NIMBY, now a household acronym, in the context of Southern California’s slow-growth movement, which restricted density and development in the 1980s.

It’s a complete waste to put the solar panels in a pristine natural habitat and not put them on their many hundreds of warehouses. It’s a no-brainer. It’s like me saying, instead of putting solar panels on my roof, I’m going to put them on my acre slope and wipe out my oak trees.

Davis chronicles how Proposition U, passed in 1986 with the support of grassroots political groups like Not Yet New York, curtailed density levels throughout Los Angeles, and how this ideology spread eastward to the area around Tres Hermanos. “Once the world’s greatest citrus belt, the San Gabriel Valley, like the San Fernando, has been subjected to acute growth stress over the last generation,” writes Davis. “Meanwhile, in the Valley’s rapidly urbanizing eastern half (especially along the growth corridor of the Pomona Freeway), which gained almost a quarter-million new residents in the 1980s, commuter-suburbanites have organized to slow development and preserve their remaining rural amenities.”

Twenty-seven years later, that struggle endures. But are attempts to preserve open space rooted in NIMBYism or forward-thinking land use priorities? The answer to that question depends on how you feel about California’s current approach to environmentalism, which favors statewide, top-down, large-scale mega-endeavors. It has to, if it’s going to keep up with the legislature’s aggressive green energy benchmarks. In this context, for better or worse, Industry’s ideas for Tres Hermanos would seem to have the edge, and talk of leaving the land alone because “the earth is doing what she does,” as Smith puts it, can come across, perhaps unfairly, like a 1960s solution to a very modern problem.

Solar Power Fitting In

Maybe there’s a middle ground. In Downtown Los Angeles, the Los Angeles Cleantech Incubator (LACI) is cultivating smaller-scale renewables solutions for the region’s future. Located on a barren stretch of industrial road at the La Kretz Innovation Campus, the initiative is directed by Matt Peterson, L.A.’s former chief sustainability officer.

Peterson knows something about getting people behind a green energy agenda. In 2003, as president of the environmental nonprofit Global Green USA, he organized the now-famous spectacle in which Cameron Diaz, Harrison Ford and a slew of other A-listers showed up at the Academy Awards in Priuses, which Peterson borrowed from a local Toyota dealership. “That first generation Prius was a tin can,” says Peterson. “But it was around the Iraq War, right after 9/11, and the photograph was literally the car at the red carpet.” It was product placement straight out of the Hollywood playbook. “People went, ‘Oh, wow. I could drive a hybrid car, too,’” he says. “It advanced our goal, which was to make hybrid cars fun and sexy to drive.”

Today, as president of LACI, Peterson is bringing that green sexy back. Throughout the building, young entrepreneurs brainstorm in offices decked out with Apartment Therapy-worthy artwork. Many of LACI’s portfolio companies are online enterprises, like EV Connect, a network management platform for electric vehicle charging stations, and Pick My Solar, a business aggregator that Peterson describes as “the Kayak of solar.” But the building also houses several actual working laboratories outfitted with welding equipment, 3-D printers and a precision water jet that can cut through eight inches of steel — state-of-the-art machinery the startups can use to prototype parts and devices for everything from electric aircraft to plasma lighting for movie studios.

One of these companies is Nevados, which is developing a single-axis solar tracker that can be installed on sloped and rolling terrain without the need for grading the land. Single-axis trackers, as opposed to fixed tilt systems, can rotate solar panels to directly face the sun, making the solar panels more efficient. But they can generally only be installed on flat terrain. “Ours can articulate along the length of the row, like the drive shaft of a pickup truck,” says Yezin Taha, founder of Nevados, meaning they can be installed with minimal impact on a slope.

I thought of Tres Hermanos Ranch and its sun-baked hills, which I had stood atop with Robin Smith and Jim Gallagher under a crystal clear sky a few days earlier. “I think there are a lot of places in these hills where you could put solar panels and you wouldn’t even see them,” Gallagher had said. Truth be told, he’s flexible on the solar option, as long as it’s at a reasonable scale and done correctly. “If we were talking about 2,000 acres [of solar], I think that’s way too much. I could see maybe 500 acres, way in the back so it doesn’t disturb anybody.” He even brought up the benefits of the type of panels Nevados produces, which don’t require grading. “You can also least disturb the land when [the panel] is on a pole, where you don’t have to grade the land to do it.”

To Smith, however, this talk of how much solar misses the point. She believes that once you open that door to development, it’s virtually impossible to close. She doesn’t trust Industry not to use the opening to develop the entire ranch, or the environmental consultants not to underreport the panels’ impact on the land. She believes that the state will fail to enforce its own laws, that the local City Council is bought and paid for. “I have learned there’s a lot to know about solar,” she says. “It is not an open-and-shut case like everyone thinks. I’m not the kind of consumer who just grabs the next fad and thinks we’re fixed by things. Because as you know, we do a lot of backpedaling, and that’s what frightens me. Because there is no more room for mistakes.”