As Hurricane Maria churned menacingly toward Puerto Rico on 19 September, Gary Soto was hunkering down on the outskirts of San Juan. Soto, the operations manager of Puerto Rico’s state-run utility, faced a daunting task: to keep the grid running and minimize damage from the storm.
In a windowless, wood-paneled control center at the Puerto Rico Electric Power Authority (PREPA), Soto and a dozen other engineers and supervisors worked at U-shaped desks littered with paper coffee cups, staring at computer monitors that displayed real-time conditions on the grid. One after another, transmission lines were failing, and the team hastily debated their course of action. In this fragile state, the network wouldn’t be able to absorb an oversupply of power, excess voltages, or swings in frequency. They could inject test currents into the downed lines, to see which ones could be restored, or else reduce the level of electricity being put on the grid, to protect the remaining transmission system. Hour after hour, the team’s chatter filled the room with rising urgency.
As Maria veered closer, Soto recalls, and its true magnitude became apparent, he thought anxiously about his wife and two young daughters, at home in the coastal town of Dorado.
By nightfall on the 19th, the PREPA crew knew their efforts were futile. Outside, winds topping 280 kilometers per hour had begun toppling transmission towers, snapping concrete power poles, entangling lines, and battering power plants. The PREPA engineers at their workstations watched in dismay as small outages spread and bloomed like a virus. Finally, at 2 a.m. on 20 September, Soto says, “We went into total blackout.”
All of Puerto Rico was now in the dark.
Four hours later, Maria barreled into the island as a Category 4 hurricane, the strongest to hit Puerto Rico since 1928. The storm tore a diagonal 160-km-long path from the island’s southeast to its northwest, demolishing tens of thousands of homes, washing away roads and bridges, stripping the limbs from lush green palms, and leaving in its wake a littered and jarringly lifeless landscape. Unofficial tallies after the storm suggest that about 1,000 people lost their lives.
In the months to come, Puerto Ricans—who are, after all, citizens of the United States, a country of unquestioned technological preeminence—would discover how breakable their modern society actually was. Water treatment facilities couldn’t provide drinking water, markets and restaurants couldn’t refrigerate food, banks couldn’t operate ATMs or conduct transactions. Cellular and Internet access was gone. Street lights and traffic lights stopped working. Schools, hospitals, and stores closed indefinitely. Puerto Rico’s factories shut down; tourism ground to a halt. After the storm, 200,000 Puerto Ricans decamped for the mainland United States in search of jobs, medical care, or just modern comforts. As of early March, more than four months after the storm, 84 percent of PREPA’s nearly 1.5 million customers had power. But U.S. officials were saying that remote areas in “challenging terrains” would not get service until the end of May.
The restoration of Puerto Rico’s power grid is a timely object lesson on the vulnerabilities of modern electrical networks and on the emerging technological options for minimizing those vulnerabilities. Power experts are now not just repairing Puerto Rico’s grid but doing so with an eye toward a future that portends storms of increasing intensity and frequency. Grid operators around the world are considering the merits of microgrids, utility-scale energy storage, and distributed and renewable generation. But for Puerto Rican officials trying to rebuild their shattered electrical infrastructure, these possibilities are of much more than abstract interest.
This past December, I traveled to Puerto Rico to report on this massive undertaking, to see how engineers are restoring power to the island’s 3.4 million residents. I found contradictions everywhere I went. I saw utility workers fanned out across the island, yet progress remained excruciatingly slow. I met rank-and-file PREPA employees working flat out to restore power, yet each day brought a new report of fumbles at the utility’s top levels. I dined in the dark in Old San Juan, after the restaurant’s power cut out yet again, then strolled through a bustling shopping mall glittering with Christmas lights. And I heard many smart and exciting ideas for how to build a modern, resilient grid in Puerto Rico, even as the urgent need to restore power meant resurrecting the vulnerable existing system.
Hours after the storm cleared, Soto drove home to Dorado through a surreal scene of fallen trees and debris. Abandoning his car at a washed-out bridge, he walked the remaining 8 km to his house, where he was relieved to find his family unharmed. The next day, he made his way back to the PREPA control center.
Step one was to figure out what exactly had happened, all over the island. The control center was running on a diesel generator, but island-wide communications were down. That meant the usual way of gauging conditions on the grid—using automated remote terminal units at substations to collect and send data to the central SCADA (supervisory control and data acquisition) system—didn’t work. PREPA’s grid reaches nearly every home, business, school, and hospital on the main island, as well as on the smaller islands of Vieques and Culebra. For months, the utility was unable to say just which customers were still in the dark. At first Soto and his team relied on outage reports coming in via satellite phone and from amateur radio operators.
Under normal conditions, Puerto Rico’s generating capacity exceeds 5,800 megawatts, but peak demand is only around 3,000 MW. About half of the electricity comes from PREPA’s 10 oil-fired power plants. Much of the rest is produced by a pair of natural-gas power plants and a coal plant. Renewables—including seven solar farms, two wind farms, and seven hydropower sites—supply just 2.4 percent of generation.
On a sweltering morning in December, Soto stands before a colorful SCADA map projected on the wall of the control center. He points out the grid’s lopsided nature: Seventy percent of Puerto Rico’s power generation is in the south, while 70 percent of power demand is in the north. This disparity reflects decades-old decisions to build up the island’s manufacturing base. Back in the 1970s, mainland U.S. companies were lured to Puerto Rico by a generous corporate tax incentive, and many sited their factories in the south. Accordingly, PREPA expanded its power generation and transmission infrastructure to service those facilities. But in 1996, the U.S. government began phasing out the tax break, and manufacturers moved overseas. Now PREPA’s biggest customer base is on the other side of the island, centered around San Juan.
Soto sweeps his hands across the middle of the map, indicating the south-to-north transmission lines that bisect the island. “This is one of the biggest problems of how PREPA is configured,” he says. Hurricane Maria sliced straight through these vital connections, only 15 percent of which were designed to withstand a Category 4 hurricane.
From the control center, Soto and I drive to a grassy clearing and climb into a PREPA helicopter. We rise up into the air, and buildings in San Juan’s outskirts soon give way to undulating green mountains and plunging valleys, the bright blue Atlantic Ocean glimmering in the distance.
The transmission system consists of 4,000 km of line divided among three voltages, Soto explains. The backbone is a 230-kilovolt ring around the island, with two south-north corridors dividing the island into western, central, and eastern loops. This feeds an extensive 115-kV network that delivers power to population centers. Finally, a 38-kilovolt “subtransmission” network serves remote areas, as well as Vieques and Culebra via underwater cable; it also supplies power to PREPA’s 51,000 km of distribution line.
As the helicopter veers southeast, scenes of unsparing destruction emerge. Steel lattice transmission towers lie in broken piles. High-voltage wires wrap around treetops. We fly over the Punta Lima wind farm, where the masts of turbines, their blades shorn off, stick up like fat white flagpoles. Near the beach town of Humacao, a large solar farm has been reduced to fields of broken glass and twisted metal. Blue square tarps dot the landscape; these temporary roofs are all that shield the buildings’ occupants from the elements.
In the distance, another helicopter is lowering a replacement tower to an ant-sized crew in the clearing below. The storm damaged, destroyed, or otherwise compromised 80 percent of the island’s grid, according to the U.S. Army Corps of Engineers, which is in charge of its reconstruction. Of 334 substations, nearly 40 percent suffered major harm. Some power plants were hardly touched, while others were devastated. The largest facilities were operational within weeks but couldn’t export their power to the grid until the network was repaired.
A storm the size of Maria would have wreaked havoc on any electric system in its path. But Puerto Rico’s grid was especially vulnerable to extreme weather, and the utility was ill-equipped to respond. Decades of mismanagement and questionable practices, such as providing power at no charge to state-run enterprises and municipal governments, left PREPA US $9 billion in debt. Puerto Rico’s decade-long recession, shrinking population, and declining manufacturing sector further eroded revenues. To stem costs, PREPA halved its workforce, leaving the remaining 5,000 employees, like Soto, to juggle multiple roles. Routine maintenance, like clearing brush impinging on power lines, got deferred, and aging equipment wasn’t replaced. Last July, PREPA filed for bankruptcy.
Traveling around the island, I see signs of PREPA’s decline everywhere. Along a small creek, houses and fences have been built directly on an access road leading to transmission lines. Repair crews have had to either airlift in replacement parts or haul them in through people’s yards. In a San Juan neighborhood, a yellow excavator scoops thick mud. Over the years, a nearby lagoon has taken over a right-of-way, filling it with goop that’s bogging down workers’ trucks.
“This is like a storm within a storm within a storm,” Carlos Torres, a former vice president of emergency management at Consolidated Edison in New York and the top person overseeing the island's power grid restoration, said in a presentation to utility workers in San Juan.
In a ballroom at the Sheraton Hotel in San Juan, dozens of utility engineers and supervisors gather on a December morning. Newly arrived on the island, they crowd around large round tables covered with notepads and bowls of candy bars. They hail from utilities in Arizona, California, Massachusetts, New York, and Texas, and they’ve come to help.
It took PREPA officials more than a month to formally request such mutual aid. On the mainland, these requests typically occur much sooner—perhaps even before a major storm strikes—triggering a flow of personnel, equipment, and material to the affected area. PREPA, however, turned to private contractors, a move that proved wildly controversial and eventually led its CEO to step down (more on that later).
In the ballroom, Eric Silagy, president and CEO of Florida Power & Light, gives the workers a pep talk. He urges them to adopt the motto of “One team, one mission” and persevere through any difficulties. They’ll be joining 3,500 or so others already on the ground.
“Back home, you know how devastating [a storm like this] would be,” Silagy says. “The people of Puerto Rico are counting on you. These U.S. citizens deserve to get back up on their feet as quickly as possible.”
Later that day, I run into crews returning from the field. “It’s all work, work, work,” says Alex Echeverría, director of relay protection and control engineering at the New York Power Authority (NYPA), as he watches the dirt-streaked, sweaty linemen shuffle into the Sheraton’s sprawling lobby. They’re still wearing their yellow safety vests and clunky boots as they make a silent beeline for the elevators.
Echeverría, who was born in Ecuador and has a lively sense of humor, landed in San Juan on 28 September with a team of drone pilots, NYPA supervisors, and engineers, sent there by New York governor Andrew Cuomo to help out with the recovery. “It was kind of helter-skelter,” the engineer recalled of those early weeks.
PREPA, still scrambling to respond, wasn’t prepared to delegate tasks, so the NYPA crew went looking for things to do. They surveyed transmission lines by drone and compiled status reports on every substation. Their first hotel, in Old San Juan, had no generator and thus no air-conditioning. With temperatures soaring above 30 °C most days, some workers took to sleeping on the tile floor.
Echeverría did a four-week stint and then returned for a second stint in November along with 450 New York utility workers. By the time I met him in mid-December, he’d settled into a relentless routine of 16-hour workdays. Each morning, he wakes at 5 a.m. and meets with repair crews and then updates PREPA officials. Meetings resume at 7 p.m., to review the day’s progress and map out the next day.
“It’s like Groundhog Day,” he jokes. “Every day is the same.”
During my time on the island, electricity had been largely restored in the bigger cities, including San Juan in the north, Ponce in the south, and Mayagüez in the west. But the more remote areas and even a few urban neighborhoods still lacked power. Service continued to be unreliable, with transmission lines occasionally faltering or crews de-energizing wires to do repairs.
Col. John Lloyd, the officer leading the Army Corps’ power-restoration mission in Puerto Rico, explains the frustratingly slow progress. A week after Maria, the U.S. Federal Emergency Management Agency (FEMA) tasked the Army Corps with restoring Puerto Rico’s grid to prestorm conditions. The military agency has since provided the lion’s share of manpower and resources on the island.
At his task force’s headquarters in San Juan, Lloyd wears his usual work attire of combat fatigues. Around him, workers hunch over laptops at folding tables, each table representing a region of the island. He ticks off a few of the many complications confronting his team: decades-old grid infrastructure in disrepair, including broken “blackstart” diesel generators that would ordinarily be used to jump-start larger generators after an outage; the island’s mountainous, forested interior, which necessitates transporting crews and material by helicopter; the fact that Puerto Rico is an island, which means much-needed equipment gets hung up at the port.
“I can’t overstate enough the magnitude of some of these challenges,” Lloyd tells me. “The amount of material necessary to do the restoration and the terrain we’re operating in are huge factors that drive a lot of the schedule and timeline.”
Nevertheless, as of late February, the Army Corps had brought in nearly 1,000 emergency generators. Truck-size 1-MW units went to hospitals and other critical facilities, while 25-MW units went to damaged power plants. The unit also received nearly 4,500 km of wire and more than 37,000 wood, concrete, and galvanized steel poles; another 13,000 poles were slated to arrive this spring. At first, supplies barely trickled onto the island, in part because inventories across the United States had been depleted by the disastrous 2017 hurricane season and wildfires in California.
A final factor slowing down the recovery is PREPA’s poor choices in the storm’s aftermath. In November, Ricardo Ramos, PREPA’s CEO at the time, told the U.S. Senate’s Committee on Energy and Natural Resources that his cash-strapped utility was “unable to meet the requirements” for mutual assistance, so he didn’t request it. These requirements include providing water, food, and shelter for the visiting workers.
Instead, PREPA quietly inked a one-year, no-bid contract for $300 million with Whitefish Energy Holdings, a two-person firm in Montana with little experience in grid repair or disaster recovery. Ramos said of the six contractors he considered, Whitefish was the only one that didn’t stipulate a large up-front deposit. Close scrutiny of the contract revealed unusual provisions, such as higher-than-normal rates for labor, per diem expenses, and travel—as well as a clause stating the work could not be audited.
A second no-bid contract for $187 million went to Cobra Acquisitions, a subsidiary of the Oklahoma-based fracking company Mammoth Energy Services. Like Whitefish, Mammoth has no experience with a recovery project this big. Its contract also stated that the firm could not be audited, although Cobra eventually agreed to remove that language. That contract has since swelled to $945 million, a fivefold increase.
PREPA officials have denied any wrongdoing, and Whitefish and Cobra note that they each deployed hundreds of crew members and shiploads’ worth of heavy equipment. The contractors’ linemen helped advance initial repair work along a handful of transmission lines, PREPA’s Soto confirms.
However, the controversy over the contracts and the slow recovery infuriated Puerto Ricans and further eroded public trust in the utility. Finally, on 31 October, Ramos announced that PREPA was canceling the Whitefish contract, and he requested mutual aid from the American Public Power Association and the Edison Electric Institute, industry groups that represent hundreds of utilities. On 17 November, Ramos resigned.
In early November, more than a thousand public utility workers began making their way to Puerto Rico. Keith Ladue, a chief lineman with NYPA, arrived on 9 November for a five-week stint. The extent of the damage shocked him. Everywhere he looked, poles and wires were lying on rooftops or on the ground. “People don’t realize how bad it is until they see it for themselves,” he says.
Wearing dark sunglasses and a bright orange hard hat, he stands atop a red dirt hill in Guaynabo, a western suburb of San Juan. “Go as slow as possible,” he says into a walkie-talkie, watching as linemen in a bucket truck secure a 115-kV line to a new steel pole. Green iguanas scurry in the tall grass by the road.
Ladue, who hails from Massena, N.Y., near the Canadian border, has a lot of experience doing repairs in rugged terrain. But Puerto Rico is something different. The pole they’re installing should be in a right-of-way, but instead it’s in the middle of a neighborhood, surrounded by houses and cars. The crew has to maneuver cautiously to avoid damaging private property.
Still, Ladue says, the work has been rewarding. Neighbors bring the crew home-cooked meals and cheer “New York Power!” as they walk by. A nearby café serves them free coffee.
“The locals are very understanding,” Ladue says. “They’ve been excellent to us.”
For many Puerto Ricans, the sudden arrival of bucket trucks and linemen is often their only indication that power may soon be restored. PREPA officials, many residents complain, give few if any status reports.
Lucía Martín, a school vice-principal in San Juan, says the uncertainty has been paralyzing. “It’s the not knowing,” she tells me. “You can’t make any decisions.” Martín stands with a crowd of people outside PREPA’s San Juan control center on 15 December, and she holds a small sign that reads “Informen la verdad”—tell us the truth. She helped organize this protest with residents from two dozen communities that still lack power.
At Martín’s school, teachers have moved their classes outside. Her home hasn’t had power for nearly 100 days. During the protest, though, she receives a welcome phone call: Her lights just came back on.
Like Martín, many Puerto Ricans haven’t been inclined to wait patiently in the dark. They are finding ways, big and small, to help themselves and each other, to share information and even electricity. At Bebo’s Café, a well-known restaurant in San Juan, the owner set up outlets fed by rooftop generators so that people can charge their phones. Ivette Vizcarrondo would bring her 5-year-old son, Sergio, to the restaurant several times a day. Sergio has severe asthma and uses a nebulizer, a plug-in device that dispenses medication through a face mask.
One afternoon at Bebo’s, they happened to meet solar power engineer Gabriel Rivera, who suggested a better way. Rivera had been volunteering in the neighborhood, collecting the names of residents in need of medical assistance. He saw that many, like Sergio, used simple but essential devices—such as adjustable hospital beds and minifridges to store insulin—that could easily run off small emergency solar systems. Rivera and a colleague, Beatriz Menéndez-Conde, got to work assembling and donating the systems. One of the first recipients was Sergio.
Rivera and I visit the Vizcarrondo apartment and climb the stairs to the rooftop. He shows me the single 255-watt solar panel he’s placed there, next to a small inflatable swimming pool and some plastic toys. A long yellow cord runs from the panel, over the roof’s edge, and onto the apartment’s balcony. The cord feeds a 20-ampere charge controller, a 500-W inverter, and two deep-cycle lead-acid batteries, all sitting inside a black plastic tub. Rivera had to scrounge around for every part; he picked up the batteries from an auto parts shop on the other side of the island. (He’s since refined the systems, which now use sealed absorbent glass mat batteries and larger inverters stored inside white cabinets.)
Even though power was restored to her building in early December, Vizcarrondo continued to use the solar kit for another month. The electricity was free and reliable, and she felt grateful that it worked for her son when nothing else did.
After Maria, such off-grid solutions have proliferated across the island. “We decided as a company that something drastic needed to be done,” Blake Richetta, a senior vice president for the German energy-storage manufacturer Sonnen, says by phone. Before the storm, Sonnen had worked with solar installation firm Pura Energia on residential solar-plus-storage systems. After the storm, the two companies pooled their resources to donate 15 systems in hard-hit rural communities, at a cost of around $350,000.
Jose Garcia, Pura Energia’s president, takes me to see an installation in Maricao, a tiny town in the western mountains. Fallen boulders and dried mud still cover the narrow winding roads. The Maricao system is set up in an abandoned grade school that became a temporary shelter after the hurricane. Two former classrooms serve as communal areas, with some computers, large fans, fluorescent lighting, and a washer and dryer. A pair of 3.5-kilowatt solar arrays on the roof charge two 8-kilowatt-hour battery systems.
Sol Ríos has been living at the Maricao shelter with her adult son and daughter ever since their apartment flooded during Maria. As of mid-December, they hadn’t yet found an affordable alternative. “We lost everything,” Ríos says, clutching her small, short-legged dog, Chivi. The shelter, even with electricity, is not home; she longs to return to her daily routine of cooking and running her household. “Here I don’t have anything to do,” she says, exasperated.
But for solar installers, the hurricane has been good for business. Garcia says there’s strong demand for solar-plus-storage systems as an alternative to the PREPA grid. “Now people are starting to talk about using PREPA as their backup,” Garcia says. “Two years ago, nobody was talking about that.”
On 24 January, PREPA announced a milestone: One million customers—roughly two-thirds of its residential, commercial, and industrial users—had their lights back on. The utility continues to boost generation, which is now at about 85 percent of what it was last year. Most of that power is coming from PREPA’s oil-fired units and a natural-gas fired plant. Other sites, though, sit idle.
For example, PREPA didn’t authorize the 24-MW solar farm in Guayama, on the south coast, to begin exporting power to the grid until late February, and then only at a 10 percent level. The utility says it’s concerned that intermittent flows of solar power would create instability on the recovering grid and that the area’s transmission network couldn’t support so much electricity. The 454-MW coal plant, also in Guayama, got authorized to export power in early February. Neither facility is owned by PREPA, so the utility has to pay their owner, AES Corp., for any electricity it uses.
Obed Santos, the solar plant manager, says the site was back to 74 percent capacity by mid-October. Under its contract with AES, PREPA has to compensate AES for its lost revenue. But given the utility’s severe cash crunch, payments are running late. AES got paid for its July 2017 power exports only in mid-February, Santos says.
“It has us all a bit worried,” he says as he walks through a field of solar panels. Flocks of sheep sit in their shade, chomping the grass.
Privately owned generation is a relatively recent addition to PREPA’s nearly 80-year-old operation. In 2000, EcoEléctrica became the island’s first independent power producer when it opened a 500-MW natural-gas power plant on the south coast; the AES coal plant and a handful of utility-scale renewables projects followed. Post-Maria, independent companies will likely play a much greater role in Puerto Rico’s electric system. In January, Governor Ricardo Rosselló said he planned to privatize the insolvent utility, in a last-ditch attempt to ease the island’s energy and debt crises.
Efrain O’Neill-Carrillo, a power expert at the University of Puerto Rico-Mayagüez, says that while privatization seemed inevitable, he worries that selling off PREPA’s centralized fossil-fuel plants risks locking in the existing system and slowing momentum toward renewable and distributed energy projects.
“Those new owners will want to maximize their investments. They would like to sell kilowatt-hours,” he says. “I’m not sure you’ll get many investors willing to buy those assets just to play a supporting role [on the grid].”
If Puerto Rico’s grid recovery has been slow and contentious, modernizing the island’s electric system will likely take many years, billions of dollars, and a lot of creative thinking. Of the last, there is no shortage.
In December, for example, a consortium of U.S. and Puerto Rican energy labs, agencies, and utilities published “Build Back Better” [PDF], a report that lays out a sweeping decade-long plan for strengthening and hardening the island’s transmission, distribution, and generation systems. The anticipated cost, at $17.6 billion, is fairly reasonable. In New York City, for comparison, Consolidated Edison has estimated that stormproofing its distribution systems by burying its overhead lines would cost an estimated $60 billion.
The Puerto Rico report recommends commonsense moves like installing Category 4–rated poles, wires, and insulators; building flood barriers around vulnerable substations; and adding fiber-based, high-speed data links between the field and control centers.
The report also champions distributed renewable energy as well as heavy reliance on microgrids. The latter are small electricity networks that can connect to the grid and also operate in isolation, combining solar power, batteries, backup generators, and control equipment. The group identified 159 sites where microgrids could be deployed, including hospitals, fire stations, and wastewater treatment plants.
Other ideas for fortifying Puerto Rico’s grid abound. Blake Richetta, of Sonnen, suggests adding software and data systems that could turn clusters of residential solar and battery systems into “virtual power plants.” These systems could be remotely controlled to supply power to the grid when and where it’s needed most.
“All the homes work together to share energy,” Richetta explains. “It makes it so there’s no way a Category 5 hurricane could bring down the grid—and it’s carbon free.”
Carlos Reyes, general manager at EcoEléctrica, sees an expanded role for natural gas. In addition to the natural-gas power plant, his company operates an import terminal for liquefied natural gas (LNG) and a regasification plant. Later this year, the company will begin a project to truck LNG to a handful of factories that have large generators. That should get the sites up and running more quickly after a grid outage and be less polluting than, say, diesel. Adding small-scale natural-gas generation to the island’s energy mix will help make the grid more flexible, Reyes says.
These disparate ideas share a common theme: a shift away from traditional centralized power plants and toward more distributed systems. For that to happen, government agencies have to agree on the plan. Microgrids, for example, still can’t connect to the main grid. The Puerto Rico Energy Commission is only now finalizing the rules [PDF] to allow that to happen.
O’Neill-Carrillo urges such regulatory roadblocks to be cleared quickly. “The present system is vulnerable to these disasters, and we cannot just build what was there before. We need to build something different,” he says. “We need to move away, as far as possible, from the centralized model and into something else.”
A shorter version of this article appears in the May 2018 print magazine as “Rebuilding Puerto Rico’s Grid.”
Maria Gallucci, a freelance science writer, is the 2017–2018 Energy Journalism Fellow at the University of Texas at Austin.