How to Protect Puerto Rico’s Power Grid from Hurricanes

Puerto Rico’s power grid has taken several hits from recent disasters. Hurricane Maria, a devastating and deadly storm, ravaged the island in 2017, causing widespread damage and months of excruciating power outages for many residents. It took almost a year before the last house was connected to the grid again.

This storm highlighted the fragile state of Puerto Rico’s power grid and prompted change. In 2020, the Federal Emergency Management Agency (FEMA) provided the Puerto Rico Electric Power Authority (PREPA), the island’s bankrupt public utility, with nearly $9.5 billion to repair the electrical grid. By mid-June 2022, $12.8 billion was earmarked for PREPA in partnership with LUMA Energy, the company that took over the grid’s transmission and distribution operations in June 2021, to improve the system. But the deployment of funds has been slow and the service remains extremely unreliable. In April, a power plant fire left the island in the dark. And this month, almost five years to the day since Maria landed, Hurricane Fiona unleashed more than 30 inches of rain on some parts of the island, causing flooding and mudslides. The damage led to another island-wide power outage. At 8 a.m. local time on September 27, more than a week after the storm, around 500,000 of the approximately 1.5 million customers were still waiting for the power supply to be restored.

Scientific American spoke to Kaitlyn Bunker, Max Lainfiesta, and Michael Liebman — three members of the Islands Energy Program team at the Rocky Mountain Institute, a nonprofit energy research organization — about Puerto Rico’s power grid, efforts to improve grid resilience, and the role of renewable energy in that process. The islands’ energy program is working with local partners to facilitate the islands’ transition to clean energy. Lainfiesta and Liebman were speaking from San Juan, Puerto Rico, where they were working with local partners on microgrid systems using solar power and storage. Bunker spoke from Boulder, Colorado.

[An edited transcript of the interview follows.]

How functional was Puerto Rico’s power grid before Hurricane Fiona made landfall?

LAINFIESTA: Hurricane Maria destroyed the grid. After the hurricane, they just restored the network [enough] to make it work. But there was never any improvement or preparation for the next event. As a result, Fiona – in what is incredibly the first major storm to hit the island in five years – has left virtually the entire island without power.

For the past five years, the power situation on the island has been in the news every day. They get into a taxi and the driver starts talking about electricity. You listen to the radio, you will always hear how bad the electricity system is. Power problems are an everyday problem.

What was the situation in Puerto Rico in the days immediately after the last storm?

LAIN FIESTA: [At the time of this interview on September 20] there is no water. 80 percent of the population are currently without electricity. And there is no information as to when the power or water will be restored. It’s quite messy for a lot of people, especially in poor neighborhoods where there are these flooded areas that need a pump to drain the water and either the pump has no power or the pump is damaged or submerged. It is a supercritical situation in many places. [Editor’s Note: LUMA released an estimated time line of restoration on September 25.]

What exactly caused the power outages?

LAINFIESTA: It is uncertain. I’ve been trying to figure out exactly why we don’t have electricity. There is a total lack of information about it. Scattered information suggests the generating units are operational, but the transmission and distribution infrastructure is the problem at this point. I’ve seen some crews on the news trying to fix a very critical substation and restore some of the grids. I would like an answer to this question, but unfortunately I still don’t know what the reason is. I tried to find out.

BUNKER: We don’t know many details about what’s happening in Puerto Rico right now, why the network went down. However, we suspect this is largely due to the system’s design, which is not specific to Puerto Rico. Most of the other islands in the Caribbean that we work on, as well as larger countries like the US, have a similar design where it’s very centralized. There are some large generating plants that produce the electricity. They are often located far from the homes of the people who use the electricity. There is a very interconnected system of transmission lines that carries this electricity to the people who use it. If there are problems with all those lines that usually run overhead, the power is cut off.

LIEBMAN: LUMA is responsible for transmission and distribution, so they would respond to that. But they faced many challenges. This organization had no involvement in Puerto Rico prior to June 2021. They really struggled to respond to outages and keep the transmission and distribution lines running. [Editor’s Note: Mario Hurtado, chief regulatory officer of LUMA, told Scientific American that the company inherited a neglected grid. He added that while the grid has continued to underperform since the company took over, LUMA has made important progress.]

Long transmission lines appear to be suboptimal in areas prone to natural disasters. What are some possible alternatives?

BUNKER: Part of our approach with our partners in Puerto Rico and the wider Caribbean is transitioning to a much more distributed system where generating resources are close to the people who use them. And after an event like this, for example [those generation sources] could continue to power a building or buildings in a community to sustain critical power demand while the larger grid may be down.

How much progress has there been in this regard since Hurricane Maria?

BUNKER: We have seen some positive movements in terms of renewable energy implementation, particularly at municipal and decentralized levels, and a focus on the most critical infrastructure: schools, clinics. And there are some great examples of those solar and storage projects that have weathered this latest storm – they were undamaged and are now operational, delivering power locally. That’s wonderful to see. It just hasn’t happened on the scale that we know it needs to happen to affect more and more people across Puerto Rico.

Why do you think renewable energies are so important for grid resilience?

BUNKER: There are good solar resources in Puerto Rico. Once it’s installed, you’re using a local resource as opposed to something that needs to be imported [such as natural gas or diesel]. This is a potential point of failure – when you rely on a resource that needs to be imported and you can’t get that resource. If you only put up solar, it may be damaged in a storm. But there are ways to get the design and installation to withstand the stronger storms, allowing the resource to survive the storm and then use a local resource to generate electricity. [Editor’s Note: Hurtado told Scientific American that LUMA believes renewable energy sources are important for Puerto Rico’s grid. He said the company has been “very aggressive” in connecting residential solar installations and that it is on track “to triple the amount of utility-scale generation in Puerto Rico within a couple of years.”]

Could it also help overcome the challenges of transmission?

BUNKER: Yeah, that’s the other important piece because [renewable energy systems] are quite modular and flexible. You can look at where the most critical infrastructure is, where the most power is needed to stay constant, whether there’s a storm or not, and where renewable energy is. They are located on a roof, possibly in a carport or in a parking lot, also on the ground. But there are just a lot more options where you can put that. And you can undertake a smaller or larger project, depending on your needs and the space available. [Editor’s Note: Hurtado told Scientific American that a strong grid—including centralized transmission—will also be essential for meeting current needs and building out renewables. “You need a more sophisticated, stronger, more resilient grid in order to enable renewables. There is no heavily renewable or 100 percent renewable future without investing significantly in the grid,” he said.]

How does equity fit with the shift to renewable energy and the pursuit of a more reliable and resilient energy system?

LIEBMAN: From an economic standpoint, Puerto Rico has really struggled. If Puerto Rico were a state, it would have the highest poverty rate and the lowest GDP [gross domestic product] per capita in the country. With these solar-plus-storage and micro-grids, it means these benefits stay with the communities when deployed properly.

LAIN FIESTA: While we fully support the use of renewable energy in all sectors, we particularly want to ensure that people in low- and middle-income communities can participate. Since Maria there has been massive deployment of renewable energy at the household level in Puerto Rico. But of course only for those sections of the population who can afford it. We want to go renewable – but we need to put equity in the equation.