In Adjuntas, a town of 18,000 people in west-central Puerto Rico, 82-year-old Olga Hernández used to live in fear of every power cut.
An asthmatic and diabetic, she depended on ice to preserve her life-saving medicines and had to use a diesel generator daily when the regular power went out. The fumes it released sickened her.
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This story is part of Dialogue Earth’s work on the Community Adaptations to City Heat (CATCH) project, in partnership with Boston University. The project is funded by Wellcome. All Dialogue Earth content is editorially independent.
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“It was no life,” she tells Dialogue Earth.
But for nearly a decade now, a network of solar microgrids – small-scale electrical systems capable of generating and storing energy – has kept homes and businesses running, even during the frequent blackouts experienced in Adjuntas.
“With solar energy, I no longer feel the power cuts,” says Hernández.
Behind this energy autonomy is Casa Pueblo, a community organisation that puts energy in the hands of the people.
Microgrids can operate connected to the main grid, or isolate themselves from it during power outages to supply a hospital, a community, or even a whole city. They can also keep medical equipment running – something that can save lives when temperatures spike in a town like Adjuntas.
Power means life
Power cuts are a depressing fact of life for Puerto Ricans. Residents experienced an average of 73 hours of blackouts in 2024, according to official statistics. Forty three of these were attributed to “major events” such as hurricanes. Not accounting for extreme weather events, the average frequency of energy interruptions has increased since 2021.
Obsolete infrastructure, poor management, and allegations of corruption plague Puerto Rico’s electrical system. In 2017, Hurricane Maria exposed its fragility: nearly 3,000 people died in the largest blackout in the island’s history, many due to interruptions in medical care and life-support treatments.
In June 2024, a heatwave left more than 340,000 people in the capital San Juan and its surrounding areas without electricity. The temperature exceeded 48C in some areas.
“After Maria, we learned that blackouts kill,” Arturo Massol-Deyá, director of Casa Pueblo, tells Dialogue Earth. “We had no idea how many people depended on electricity to survive.”
Solar panels were first installed through the Casa Pueblo project in 1999. During and after the 2017 hurricane it became an energy oasis, supplying power to dialysis equipment, and oxygen and sleep apnoea machines. Meanwhile, parts of Adjuntas were left without power for six months. After the hurricane, these solar systems evolved into microgrids that have now been operating for nearly a decade.
Since then, the organisation has installed more than 3,000 photovoltaic panels across 400 solar projects, including Adjuntas Pueblo Solar, the country’s first urban microgrid. It supplies pharmacies, barbershops, pizzerias and other businesses. And it keeps Olga Hernández’s medicine cool. When Puerto Rico was hit by Hurricane Fiona in 2022, the power stayed on in Adjuntas for nine days, while other parts of the island were hit by blackouts.
“We’re not talking about energy independence for one house, but for the whole country. Puerto Rico can generate all its energy from the sun,” says Massol-Deyá.
The rise of microgrids
Excessive heat is pushing power grids to their limits across Latin America and the Caribbean, where millions depend on electricity to preserve medicines, operate medical equipment and cope with high temperatures. Drought can impact electricity generation that relies on hydropower. Additionally, demand can spike due to heightened fan and air conditioner usage, overwhelming supplies.
Microgrids have “the potential to save lives”, says the World Bank.
A 2022 handbook published by the World Bank includes estimates that 217,000 microgrids would need to be rolled out by 2030 to displace those systems and appliances generating power from diesel and kerosene. It claims this would provide universal access to clean power – and avoid 1.2 billion tonnes of CO2 emissions by 2030.
These systems are already finding favour in many countries.
According to one analysis, the global microgrid market exceeded USD 44 billion in 2025. North America accounted for the largest share, while Asia Pacific experienced the fastest growth.
In Latin America and the Caribbean, their deployment is still in its infancy. Historically, deployment has been linked to closing energy access gaps in communities beyond the grid, or where it operates only intermittently. There are many such locations in the region, amounting to an estimated 17 million people without electricity access as of 2022. Brazil is leading on deployment, while countries such as Chile and Peru are also interested in utilising the technology to electrify remote areas.
In Haiti, Honduras and other countries, microgrid networks already bring power to communities beyond the grid. The World Bank projects that by 2030, more than six million people in Latin America will be connected via a web of 1,800 microgrids.
When electricity reaches the desert
Southern Peru’s electricity transmission lines have failed to make the journey to Laguna Grande, a fishing village in the Paracas National Reserve.
“It was impossible for electricity to reach us because of the remoteness and because it is a protected area,” Esther Saravia, a fisher and chair of the community’s electrification committee, explains to Dialogue Earth.
Electricity arrived in Laguna Grande during 2016 via a solar and wind microgrid. It was initially financed by The Inter-American Development Bank (BID), then by Peru’s production ministry. This system generates 25-35 kilowatt hours of electricity per day and offers an “operational reliability” of 97%, according to the national government.
Laguna Grande is a classic example of how microgrids can be more cost effective than extending the grid in developing countries. That is according to Franco Canziani Amico, founder of the company Waira Energía that led the project: “They are the best alternative when the electricity grid does not reach an area, and even when it could reach it, they are often more competitive in providing clean, local energy.”
In Laguna Grande, energy costs USD 0.30 per kilowatt hour, while a generator would cost USD 0.37-0.74, according to Canziani Amico. The microgrid system operates on a pre-paid basis, and that money funds its maintenance.
Although there are no hospitals to keep powered in Laguna Grande, the impact on health has been experienced there, too. Before, without refrigeration, fish would spoil. “We used to bring ice every day,” says Saravia, who now stores food in a freezer. “It has changed our lives.”
Renato Errea represents Partners in Health (SES), an organisation that has installed microgrids in medical centres in the Peruvian Amazon. He stresses to Dialogue Earth that access to energy is crucial for health, especially for children under five and older adults: “Electricity allows food to be refrigerated and prevents diseases such as food poisoning and diarrhoea, as well as mitigating heatwaves.”
Several studies also link microgrids to poverty and inequality reduction, as they offer cheaper and more reliable electricity. This can bring additional health benefits too, as poverty is often a driver of ill health.
Bracing for warming
Global warming is likely to make power problems worse for people who do not have resilient systems to rely on. Heatwaves are predicted to get more frequent, more intense and longer across Latin America.
In Mexico, where electricity coverage exceeds 99% of the population, heatwaves have already pushed the grid to its limits. In 2024 and 2025, multiple states suffered blackouts when energy demand skyrocketed.
There are two forces coming together: urgency and opportunity. And that combination can accelerate the deployment of microgridsAlejandro Solís Tenorio, an expert in renewable energy at the Autonomous University of Guadalajara
“I had never seen a transmission and generation crisis occurring at the same time in Mexico,” Alejandro Solís Tenorio, an expert in renewable energy at the Autonomous University of Guadalajara (UAG), explains to Dialogue Earth.
In such a scenario, microgrids can prevent critical outages.
As Solís Tenorio points out, “hospitals, cold chains and essential services cannot afford to shut down during a heatwave.” For example, in Mexicali in the north of the country, temperatures exceed 50C in summer and there are constant blackouts. So, there are plans to install solar panels on 150,000 homes by 2030, and to create microgrids in isolated communities. Mexicali’s businesses are also pushing for microgrids.
“There are two forces coming together: urgency and opportunity. And that combination can accelerate the deployment of microgrids,” concludes Solís Tenorio.
In Puerto Rico, more than 48,000 people rely on medical equipment that requires power so they can live independently.
One of these so-called “electro-dependents” is 93-year-old Iluminada Vélez, who lives in Adjuntas and needs an oxygen machine to help her breathe. During heatwaves, her family used to fan her with a cardboard box to keep her from suffocating. Now, her equipment runs without interruption thanks to solar power.
As her son-in-law Jaime says, “without solar energy, she might have died.”
This is the second in a pair of articles about microgrid deployment around the world. You can read the first part here.
