In May 2022, IREC held a ribbon cutting for the first phase of a solar energy microgrid in Castañer, Puerto Rico. The solar microgrid, which includes battery storage, provides a secure and resilient electricity source for vital local businesses that include a popular bakery, post office, ice cream shop, beauty parlor, and barber shop, along with two residences. Notably, “this is Puerto Rico’s only solar energy and storage microgrid that is available for use by a group of businesses,” says Carlos Alberto Velázquez López, IREC’s Program Director for Puerto Rico.

In Castañer, which lost power for six months after Hurricanes Maria and Irma, the new system was put to the test sooner than many would have expected. Nearly five years to the day after the 2017 storms, Hurricane Fiona tore through the island and shut down the electricity grid once again. Fortunately, the microgrid continued to provide electricity without interruption.

“As a true model of energy resilience, the microgrid functioned before, during, and after the passage of Hurricane Fiona,” says C.P. Smith, Executive Director of the Cooperativa Hidroeléctrica de la Montaña, IREC’s local partner in the microgrid project. “The microgrid is up and running right now, providing resilient energy to connected small businesses and residents. This allows Castañer merchants to continue offering essential services to their community despite not having electric service from the government power grid.”

The Long Road to Electric Reliability

Across Puerto Rico, the impact of Hurricane Fiona was devastating. The storm exposed rural communities to catastrophically high levels of rain (higher than two feet in some places), as well as widespread flooding, mudslides that destroyed buildings, and landslides that washed away bridges. Supermarkets threatened to close due to a shortage of backup fuel for diesel generators.  More than a week later, about 40% of households still lacked electricity and 25% lacked running water.

It is sobering to learn that five years after Maria, Puerto Rico still struggles to provide reliable electric services to the more than 3 million American citizens who live there. The electric grid remains fragile and dominated by a few large fossil fuel plants. Most of the reconstruction funds intended to shore up the electricity infrastructure remain unspent. Even under normal circumstances, power outages occur on a routine basis. Meanwhile, electricity keeps getting less affordable: The private electric distributor LUMA has imposed multiple rate increases on consumers in the past year alone.

The one bright spot has been significant growth in renewable energy use, and especially solar and battery storage. While solar still only represents a small part of Puerto Rico’s energy portfolio, growing numbers of households have recognized that solar and storage provide a clean and reliable energy source while locking in affordable electricity rates. There were over 40,000 customers with solar photovoltaic systems as of February 2022, an impressive 76% increase over one year, according to the Puerto Rico Energy Bureau (PREB). And in March, the PREB approved 18 utility-scale solar projects totaling 845 MW, the first of six expected procurement tranches in the next three years.

The Castañer Microgrid: A Model for Puerto Rico

The microgrid approach will be an essential part of this renewable energy transition. Microgrids allow local businesses, organizations, and solar companies to partner with national groups like IREC so the entire community can benefit. In Castañer, IREC worked in partnership with the Cooperativa Hidroeléctrica de Montaña, the University of Puerto Rico — Mayagüez, and the local installation company Borintek. The project was supported by the Puerto Rican Solar Business Accelerator, a program led by IREC and Pathstone Corp. and funded by the U.S. Economic Development Administration.

“One of the advantages of a solar and energy storage microgrid is that the batteries take over when the electricity grid fails,” Velázquez says. Another benefit is that during emergencies, the five local businesses connected to the microgrid become energy resilience centers for the entire community. Residents can access food storage, health services, and other basic security needs.

“Without a doubt, this is an example of the importance of energy resilience for the most vulnerable communities,” adds Smith with the Cooperativa Hidroeléctrica de la Montaña. “It is for that reason that the Cooperativa Hidroeléctrica de la Montaña continues to make efforts to provide cost-effective and resilient energy from renewable sources to communities in the Cordillera Central. We are ready to expand this successful program.”

Velázquez notes several lessons learned including the importance of dialogue, education, and consensus in developing a community microgrid. As Puerto Rico continues to rebuild its electricity network, it will be important to support the design, financing, and technical support for this type of project. Stakeholders will need to identify areas of Puerto Rico that are difficult to access and work with their communities to prioritize solar and storage.

Castañer is one of two planned microgrids that IREC is developing with local partners in Puerto Rico. The second will be in the community of Maricao, with a request for proposal likely to go out this fall. Through previous initiatives, IREC has also worked with organizations such as the Hispanic Federation, Clinton Foundation, and Direct Relief to support the installation of solar panels on federally qualified health centers in rural communities.

IREC looks forward to working on other solar energy projects to support Puerto Rico in the future. Most important, we hope such projects can provide a model for large-scale renewable energy development with public support, so that Puerto Rico can finally build an electric grid that is well equipped to handle the challenges of the 21st century.