Vieques Microgrid Network 

A rural island community leverages resilient solar+storage to build energy security and combat high energy burdens.

Residential rooftop solar installed in Vieques, Puerto Rico. Credit: Community Through Colors

In September 2017, Category 5 storm Hurricane Maria knocked out 100% of Puerto Rico’s power. Electric service was returned to the main island in under a year; however, the island of Vieques remained disconnected due to significant damage to the underwater distribution cables that delivered power to the island. Even now, with the distribution cables repaired, most residents of Vieques still face severe energy insecurity from high electricity costs (exceeding $0.30 per kWh, double the average in the contiguous states) and near daily brownouts.

In 2019, Community Through Colors (CTC) received a Technical Assistance Fund award from Clean Energy Group to explore solar+storage to support Vieques residents living in single-family homes. CTC chose to prioritize installing resilient power systems at the homes of medically vulnerable residents who relied on electricity to power their medical equipment, including CPAPs, nebulizers, and refrigeration for medication. These residents are especially vulnerable in the event of a power outages as their life-sustaining medical equipment is left inoperable or limited to power reserves. As of Spring 2023, CTC has installed solar+storage at six single-family homes.

During their initial research and community outreach, CTC decided to expand their scope beyond single-family homes to also include emergency response and critical community facilities . Since 2019, more than 10 critical community facilities have received solar+storage.

Solar+storage supported infrastructure in Vieques includes:

• The emergency communications tower: Previously, emergency response was hindered by lack of reliable cell service. Powering the emergency communications tower during grid outages enables emergency response teams to communicate throughout the island more effectively.
• The only fire department on the island of Vieques
• A municipal administration building
• An elderly care center that also serves as food bank
• Multiple resilience hubs and hurricane shelters

Solar+storage systems at both the single-family residences and community facilities have operated through daily brownouts and multiple brief power outages. The systems also remained online during and after the widespread Hurricane Fiona outages in 2022. Most installed battery systems can provide power for between 12 and 72 hours during an outage depending on the system’s size and the critical loads it would support.

Residents and community facilities experience substantial financial benefits for participating. Some participants have seen their bill be reduced by as much as 84% in some cases . CTC is currently working to establish an electricity cooperative to control the microgrid and expand participation options for residents and businesses that are not well-suited to host solar and/or battery storage. This effort is being supported through Clean Energy Groups Resilient Power Leadership Initiative.

Solar+storage installations were funded through fundraising campaigns, grant support, and donations of new or used equipment (including solar panels and batteries). Especially in cases where the solar and storage were donated, the system’s size was determined by available materials and did not always represent optimal sizing. On average, the battery is rated at half the capacity of the solar array, but some batteries can support up to 200% of the solar array’s production.

“Our organization applied for the Technical Assistance Fund to provide Vieques, Puerto Rico equitable access to resilient energy following the devastation of Hurricane Maria. Participation in the fund proved invaluable as it provided the support necessary for us to successfully develop a community solar microgrid plan, reduce energy costs and increase energy efficiency, and promote sustainable practices in our community.” - Oscar Ruiz, President and Executive Director of Community Through Colors