Vieques Emergency Management Trailer

Since Hurricane Maria destroyed Puerto Rico’s energy infrastructure in 2017, the small island of Vieques has had an especially difficult time maintaining a reliable power supply.

VIDEO: Vieques Solar Trailer - Open in Vimeo

The island’s only source of electricity is a single under-water cable line that was heavily damaged during Maria. Although power has been restored, the grid is still very vulnerable to any extreme weather or other major disruptions (such as earthquakes that disabled a power plant in Puerto Rico in early 2020) and blackouts are frequent. The Vieques Oficina Municipal para el Mangejo de Emergencias (OMME) office needed to be able to maintain operations through an emergency, without relying on power from the grid.

The Vieques OMME office now has access to resilient power when conducting emergency response; a trailer powered entirely by solar PV and battery storage (solar+storage). The trailer will support the efforts of Vieques OMME in the event of an outage by powering critical loads at the OMME office, acting as a mobile emergency management office in the event of an emergency, or delivering power to critical facilities and equipment throughout the island.

Since February 2020, the trailer has been operational and stationed in a hangar next to the Vieques OMME office. Shortly after its completion, the trailer was deployed to a water pump in Vieques that lost power during major earthquakes in the southern part of Puerto Rico.

With the installation of an inlet plug and transfer switch at the Vieques OMME office, the trailer will be able to back up the main breaker panel of the building and power critical loads including; lighting, 2 mini split heat pumps, 4 desktop computers, and a radio repeater, refrigerator, and coffee maker. While there are currently no estimates as to the direct economic benefits of the solar+storage trailer, it’s anticipated to result in a significant reduction in outage events for the Vieques OMME office. With a resilient power supply from the trailer, OMME can continue operations through an outage and avoid needing to relocate, which can be a time consuming, complicated, and costly effort, especially while navigating an emergency.

The emergency management trailer was developed by Footprint Project in partnership with the Oficina Municipal para el Manejo de Emergencias. Sail Relief provided logistical and installation support and Puerto Rico Science, Technology and Research Trust provided a safe, fenced area to keep the trailer during assembling. Clean Energy Group provided technical support and funded the initial feasibility assessment. The system includes 6 Simpliphi “PHI 3.5” Lithium Ferro Phosphate batteries totaling 21 kilowatt-hours, connected to a 5-kilowatt solar array on the roof of the trailer and a 8-kilowatt inverter. Both the inverter and batteries are mounted to the interior of the trailer frame.

The project benefitted from over $16,000 in donated equipment; Simpliphi donated the batteries and Rent. Solar donated the solar modules. The remaining costs were paid for through grants and donations. The inverter cost $4,800, after a discount, and the custom racking – the most expensive line item of the project – totaled $6,200. Four volunteers spent at least 80 hours assembling the trailer after it arrived in Puerto Rico.

Although the trailer has already proven useful, it’s important to note that the mobile unit wasn’t the first project considered. The initial resilient power project planned for was a permanently installed solar+storage system on the Vieques OMME office. However, due to permitting and municipal approval issues, a permanent installation became increasingly unlikely. By pivoting to a mobile solar+storage system, Footprint was able to sidestep the interconnection and bureaucratic issues that were slowing the process, but still faced challenges. In particular, Footprint pursued a specific, custom trailer design that made it difficult to weld the trailer in Puerto Rico due to capacity limitations and the fact that aluminum, the material used for the frame, is expensive to source Puerto Rico. Ultimately, the frame was shipped from Florida and the solar+storage system was installed in San Juan.