Mobile Solar-Electric Systems with Battery Storage for Remote Communities

Solution Overview

Resilient Power Puerto Rico (RPPR) deployed mobile solar-electric systems with battery storage to remote and underserved communities across Puerto Rico following Hurricane Maria in 2017.[9] The initiative was founded by Puerto Ricans living in New York City, Jonathan Marvel and Cristina Roig, hours after Hurricane Maria made landfall on September 20, 2017.[11][5] This approach targets the most vulnerable communities that were cut off from aid and relief services, providing off-grid renewable electricity to community centers where residents can access power for critical needs during disasters and grid outages.[2][3]

Technical Components

The basic hardware consists of 20 solar panels at 350 watts per panel, generating enough energy to operate a community center with off-the-grid renewable electricity, eliminating the need for fossil fuel-burning generators.[3] The installations include two Tesla Powerwall batteries, one for backup, each capable of supplying 5 to 6 kWh.[10] These batteries are super-efficient, occupy very little space, and hang on existing block walls to preserve space for community activities.[10] The systems provide power for refrigeration, lights, fans, and charging stations for cell phones and other small electronic devices.[2] RPPR studied the systems that survived Hurricane Maria and determined optimal construction methods, including upgrading bolt diameter from ¼ inch to ⅜ inch, using specific racking systems, and building small parapets or knee walls around the panels.[6] The organization also developed a mobile emergency management trailer featuring 6 SimpliPhi 'PHI 3.5' Lithium Ferro Phosphate batteries totaling 21 kilowatt-hours, connected to a 5-kilowatt solar array on the roof and an 8-kilowatt inverter.[8] After Hurricane Ida in August 2021, this trailer was outfitted with additional solar panels stored inside that could be deployed on the ground to increase capacity from 5kW initially to roughly 20kW.[8]

Implementation Details

RPPR completed 28 community solar-storage systems installations across the island in the first 11 months of operation, with 38 more in the works.[7] In the first year, the organization raised money for 25 solar hubs, largely from the diaspora of Puerto Ricans living in New York and Silicon Valley, and that wave of 25 was almost finished.[3] The initiative received grants of $625,000 to construct 25 of a planned 100 small, commercial-scale solar arrays.[10] RPPR's Community Solar Energy Initiative (CSEI) deployed 30 solar energy systems to community centers across 22 municipalities in Puerto Rico, including Vieques and Culebra.[11] The organization partnered with community leaders to assess critical energy needs and identify sites where solar energy systems would generate the greatest impact in communities most impacted by Hurricane Maria.[11] CSEI facilitated the donation of over 983 solar panels to 30 community groups island-wide as of September 2019.[11] The organization initially aimed to bring solar power to 100 sites in 100 days, but limited resources—namely, a lack of access to necessary equipment—hindered progress.[6] The island's limited retail solar infrastructure made it difficult to buy batteries and panels due to very limited availability and long wait times.[6] RPPR established a warehouse in the small inland city of Caguas to serve as an office, workshop, and educational venue for people to learn about solar.[6] Key partners include BoxPower, Sunrun, Direct Relief, Blue Planet Energy, SimpliPhi Power, Sonnen, and multiple solar equipment manufacturers and foundations.[2] The emergency management trailer was developed by Footprint Project in partnership with the Oficina Municipal para el Manejo de Emergencias, with Sail Relief providing logistical and installation support and Puerto Rico Science, Technology and Research Trust providing a safe, fenced area during assembly.[8] The trailer frame was shipped from Florida and the solar+storage system was installed in San Juan because aluminum was expensive to source in Puerto Rico and there were capacity limitations for welding the trailer locally.[8] Four volunteers spent at least 80 hours assembling the trailer after it arrived in Puerto Rico.[8] The inverter cost $4,800 after a discount, and the custom racking totaled $6,200, which was the most expensive line item of the project.[8] The project benefitted from over $16,000 in donated equipment, with SimpliPhi donating the batteries and Rent.Solar donating the solar modules.[8]

Benefits and Impacts

After Hurricane Fiona arrived on September 18, 2022, community members found access to clean water, food, and hygiene supplies at the Resilience Hubs, with power from solar panels and large batteries which powered wifi, charging stations, and refrigeration for medication and essential items.[1] These Resilience Hubs are prepared to respond in any disaster and can support approximately 2,000 people in each community.[1] The high-density informal neighborhoods served by the hubs are communities of two, three, or four thousand people that can be serviced with one solar hub.[3] More than two weeks after Hurricane Fiona, 10% of potable water customers were without access to drinking water, and about 30% of Puerto Ricans (266,000 people) were still without power, demonstrating the critical need for resilient power systems.[1] The solar systems pay for themselves in about five years based on the electricity being produced offset against the cost of that electricity.[3] The Vieques Emergency Management Trailer has been utilized by the Vieques emergency management office since 2020.[4] The trailer was operational and used through the outage in Vieques after Hurricane Fiona.[4] 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.[8] During significant island-wide outages, the trailer is generally stationed at the Vieques OMME office to support emergency operations and communications for state and municipal police, firefighters, paramedics and other first responders.[8] The trailer can back up the main breaker panel of the Vieques OMME office building and power critical loads including lighting, 2 mini split heat pumps, 4 desktop computers, a radio repeater, refrigerator, and coffee maker.[8] The solar arrays are not enough to run an air conditioner all day, but will run water filters, pumps, and charging stations for phones and radios.[10]

Climate Adaptation Relevance

Hurricane Maria made landfall in Puerto Rico on September 20, 2017, as a Category 4 storm, causing widespread devastation and leaving the entire island without power.[2] The Puerto Rico Electric Power Authority (PREPA) estimated that it could take up to a year to restore power to the entire island following Hurricane Maria.[2] Hurricane Fiona made landfall in Puerto Rico on September 18, 2022, deluging the island with upwards of 30 inches of rain within 24 hours and leaving all residents without electricity.[1] The mobile solar-electric systems provide critical resilience infrastructure that enables communities to maintain power for essential services during hurricanes, extreme precipitation events, and grid failures that increasingly threaten Puerto Rico's vulnerable populations.[1][2]

Business Analysis

RPPR's three-phase strategy includes relief hubs for the hardest hit and most remote communities, 100 mobile solar kits distributed one each to the 78 municipalities and multiple neighborhoods in bigger municipalities, and ultimately solar electric energy for every household on the island.[5] The organization's goal is ultimately to have 200 community centers operating with solar panels and batteries to produce and store power simultaneously.[3] The initiative targets poor people and those in greatest need, allowing the last in line to get power on a decentralized basis.[3] RPPR partnered with Rocky Mountain Institute (RMI) to launch The Puerto Rico Renewable Microgrid Program, a capacity building program aimed at increasing communities' capacity to assess and address critical energy needs.[11] Through the CSEI program, RPPR led multiple community-focused workshops on solar energy in Puerto Rico and collaborated with over 15 academic programs in the United States researching topics in island resilience and sustainability.[11] Mercy Corps supplied 17 Resilience Hubs with solar energy, potable water storage, communication systems, and emergency kits, and has been present in Puerto Rico since the Hurricane Maria emergency in 2017.[1] In the four months before Hurricane Fiona, Mercy Corps worked closely with Resilience Hub partners and reached one million people across the region through a disaster preparedness campaign.[1] The organization used a planning study done about 25 years ago by planner Lucilla Fuller Marvel to identify the island's informal communities, which researched and documented who was living where for the first time in the island's history.[3] RPPR planned to install 100 panels on top of the warehouse in Caguas to operate off the grid and offer that as a prototype.[6] Clean Energy Group provided technical support and funded the initial feasibility assessment for the emergency management trailer.[8] The initial resilient power project planned for Vieques was a permanently installed solar+storage system on the OMME office, but due to permitting and municipal approval issues, a permanent installation became increasingly unlikely, leading to the pivot to a mobile solar+storage system that sidestepped interconnection and bureaucratic issues.[8]