Turning Retired Batteries into Community Assets
Every year, thousands of hybrid vehicle battery modules are removed from service because they no longer satisfy the demanding performance requirements of automotive use. While many of these modules can be reconditioned and returned to hybrid vehicles through the Green Zone, others no longer meet automotive
standards even though they still retain substantial energy storage capability. Rather than sending these valuable modules directly to recycling, TECRE proposes giving them a second life as community energy storage.
By extending the useful life of retired battery modules, Puerto Rico can create jobs, strengthen energy resilience, reduce waste, and build a practical circular battery economy that benefits both people and the environment.
Many low-income communities in Puerto Rico experience frequent electrical outages. In communities such as the G8 surrounding the Caño Martín Peña, many homes have lightweight galvanized steel roofs that are not suitable for supporting rooftop solar panels. For this reason, the Yellow Zone is designed as a standalone battery backup system rather than a rooftop solar installation.
As the Yellow Zone program is developed and funded, TECRE’s goal is to provide eligible G-8 residents with a fully assembled Community Energy Integrated Battery Assembly (CEIBA, pronounced ‘say-bah’): A battery box that is ready to provide electricity whenever the grid fails.
How CEIBA Backup Power Works
Through the Yellow Zone™, TECRE plans to make subsidized CEIBA units available to residents of the G-8 communities surrounding the Caño Martín Peña. During a grid outage, a CEIBA can support refrigerators, lighting, fans, phone charging, and other essential household loads. When the unit’s performance diminishes, residents simply return their CEIBA to the local reconditioning center and exchange it for a ready-to-use CEIBA containing repurposed, fully reconditioned battery modules.
Each CEIBA contains 42 reconditioned Toyota hybrid nickel-metal hydride (NiMH) battery modules arranged as six parallel strings containing seven modules each. The seven 7.2-volt modules connected in series produce 50.4 volts per string. Connecting six of these strings in parallel within the CEIBA affords up to 1.8 kWh of stored energy. The voltage of each string aligns with the voltage of four lead-acid batteries in series. This allows CEIBA to take advantage of widely available 48-volt-class inverter/charger platforms originally developed for lead-acid systems. Using established power-electronics hardware reduces costs, increases accessibility, and simplifies service.
Creating Community Jobs
✔ Creates skilled local jobs in battery testing, reconditioning, battery pack assembly, inventory management, and mobile battery replacement services.
✔ Provides hands-on technical training that prepares G8 residents for careers in battery technology and renewable energy.
✔ Supports community energy programs by managing battery distribution, exchanges, and residential backup power systems.
✔ Builds lasting local expertise through TECRE’s technical leadership, ongoing training, and long-term community partnerships.
Creating Pathways to Clean Energy Future
✔ Provides hands-on training in battery diagnostic, reconditioning, energy storage and electronics.
✔ Creates living laboratories where students learn through real-world battery reuse and community energy projects.
✔ Connects students with community technicians to develop practical skills while contributing to community resilience.
✔ Builds circular economy knowledge through real-world applications of battery reuse and responsible management.
By connecting proven battery technologies with community needs, TECRE is creating pathways from retired batteries to meaningful economic, educational, and energy opportunities. Every battery repurposed, every skill developed, and every community partnership brings Puerto Rico closer to a Circular Battery Economy™—one where valuable resources create lasting opportunities and strengthen the communities they serve.