Fremont, Calif., December 18, 2026 - Trina Storage, a global leader in energy storage, has successfully completed a full-container 5MWh Large-Scale Fire Test (LSFT) of its self-developed Elementa 2 Pro system, conducted under extreme conditions.

The test occurred under the full supervision of internationally recognized third-parties, including TÜV Rheinland and a leading North American fire protection and life-safety engineering firm, Hiller, frequently engaged by authorities having jurisdiction (AHJs), utilities and insurers. The test was executed in accordance using methods aligned with UL 9540A:2025-11, with results intended to support NFPA 855:2026-based system design, permitting and risk evaluation under conditions more stringent than minimum industry test requirements.

The successful completion of this LSFT under rigorous third-party oversight and validation confirms the Elementa 2 Pro’s robust system-level safety performance.

A real-site layout — intensified far beyond test limits

To simulate utility-scale operation while deliberately amplifying thermal challenges, the LSFT was carried out in a full 1:1 site layout with multiple testing conditions escalated beyond standard requirements:

• 10 cm (<4 in) Cabinet spacing: Heat concentration intensified

Containers were arranged back-to-back at only 10 cm, far below the 60 cm standard distance, minimizing heat dissipation and increasing thermal stress.

• Maximum energy configuration: 100% State of change (SOC) full installation

The initiating cabin was ignited with all modules installed and charged to 100% SOC, maximizing thermal runaway. Battery modules in the adjacent rack roof were also fully charged, significantly increasing the risk of propagation.

• Fire suppression disabled: Safety design fully tested without intervention

All automatic suppression and active extinguishing functions remained off throughout the test, requiring the system to rely solely on its structural isolation and engineering-level safety design.

• Pressure-relief panels and ventilation system kept open: Oxygen flow boosted

The pressure-relief panels and ventilation system remained open to intensify oxygen flow, increasing combustion strength and thermal load beyond real-world failure scenarios.

Despite these extreme conditions, Elementa 2 Pro maintained structural stability and controlled thermal behavior, with no observed thermal propagation to adjacent cabinets, demonstrating effective system-level safety design.

Elevating Industry Safety Standards to New Heights

Trina Storage's Elementa 2 Pro integrates self-developed 314Ah high-performance battery cells, coupled with a multi-layered safety architecture and systematic engineering design. With enhanced material upgrades from cell to cabinet level, it delivers comprehensive protection. Throughout the entire test process, the initiating cabinet maintained structural integrity without any collapse, while no thermal propagation occurred in adjacent cabinets. Its system-level thermal insulation and safety protection fully met expected requirements. Testing by the third-party authority Hiller confirmed that the internal cells showed no signs of abnormality.

Additionally, the fire alarm system was continuously issuing alerts until battery shutdown, which is a critical factor for real-site response cycles. The uninterruptible power supply (UPS) within the initiating container remained functional, and the electrical cabinet was preserved intact, validating spatial layout, electrical isolation, and equipment protection strategy. Cell temperatures remained below 43.9°C in the back-to-back container and 23.9°C in the side-by-side container — both far beneath the cell venting point — the system showcased outstanding thermal propagation resistance, significantly surpassing typical safety expectations.

From Field Validation to Grid-Level Operation

This large-scale fire test not only validates resilience under extreme boundary conditions, but also reflects Trina Storage’s commitment to safety-first engineering and system-level innovation.

To date, Trina Storage has delivered over 12GWh globally with no reported thermal runaway or fire propagation incidents across deployed systems. The company has been recognized as a BNEF Tier 1 ESS manufacturer for eight consecutive quarters and named in S&P Global 2025 Tier 1 list for energy storage systems, reinforcing its leadership position in the global energy storage sector.

Trina Storage will continue to push safety technology forward, working with customers, regulators and partners worldwide to build a safer, more resilient, and high-quality clean energy future.

About Trina Storage Solutions U.S.

Trina Storage Solutions U.S., a business unit of Trina Solar U.S. established in 2015, is a leading provider of integrated energy storage solutions. Building on nearly three decades of solar and storage expertise, Trina Storage delivers safe, reliable, and cost-effective systems that accelerate the clean energy transition. To date, Trina has deployed more than 12 GWh of storage capacity worldwide.