The successful test demonstrated that SolBank 3.0 meets key fire safety criteria by containing thermal events within a single enclosure, providing enhanced safety assurance for utility-scale deployments.

Canadian Solar Inc. (the "Company" or "Canadian Solar") (NASDAQ: CSIQ) today announced that e-STORAGE, which is part of the Company's majority-owned subsidiary CSI Solar Co., Ltd. ("CSI Solar"), has successfully completed Large-Scale Fire Testing (LSFT) for its SolBank 3.0 energy storage system. The successful test demonstrated that SolBank 3.0 meets key fire safety criteria by containing thermal events within a single enclosure, providing enhanced safety assurance for utility-scale deployments.

The test was conducted under the CSA C-800:25 §9.7 Large-Scale Fire Testing (LSFT) protocol—a rigorous, industry-recognized standard used to evaluate how a fully developed fire condition inside the enclosure of an initiating BESS unit affects propagation risk between adjacent enclosures. During the test, all doors, louvers, and structural elements on target units remained closed and intact throughout the event. The protocol is in compliance with key safety objectives outlined in NFPA 855, such as preventing cascading thermal events and containing fire within a single unit.

During the test, e-STORAGE's SolBank 3.0 energy storage system showed no fire propagation to target units and successfully passed the LSFT, confirming the robustness of SolBank 3.0's passive fire containment design.

The test was witnessed and independently verified by both CSA Group, the testing agency, and Energy Safety Response Group (ESRG), a fire safety consultant.

Josh Dinaburg, Fire Test Specialist at CSA Group, commented, "Key stakeholders in the energy storage industry have raised justifiable concerns about the ability of BESS to limit the spread of fire between units without relying on complex extinguishing systems or putting first responders at risk. The e-STORAGE system demonstrated that an aggressive fire consuming all available fuel in one unit does not ignite new fires and spread to adjacent units. This is critical performance data for the end-users and site managers, first responders, insurance adjusters, and the community at large where these systems may be installed."

Colin Parkin, President of e-STORAGE, stated, "Successfully completing the Large-Scale Fire Testing reinforces our high standard on system safety. At the same time, it once again positions e-STORAGE as a leader in delivering safe, scalable energy storage solutions—across products, projects, and markets—and our continued commitment to go beyond industry standards for operation safety."

About Canadian Solar Inc.

Canadian Solar is one of the world's largest solar technology and renewable energy companies. Founded in 2001 and headquartered in Kitchener, Ontario, the Company is a leading manufacturer of solar photovoltaic modules; provider of solar energy and battery energy storage solutions; and developer, owner, and operator of utility-scale solar power and battery energy storage projects. Over the past 24 years, Canadian Solar has successfully delivered nearly 157 GW of premium-quality, solar photovoltaic modules to customers across the world. Through its subsidiary e-STORAGE, Canadian Solar has shipped over 11 GWh of battery energy storage solutions to global markets as of March 31, 2025, boasting a $3.2 billion contracted backlog as of March 31, 2025. Since entering the project development business in 2010, Canadian Solar has developed, built, and connected approximately 11.6 GWp of solar power projects and 4.5 GWh of battery energy storage projects globally. Its geographically diversified project development pipeline includes 27 GWp of solar and 76 GWh of battery energy storage capacity in various stages of development. Canadian Solar is one of the most bankable companies in the solar and renewable energy industry, having been publicly listed on the NASDAQ since 2006. For additional information about the Company, follow Canadian Solar on LinkedIn or visit www.canadiansolar.com.

About e-STORAGE

e-STORAGE is a subsidiary of Canadian Solar and a leading company specializing in designing, manufacturing, and integrating battery energy storage systems for utility-scale applications. e-STORAGE offers proprietary battery energy storage solutions, comprehensive EPC services, and innovative solutions aimed at improving grid operations. Currently, e-STORAGE operates two fully automated, state-of-the-art manufacturing facilities with an annual battery production capacity of 20 GWh. For more info, please refer to the Media&PR section of www.csestorage.com and follow our LinkedIn page.