This Interpretation of Regulations (IR) clarifies specific code requirements relating to battery energy storage systems (BESS) consisting of prefabricated modular structures not on or inside a building for structural safety and fire life safety reviews. Battery Energy Storage Systems, or BESS, help stabilize electrical grids by providing steady power flow despite fluctuations from inconsistent generation of renewable energy sources and other disruptions. While BESS technology is designed to bolster grid reliability, lithium battery fires at some. An ESS system is a technology that helps supplement renewable energy sources (such as wind and solar), support the country's electrical infrastructure, and can even provide electricity to our homes during a power failure.