Author(s): Angelo Verzoni. Published on May 16, 2022.

A Revamped ESS Standard

A new edition of NFPA 855 is on the horizon. Here are some of the changes under consideration for 2023.


The 2023 edition of NFPA 855, Standard for the Installation of Stationary Energy Storage Systems, is due out later this year, with debate and voting on any certified amending motions to take place at the 2022 Technical Meeting on June 8 in Boston.

Proposed changes for the new edition, which will be the second-ever version of NFPA 855, include the addition of a scope—an unusual omission from the first edition of NFPA 855 that resulted from utility companies pushing for full exemption from the standard—as well as a new chapter on flywheel energy storage systems and retroactive requirements for non-listed storage systems.

When the first edition of NFPA 855 came out in late 2019, it was perhaps the only NFPA document ever to not include a scope, the section at the beginning of the document explaining what and who the document applies to. The reason for that, explained Christopher Coache, the NFPA staff liaison to NFPA 855, was because utility companies had fought hard for a scope that says they are exempt from all of NFPA 855’s provisions, arguing their own engineering expertise ensures they will do things safely. The NFPA 855 technical committee disagreed, but membership voted in favor of the utility companies’ desire. In any case, an official scope was never published for the standard. That could change in the 2023 edition.

A proposed scope for the new edition does not include a utility exemption, Coache said, but there are dozens of instances throughout the standard where exemptions are given. “The committee has chosen to include carveouts, or exemptions, to utilities for specific requirements,” Coache said. “But the utility companies still want a carte blanche exemption written into the scope. There will certainly be notices of intent to make a motion filed. We’ll see what happens.”

Another, less controversial proposed change would require energy storage system owners to complete a hazard mitigation analysis and potentially implement enhanced safety measures for any systems that aren’t certified to the energy storage system requirements of UL 9540. “If somebody decides to enforce the new edition, and you’ve got battery energy storage systems that aren’t listed, we’re not saying you need to rip out and replace the batteries, but you will need to reevaluate the hazards and provide protection that’s necessary,” Coache said.

The first edition of NFPA 855 included a reserved chapter on flywheel energy storage systems, which generate and store energy using a spinning rotor. The full chapter is expected to be included in the new edition. The chapter would include requirements such as monitoring flywheel bearings for excessive wear and ensuring wheel spinning has stopped before any maintenance, system decommissioning, or relocation occurs.

To learn more about NFPA 855 and to view updates on the progress of the 2023 edition, visit

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