The New York City Department of Buildings (DOB) has enacted two new rules for battery energy storage systems (ESS), which enable indoor installations and require peer review for all ESS projects. The rules also modify NFPA 855: Standard for the Installation of Stationary Energy Storage Systems to address the unique challenges of New York City. These updates represent a significant step forward for utility-scale developers, commercial and industrial property owners, and their project partners.
A Rapidly Growing Market
New York State is advancing toward its ambitious target of 6 GW of energy storage capacity by 2030, supported by NYSERDA incentives that are accelerating deployment across residential, commercial, and utility sectors. Installed energy storage capacity in the state has already grown by more than 80% year-over-year, underscoring the importance of regulatory clarity to sustain this growth.
Why New Rules Were Needed
Until now, energy storage systems in New York City were primarily governed by the Fire Code and FDNY Rule 3 RCNY 608-01 (which is limited to outdoor and rooftop systems). The DOB Building Bulletins 2019-002 and 2020-023 provided guidance on filing procedures and zoning for accessory ESS installations; however, they did not define allowable system types, sizes, or locations. The new DOB rules, Title 1 RCNY 101-19 and Title 1 RCNY 3616-07, close that gap.
Clear Pathway for Indoor Energy Storage Systems
The rules establish a clear pathway for indoor energy storage systems that were previously subject to case-by-case approval. The allowable aggregate rated capacity for indoor systems has been increased, supporting larger installations, including dedicated-use buildings specifically designed for ESS. Projects exceeding these capacity limits can still proceed through a Hazard Mitigation Analysis (HMA) and DOB approval, maintaining flexibility for higher-capacity systems.
Independent Peer Review Requirement
All energy storage systems must now undergo an independent peer review by a NYS–licensed professional engineer with expertise in Fire Protection Engineering and energy storage systems and applications. The peer reviewer is responsible for verifying compliance with:
- NYC Construction Codes
- NFPA 855
- UL 9540 listing conditions
- The system’s Certificate of Approval (COA)
Peer reviewers must also confirm that UL 9540A test data has been correctly interpreted and that all site-specific fire and explosion hazards are adequately mitigated.
Other Key Provisions:
- Large-Scale Fire Testing: Required per UL 9540A for all indoor ESS, except valve-regulated or vented lead-acid and nickel-cadmium batteries.
- Flood Protection: ESS must be installed above the Design Flood Elevation (DFE).
- Outdoor/Rooftop Systems: Continue to be regulated under 3 RCNY 608-01.
- Mobile ESS: Additional documentation is required for permit applications.
- Parking Garages: Reduced clearance allowances to adjacent exposures.
- Rooftop Installations: Must maintain FDNY access and exposure clearances.
- Recycled EV Batteries: Prohibited for ESS use.
- NFPA 855 Exclusions: Chapters addressing capacitor and fuel cell ESS were not adopted.
Implications for New York City’s Energy Transition
Together, these DOB rules expand the potential applications of energy storage systems in New York City while introducing added complexity to code compliance through new regulatory requirements.
Questions about how these requirements impact your NYC project? Our team is ready to help. Contact us for more information.