November 1, 2023 TO:
FDS Inspectors and Plan Checkers
FROM:
Hani G. Malki, Sr. Fire Protection Engineer Fire Development Services Section
SUBJECT:
TESLA (Powerwall+ and Powerwall 2) Energy Storage System (ESS) on R3 occupancy building
Effective August 01, 2023, to facilitate the installation of TESLA (Powerwall+ and Powerwall 2) Energy Storage Systems (ESS) on R3 occupancy buildings, Fire Development Services has provided revised guidelines for installers. These guidelines shall supersede all previously issued guidelines. When TESLA (Powerwall+ and Powerwall 2) ESS are installed in accordance with ALL of the following guidelines, an electrical application from LADBS would not need additional Fire Department review. 1. ESS battery unit(s) are for exterior installation(s). 2. Powerwall+ and Powerwall 2 ESS units shall be installed with a minimum side to side separations of 10”. Stacking of Powerwall+ and Powerwall 2 ESS units is allowed when utilizing the manufacturer provided stacking hardware. Separation to any other ESS unit model or manufacturer shall be minimum 3’. 3. ESS unit(s) to be minimum 3’ from any window and door openings (e.g., windows, doors), attic vents, dryer vents, kitchen exhaust, under floor openings, etc.). ● Dryer vents or kitchen exhausts within 3’ of these batteries shall be metal with a functional damper ● Underfloor ventilations within 3' of these batteries are to have metal finned louver screens. ● Underfloor access panels within 3' of these batteries shall have a noncombustible finish (e.g. 26-gauge sheet metal) ● ESS may be installed within 3’ of windows and doors leading into garages when the garage is separated from the dwelling unit living space in accordance with “CRC R302.6”. 4. Surfaces of ESS unit(s) to be not less than 3’ from the main electrical panel. Provide a minimum 5’ clear space on each side of the ESS to any obstructions that extends 18” beyond the wall surface (rain barrels, tool shed, a/c units, hot water tanks, etc…) to ensure hose stream access.
FDS Inspectors and Plan Checkers November 1, 2023 5. ESS disconnect to be no closer than 3’ from ESS. Proper signage(s) shall read “ENERGY STORAGE SYSTEM AC DISCONNECT”. 6. Access pathway(s): one 3’ wide minimum unobstructed pathway (e.g., clearance from air conditioning units, parked cars, rain barrels, trees, heavy vegetation) to access the ESS unit(s) or two 30” unobstructed pathways are provided to access the ESS unit(s) from opposite directions. 7. If equipment is subject to physical damage (e.g., motor vehicles etc.), it shall be protected with an approved barrier system complying with “CRC R328.8.3”. **Provide an elevation diagram (see sample below) and a site plan for all conditions listed above. ** This memo is only applicable to the listed models above and may be modified, superseded, or rescinded at any time without notice.
__________________________________ Hani G. Malki, Sr. Fire Protection Engineer Fire Development Services Section