Battery Energy Storage Systems (BESS) Best Practices Report

Share Battery Energy Storage Systems (BESS) Best Practices Report on Facebook Share Battery Energy Storage Systems (BESS) Best Practices Report on Twitter Share Battery Energy Storage Systems (BESS) Best Practices Report on Linkedin Email Battery Energy Storage Systems (BESS) Best Practices Report link

The opportunity has concluded. On December 10, 2024, the Board of Supervisors voted to receive the BESS Practices Report and determined that it was best to leave the BESS requirements up to the County Fire Chief.  You can read the document and follow the Board’s positions on the County’s Board of Supervisors page https://file.sandiegocounty.gov/COB/COBPublicView?FileId=39876589

The County of San Diego Fire Protection District has hired a consultant to review the current fire safety standards for BESS, which are large battery systems used to store energy. The goal was to make sure these projects are safe and follow the necessary guidelines to protect people and property. The consultant study found several important requirements that BESS projects need to follow to meet fire safety standards. Here are the main takeaways:

  • Follow Fire Safety Codes: BESS projects must follow all safety recommendations from the National Fire Protection Association (NFPA) and standards in the California Fire Code (CFC).
  • Install Fire Suppression Systems: Each BESS project must include a proper fire suppression system to put out fires if they occur.
  • Keep Safe Distances: BESS projects must be placed at a safe distance from nearby property lines—either 50 feet or 20 feet, depending on the specifics of the project.
  • Create a Fire Safety and Evacuation Plan: Every project must have a plan in place to ensure the safety of people in the event of a fire, including a clear evacuation plan.
  • Model Fire Risks: The study recommends that BESS projects include a detailed analysis of how fire or smoke might spread (called plume modeling) as part of their safety planning.
  • Study Hazards Thoroughly: Projects must include a thorough analysis of potential fire risks, including how to handle fire, alarms, spacing between buildings, and protections against overheating or thermal runaway (when batteries can overheat and catch fire).

In short, the study emphasizes that BESS projects need to take serious precautions to ensure they are built safely and responsibly, with systems in place to prevent and handle fires effectively.

The draft BESS Best Practice Report and the Interim Fire Protection Guidelines for BESS Facilities are now available for your review and feedback. Please send comments via email to Fire@sdcounty.ca.gov or use the form below to share your input.

While this Best Practice Report is one step to creating new standards for BESS applicants to follow, Planning & Development Services will be kicking off an effort to add BESS as a land use within the County's Zoning Ordinance, including zoning and development requirements specifically for BESS in the unincorporated area of the county. This effort is set to kick off in 2025. Please sign up for the email notification list to stay updated on this effort.

Previous Stakeholder Engagement

11/14/24 Webinar on Battery Energy Storage Systems


The County of San Diego Fire Protection District has hired a consultant to review the current fire safety standards for BESS, which are large battery systems used to store energy. The goal was to make sure these projects are safe and follow the necessary guidelines to protect people and property. The consultant study found several important requirements that BESS projects need to follow to meet fire safety standards. Here are the main takeaways:

  • Follow Fire Safety Codes: BESS projects must follow all safety recommendations from the National Fire Protection Association (NFPA) and standards in the California Fire Code (CFC).
  • Install Fire Suppression Systems: Each BESS project must include a proper fire suppression system to put out fires if they occur.
  • Keep Safe Distances: BESS projects must be placed at a safe distance from nearby property lines—either 50 feet or 20 feet, depending on the specifics of the project.
  • Create a Fire Safety and Evacuation Plan: Every project must have a plan in place to ensure the safety of people in the event of a fire, including a clear evacuation plan.
  • Model Fire Risks: The study recommends that BESS projects include a detailed analysis of how fire or smoke might spread (called plume modeling) as part of their safety planning.
  • Study Hazards Thoroughly: Projects must include a thorough analysis of potential fire risks, including how to handle fire, alarms, spacing between buildings, and protections against overheating or thermal runaway (when batteries can overheat and catch fire).

In short, the study emphasizes that BESS projects need to take serious precautions to ensure they are built safely and responsibly, with systems in place to prevent and handle fires effectively.

The draft BESS Best Practice Report and the Interim Fire Protection Guidelines for BESS Facilities are now available for your review and feedback. Please send comments via email to Fire@sdcounty.ca.gov or use the form below to share your input.

While this Best Practice Report is one step to creating new standards for BESS applicants to follow, Planning & Development Services will be kicking off an effort to add BESS as a land use within the County's Zoning Ordinance, including zoning and development requirements specifically for BESS in the unincorporated area of the county. This effort is set to kick off in 2025. Please sign up for the email notification list to stay updated on this effort.

Previous Stakeholder Engagement

11/14/24 Webinar on Battery Energy Storage Systems


The opportunity has concluded. On December 10, 2024, the Board of Supervisors voted to receive the BESS Practices Report and determined that it was best to leave the BESS requirements up to the County Fire Chief.  You can read the document and follow the Board’s positions on the County’s Board of Supervisors page https://file.sandiegocounty.gov/COB/COBPublicView?FileId=39876589

Have a question about the Battery Energy Storage Systems? Ask us. We will get back to you as soon as we can

  • Share Hazard Mitigation Analysis (HMA) Specifics: Are there specific criteria or local factors, like wildfire exposure or community population density, that you would recommend we include in our Hazard Mitigation Analysis to meet county expectations fully? on Facebook Share Hazard Mitigation Analysis (HMA) Specifics: Are there specific criteria or local factors, like wildfire exposure or community population density, that you would recommend we include in our Hazard Mitigation Analysis to meet county expectations fully? on Twitter Share Hazard Mitigation Analysis (HMA) Specifics: Are there specific criteria or local factors, like wildfire exposure or community population density, that you would recommend we include in our Hazard Mitigation Analysis to meet county expectations fully? on Linkedin Email Hazard Mitigation Analysis (HMA) Specifics: Are there specific criteria or local factors, like wildfire exposure or community population density, that you would recommend we include in our Hazard Mitigation Analysis to meet county expectations fully? link

    Hazard Mitigation Analysis (HMA) Specifics: Are there specific criteria or local factors, like wildfire exposure or community population density, that you would recommend we include in our Hazard Mitigation Analysis to meet county expectations fully?

    TT asked 5 months ago

    We'll provide exact guidance on what specifics are required in the Hazard Mitigation Analysis to each project applicant after the 12/10/24 Board of Supervisors hearing.

  • Share Spacing and Fire Containment Requirements: For outdoor BESS installations using LFP batteries with UL 9540A testing, does the county have any specific spacing preferences or barriers beyond the standard 5-10 feet, especially in cases where propagation data may be limited? on Facebook Share Spacing and Fire Containment Requirements: For outdoor BESS installations using LFP batteries with UL 9540A testing, does the county have any specific spacing preferences or barriers beyond the standard 5-10 feet, especially in cases where propagation data may be limited? on Twitter Share Spacing and Fire Containment Requirements: For outdoor BESS installations using LFP batteries with UL 9540A testing, does the county have any specific spacing preferences or barriers beyond the standard 5-10 feet, especially in cases where propagation data may be limited? on Linkedin Email Spacing and Fire Containment Requirements: For outdoor BESS installations using LFP batteries with UL 9540A testing, does the county have any specific spacing preferences or barriers beyond the standard 5-10 feet, especially in cases where propagation data may be limited? link

    Spacing and Fire Containment Requirements: For outdoor BESS installations using LFP batteries with UL 9540A testing, does the county have any specific spacing preferences or barriers beyond the standard 5-10 feet, especially in cases where propagation data may be limited?

    TT asked 5 months ago

    Not at this time, but spacing will be a consideration at the December 10, 2024 Board of Supervisors hearing.

  • Share when there is a problems with the BESS, such as a fire, who is held liable for damages - the BESS? the city? or the County? on Facebook Share when there is a problems with the BESS, such as a fire, who is held liable for damages - the BESS? the city? or the County? on Twitter Share when there is a problems with the BESS, such as a fire, who is held liable for damages - the BESS? the city? or the County? on Linkedin Email when there is a problems with the BESS, such as a fire, who is held liable for damages - the BESS? the city? or the County? link

    when there is a problems with the BESS, such as a fire, who is held liable for damages - the BESS? the city? or the County?

    cg asked 5 months ago

    Investigations are conducted after each event to determine the cause and origin of a fire.  We can't speak to the broad question of liability for any event. County Fire is dedicated to adopting codes and best practices to ensure that fires don't result in damage, which is why we are going through this process.

  • Share Seismic and Structural Compliance Verification: Are there specific seismic design or anchoring requirements for outdoor BESS that the county would like documented beyond ASCE 7-16 standards? on Facebook Share Seismic and Structural Compliance Verification: Are there specific seismic design or anchoring requirements for outdoor BESS that the county would like documented beyond ASCE 7-16 standards? on Twitter Share Seismic and Structural Compliance Verification: Are there specific seismic design or anchoring requirements for outdoor BESS that the county would like documented beyond ASCE 7-16 standards? on Linkedin Email Seismic and Structural Compliance Verification: Are there specific seismic design or anchoring requirements for outdoor BESS that the county would like documented beyond ASCE 7-16 standards? link

    Seismic and Structural Compliance Verification: Are there specific seismic design or anchoring requirements for outdoor BESS that the county would like documented beyond ASCE 7-16 standards?

    TT asked 5 months ago

    None of the projects proposed within the San Diego County Fire Protection District are outdoors.  They are location on conex containers.  They are required to meet all the requirements of the building code.

  • Share Dispersion Modeling Requirements for LFP Batteries: Since a project using LFP batteries with lower toxic emissions, would the county require full dispersion modeling, or are there acceptable alternatives tailored to the lower risk of toxic off-gassing? on Facebook Share Dispersion Modeling Requirements for LFP Batteries: Since a project using LFP batteries with lower toxic emissions, would the county require full dispersion modeling, or are there acceptable alternatives tailored to the lower risk of toxic off-gassing? on Twitter Share Dispersion Modeling Requirements for LFP Batteries: Since a project using LFP batteries with lower toxic emissions, would the county require full dispersion modeling, or are there acceptable alternatives tailored to the lower risk of toxic off-gassing? on Linkedin Email Dispersion Modeling Requirements for LFP Batteries: Since a project using LFP batteries with lower toxic emissions, would the county require full dispersion modeling, or are there acceptable alternatives tailored to the lower risk of toxic off-gassing? link

    Dispersion Modeling Requirements for LFP Batteries: Since a project using LFP batteries with lower toxic emissions, would the county require full dispersion modeling, or are there acceptable alternatives tailored to the lower risk of toxic off-gassing?

    TT asked 5 months ago

    If this type of project as you describe is proposed within San Diego County Fire Protection District, we would require a technical study with plume modeling regardless of the type of battery proposed.

  • Share Emergency Training and Response Coordination with Fire Services: Can the county provide specific guidance on the frequency and scope of emergency response training for facility personnel and local first responders? on Facebook Share Emergency Training and Response Coordination with Fire Services: Can the county provide specific guidance on the frequency and scope of emergency response training for facility personnel and local first responders? on Twitter Share Emergency Training and Response Coordination with Fire Services: Can the county provide specific guidance on the frequency and scope of emergency response training for facility personnel and local first responders? on Linkedin Email Emergency Training and Response Coordination with Fire Services: Can the county provide specific guidance on the frequency and scope of emergency response training for facility personnel and local first responders? link

    Emergency Training and Response Coordination with Fire Services: Can the county provide specific guidance on the frequency and scope of emergency response training for facility personnel and local first responders?

    TT asked 5 months ago

    Sure, when a BESS Facility is near operational, an on-site tour is organized with the operators and the local firefighters to go over the suppression system, operations, access, and several other components.  We also complete pre-fire plans that are available to firefighters if an incident occurs.  These plans show details such as hydrant locations, access, and any special instructions.

  • Share Inspection Frequency and Compliance Expectations: Are there any preferred intervals or additional inspections beyond NFPA recommendations that the county suggests for maintaining compliance with safety standards over time? on Facebook Share Inspection Frequency and Compliance Expectations: Are there any preferred intervals or additional inspections beyond NFPA recommendations that the county suggests for maintaining compliance with safety standards over time? on Twitter Share Inspection Frequency and Compliance Expectations: Are there any preferred intervals or additional inspections beyond NFPA recommendations that the county suggests for maintaining compliance with safety standards over time? on Linkedin Email Inspection Frequency and Compliance Expectations: Are there any preferred intervals or additional inspections beyond NFPA recommendations that the county suggests for maintaining compliance with safety standards over time? link

    Inspection Frequency and Compliance Expectations: Are there any preferred intervals or additional inspections beyond NFPA recommendations that the county suggests for maintaining compliance with safety standards over time?

    TT asked 5 months ago

    Nothing beyond NFPA recommendations.  For the BESS Facilities in San Diego County Fire Protection District, thorough inspections are completed before occupancy is granted and then annually

  • Share Community Engagement and Transparency: Does the county have any suggestions for additional community engagement or information-sharing practices beyond using local publications to keep our neighbors informed? on Facebook Share Community Engagement and Transparency: Does the county have any suggestions for additional community engagement or information-sharing practices beyond using local publications to keep our neighbors informed? on Twitter Share Community Engagement and Transparency: Does the county have any suggestions for additional community engagement or information-sharing practices beyond using local publications to keep our neighbors informed? on Linkedin Email Community Engagement and Transparency: Does the county have any suggestions for additional community engagement or information-sharing practices beyond using local publications to keep our neighbors informed? link

    Community Engagement and Transparency: Does the county have any suggestions for additional community engagement or information-sharing practices beyond using local publications to keep our neighbors informed?

    TT asked 5 months ago

    Related to this BESS Study, we have used the Engage Site successfully to keep the community informed.  If your questions relate to other reasons for engagement we can probably help with other ideas, please contact us at Fire@san.diego.ca.gov

  • Share I work for EVO Power USA, a BESS integrator initiating operations in south OC. We have interests in understanding the regulations and recommendations being implemented in key counties like San Diego, specifically from the battery OEM side of concerns. Eager to set up time with someone directly involved in code development and enforcement. on Facebook Share I work for EVO Power USA, a BESS integrator initiating operations in south OC. We have interests in understanding the regulations and recommendations being implemented in key counties like San Diego, specifically from the battery OEM side of concerns. Eager to set up time with someone directly involved in code development and enforcement. on Twitter Share I work for EVO Power USA, a BESS integrator initiating operations in south OC. We have interests in understanding the regulations and recommendations being implemented in key counties like San Diego, specifically from the battery OEM side of concerns. Eager to set up time with someone directly involved in code development and enforcement. on Linkedin Email I work for EVO Power USA, a BESS integrator initiating operations in south OC. We have interests in understanding the regulations and recommendations being implemented in key counties like San Diego, specifically from the battery OEM side of concerns. Eager to set up time with someone directly involved in code development and enforcement. link

    I work for EVO Power USA, a BESS integrator initiating operations in south OC. We have interests in understanding the regulations and recommendations being implemented in key counties like San Diego, specifically from the battery OEM side of concerns. Eager to set up time with someone directly involved in code development and enforcement.

    Luis Cazares asked 5 months ago

    Please email us at Fire@san.diego.ca.gov, thanks

  • Share If a project has been accepted by the county prior to the September 11, 2024 Supervisor’s meeting, and is already going through a study process by the county, which fire department codes does that project have to adhere to? on Facebook Share If a project has been accepted by the county prior to the September 11, 2024 Supervisor’s meeting, and is already going through a study process by the county, which fire department codes does that project have to adhere to? on Twitter Share If a project has been accepted by the county prior to the September 11, 2024 Supervisor’s meeting, and is already going through a study process by the county, which fire department codes does that project have to adhere to? on Linkedin Email If a project has been accepted by the county prior to the September 11, 2024 Supervisor’s meeting, and is already going through a study process by the county, which fire department codes does that project have to adhere to? link

    If a project has been accepted by the county prior to the September 11, 2024 Supervisor’s meeting, and is already going through a study process by the county, which fire department codes does that project have to adhere to?

    TT asked 5 months ago

    They are required to meet the 2022 California Fire Code and the 2023 San Diego County Fire Code.  Although, the Board of Supervisors may impose interim additional fire code requirements immediately if a hazard is identified.