CRC · California Residential Code
Energy Storage Systems (ESS), Generators & Backup Power
This hub orients users to CRC Section R330 and the coordinated Fire, Building and Energy Code rules that govern residential energy storage, generators and backup power.
Last reviewed: July 6, 2026
Overview
This hub covers California Residential Code (CRC) provisions that govern the installation, location, sizing and safety of residential energy storage systems (ESS), plus related requirements for stationary engines, generators and backup power. Key CRC provisions include Section R330 (Energy Storage Systems), which sets listing, installation, location and per‑unit/aggregate energy limits (see §R330.1 and §R330.5) . Stationary engine/generator topics for residences are addressed in adjacent CRC sections (for example R331) and are coordinated with the California Building and Fire Codes for equipment, fuel‑line protection and transfer/automatic load‑transfer requirements .
Because ESS and backup generators pose fire, electrical and life‑safety risks, the CRC works together with the California Fire Code (Chapter 12, especially §1207 for electrical ESS and §1203 for emergency/standby power) and the California Building Code (emergency/standby provisions) to require listed equipment, permits, separation, disconnects, working clearances and commissioning where applicable . The Energy Code (Title 24) also affects BESS sizing and integration with on‑site PV systems, so designs must satisfy both the CRC/Fire/Building Code safety rules and the Energy Code performance or prescriptive requirements . Finally, many ESS installations require a construction permit under the Fire Code (see §105.6.6) and retrofit/replacement work is subject to specific commissioning and documentation rules .
In this section
- What electrical installation and inverter listing requirements apply to residential energy storage systems (ESS)?
- What fire detection and alarm provisions apply when ESS are installed in dwellings?
- When is impact protection required for ESS and what are garage placement rules?
- Where does the CRC address stationary engine generators and fuel cell power systems?
Code references
Grounded in the retrieved California Residential Code — click a citation to read the verbatim passage:
CRC § 3.6 High relevance — show source text
DC wiring shall be installed in_ metallic conduit or raceways when located within enclosed spaces in a building. Conduit shall run along the bottom of load bearing members.
SECTION R330—ENERGY STORAGE SYSTEMS
R330.1 General. Energy storage systems (ESS) shall comply with the provisions of this section.
Exceptions:
- ESS listed and labeled for use in habitable spaces, in accordance with UL 9540 and where installed in accordance with the listing, the manufacturer’s instructions and the California Electrical Code.
- ESS less than 1 kWh (3.6 megajoules).
R330.2 Equipment listings. Energy storage systems (ESS) shall be listed and labeled in accordance with UL 9540.
Exception: Where approved, repurposed unlisted battery systems from electric vehicles are allowed to be installed outdoors or in detached sheds located not less than 5 feet (1524 mm) from exterior walls, property lines and public ways.
R330.3 Installation. ESS shall be installed in accordance with the manufacturer’s instructions and their listing.
R330.3.1 Spacing. Individual units shall be separated from each other by not less than 3 feet (914 mm) except where other separation distances are specified by the ESS listing and the manufacturer’s installation instructions.
R330.4 Locations. ESS shall be installed only in the following locations:
Detached garages and detached accessory structures.
Attached garages separated from the dwelling unit living space in accordance with Section R302.6.
Outdoors or on the exterior side of exterior walls located not less than 3 feet (914 mm) from doors and windows directly entering the dwelling unit, except where smaller separation distances are permitted by the UL 9540 listing and manufacturer’s installation instructions.
Enclosed utility closets, basements, storage or utility spaces within dwelling units with finished or noncombustible walls and ceilings. Walls and ceilings of unfinished wood-framed construction shall be provided with not less than [5] / 8 -inch (15.9 mm) Type X gypsum wallboard. Openings into the dwelling shall be equipped with solid wood doors not less than 1 [3] / 8 inches (35 mm) in thickness, solid or honeycomb-core steel doors not less than 1 [3] / 8 inches (35 mm) in thickness, or doors with a 20-minute fire protection rating. Doors shall be self-latching and equipped with a self-closing or an automatic-closing device. Penetrations through the required gypsum wallboard into the dwelling shall be protected as required by Section R302.11, Item 4.
� ESS shall not be installed in sleeping rooms, or closets or spaces opening directly into sleeping rooms.
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BUILDING PLANNING
R330.5 Energy ratings. Individual ESS units shall have a maximum rating of 20 kWh. The ratings of the ESS in each location shall not exceed the ratings in Table R330.5. The total aggregate ratings of ESS on the property shall not exceed 600 kWh.
ESS installations exceeding the permitted individual or aggregate ratings shall be installed in accordance with Section 1207 of the California Fire Code.
|TABLE R330.
CRC § 8.1 Medium relevance — show source text
R329.8 Ground-mounted photovoltaic (PV) panel systems. Ground-mounted photovoltaic (PV) panel systems shall be designed and installed in accordance with Section R301.
R329.8.1 Fire separation distances. Ground-mounted photovoltaic systems shall be subject to the fire separation distance requirements determined by the enforcing agency.
R329.8.2 Ground-mounted photovoltaic arrays. Ground mounted photovoltaic arrays shall comply with this section and the Cali- fornia Electrical Code. Setback requirements shall not apply to ground-mounted, free-standing photovoltaic arrays. A clear, brush- free area of 10 feet (3048 mm) shall be required for ground-mounted photovoltaic arrays.
R329.8.3 Locations of DC conductors. Conduit, wiring systems and raceways for photovoltaic circuits shall be located as close as possible to the ridge or hip or valley and from the hip or valley as directly as possible to an outside wall to reduce trip hazards and maximize ventilation opportunities. Conduit runs between sub arrays and to DC combiner boxes shall be installed in a manner that minimizes the total amount of conduit on the roof by taking the shortest path from the array to the DC combiner box. The DC combiner boxes shall be located such that conduit runs are minimized in the pathways between arrays. DC wiring shall be installed in metallic conduit or raceways when located within enclosed spaces in a building. Conduit shall run along the bottom of load bearing members.
SECTION R330—ENERGY STORAGE SYSTEMS
R330.1 General. Energy storage systems (ESS) shall comply with the provisions of this section.
Exceptions:
- ESS listed and labeled for use in habitable spaces, in accordance with UL 9540 and where installed in accordance with the listing, the manufacturer’s instructions and the California Electrical Code.
- ESS less than 1 kWh (3.6 megajoules).
R330.2 Equipment listings. Energy storage systems (ESS) shall be listed and labeled in accordance with UL 9540.
Exception: Where approved, repurposed unlisted battery systems from electric vehicles are allowed to be installed outdoors or in detached sheds located not less than 5 feet (1524 mm) from exterior walls, property lines and public ways.
R330.3 Installation. ESS shall be installed in accordance with the manufacturer’s instructions and their listing.
R330.3.1 Spacing. Individual units shall be separated from each other by not less than 3 feet (914 mm) except where other separation distances are specified by the ESS listing and the manufacturer’s installation instructions.
R330.4 Locations. ESS shall be installed only in the following locations:
- Detached garages and detached accessory structures.
- Attached garages separated from the dwelling unit living space in accordance with Section R302.6.
- Outdoors or on the exterior side of exterior walls located not less than 3 feet (914 mm) from doors and windows directly entering the dwelling unit, except where smaller separation distances are permitted by the UL 9540 listing and manufacturer’s installation instructions.
CRC § 1206.13 Medium relevance — show source text
1206.13 Group R-3 and R-4 fuel cell vehicle energy storage system use. The temporary use of the dwelling unit owner or occupant’s fuel cell-powered electric vehicle to power a Group R-3 or R-4 dwelling while parked in an attached or detached garage or outside shall comply with the vehicle manufacturer’s instructions and the California Electrical Code .
SECTION 1207—ELECTRICAL ENERGY STORAGE SYSTEMS (ESS)
1207.1 General. The provisions in this section are applicable to stationary and mobile electrical energy storage systems (ESS).
Exception: ESS in Group R-3 and R-4 occupancies shall only be required to comply with Section 1207.11 except where Section 1207.11.4 requires compliance with Sections 1207.1 through 1207.9.
1207.1.1 Utilities and industrial applications. This section shall not apply to capacitors and capacitor equipment for electric utilities and industrial facilities used in applications such as flexible AC transmission (FACTS) devices, filter capacitor banks, power factor correction, and standalone capacitor banks for voltage correction and stabilization. (Material based on NFPA 855 2023 Ed.)
1207.1.2 Mobile ESS. Mobile ESS deployed at an electric utility substation or generation facility for 90 days or less shall not add to the threshold values in Table 1207.1.3 for the stationary ESS installation if both of the following conditions apply:
- The mobile ESS complies with Section 1207.10.
- The mobile ESS is being used only during periods in which the facility’s stationary ESS is being tested, repaired, retrofitted or replaced. (Material based on NFPA 855 2023 Ed.)
1207.1.3 Scope. ESS having capacities exceeding the values shown in Table 1207.1.3 shall comply with this section. (Material based on NFPA 855 2023 Ed.)
TABLE 1207.1.3—ENERGY STORAGE SYSTEM (ESS) THRESHOLD QUANTITIES Col2 TECHNOLOGY ENERGY CAPACITYa Capacitor ESS 3 kWh Flow batteriesb 20 kWh Lead-acid batteries, all types 70 kWhc Lithium-ion batteries 20 kWh Nickel-cadmium (Ni-Cd), nickel metal hydride (Ni-MH) and nickel zinc (Ni-Zn) batteries 70 kWh Nonelectrochemical ESSd 70 kWh Other battery technologies 10 kWh Other electrochemical ESS technologies 3 kWh Sodium nickel chloride batteries 70 kWh Zinc manganese dioxide batteries (Zn-MnO2) 70 kWh For SI: 1 kilowatt hour = 3.6 megajoules.
a. Energy capacity is the total energy capable of being stored (nameplate rating), not the usable energy rating. For units rated in amp-hours, kWh shall equal rated voltage
times amp-hour rating divided by 1,000.
b. Shall include vanadium, zinc-bromine, polysulfide-bromide and other flowing electrolyte-type technologies.
c. Fifty gallons of lead-acid battery electrolyte shall be considered equivalent to 70 kWh.
d. Covers nonelectrochemical technologies such as flywheel and thermal ESS.For SI: 1 kilowatt hour = 3.6 megajoules.
a. Energy capacity is the total energy capable of being stored (nameplate rating), not the usable energy rating.CRC § 12-2 Medium relevance — show source text
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12 ENERGY SYSTEMS
User notes:
About this chapter: Chapter 12 was added to address the current energy systems found in this code, and is provided for the introduction of a wide range of systems to generate and store energy in, on and adjacent to buildings and facilities. The expansion of such energy systems is related to meeting today’s energy, environmental and economic challenges. Ensuring appropriate criteria to address the safety of such systems in building and fire codes is an important part of protecting the public at large, building occupants and emergency responders. More specifically, this chapter addresses standby and emergency power, portable generators, photovoltaic systems, fuel cell energy systems and energy storage systems.
SECTION 1201—GENERAL
1201.1 Scope. The provisions of this chapter shall apply to the installation, operation, maintenance, repair, retrofitting, testing, commissioning and decommissioning of energy systems used for generating or storing energy, including but not limited to energy storage systems under the exclusive control of an electric utility or lawfully designated agency. It shall not apply to equipment associated with the generation, control, transformation, transmission, or distribution of energy installations that is under the exclusive control of an electric utility or lawfully designated agency. Energy storage systems regulated by Section 1207 shall comply with this chapter, as appropriate, and NFPA 855.
1201.2 Electrical wiring and equipment. Electrical wiring and equipment used in connection with energy systems shall be installed and maintained in accordance with this chapter, Section 603 and the California Electrical Code.
1201.3 Mixed system installation. Where mixed systems are approved, the aggregate nameplate kWh energy of all energy storage systems in a fire area shall not exceed the maximum quantity specified for any of the energy systems in this chapter. Where required by the fire code official, a hazard mitigation analysis shall be provided and approved in accordance with Section 104.2.2 to evaluate any potential adverse interaction between the various energy systems and technologies.
SECTION 1202—DEFINITIONS
1202.1 Definitions. The following terms are defined in Chapter 2:
BATTERY SYSTEM, STATIONARY STORAGE.
BATTERY TYPES.
CAPACITOR ENERGY STORAGE SYSTEM.
CRITICAL CIRCUIT.
EMERGENCY POWER SYSTEM.
ENERGY STORAGE MANAGEMENT SYSTEMS.
ENERGY STORAGE SYSTEM (ESS).
ENERGY STORAGE SYSTEM, ELECTROCHEMICAL.
ENERGY STORAGE SYSTEM, MOBILE.
ENERGY STORAGE SYSTEM, WALK-IN UNIT.
ENERGY STORAGE SYSTEM CABINET.
ENERGY STORAGE SYSTEM COMMISSIONING.
ENERGY STORAGE SYSTEM DECOMMISSIONING.
FUEL CELL POWER SYSTEM, STATIONARY.
PORTABLE GENERATOR.
STANDBY POWER SYSTEM.
SECTION 1203—EMERGENCY AND STANDBY POWER SYSTEMS
1203.1 General. Emergency power systems and standby power systems required by this code or the California Building Code shall comply with Sections 1203.1.1 through 1203.1.9.
1203.1.1 Stationary generators. Stationary emergency and standby power generators required by this code shall be listed in accordance with UL 2200.
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CRC § 12-3 Medium relevance — show source text
1202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-3
1203 Emergency and Standby Power Systems. . . . . . . . . 12-3 1204 Portable Generators . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-6
1205 Solar Photovoltaic Power Systems . . . . . . . . . . . . . . 12-6 1206 Stationary Fuel Cell Power Systems . . . . . . . . . . . . . 12-9 1207 Electrical Energy Storage Systems (ESS) . . . . . . . .12-10
CHAPTERS 13–19 RESERVED . . . . . . . . . . . . . . . . . . . . . . .13-1
CHAPTER 20 AVIATION FACILITIES. . . . . . . . . . . . . . . . . . .20-3
2001 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-3
2002 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-3
2003 General Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-3
2004 Aircraft Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . 20-3
2005 Portable Fire Extinguishers . . . . . . . . . . . . . . . . . . . . . 20-4 2006 Aircraft Fueling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-4 2007 Helistops and Heliports . . . . . . . . . . . . . . . . . . . . . . . . 20-9
CHAPTER 21 DRY CLEANING . . . . . . . . . . . . . . . . . . . . . . . .21-3
2101 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-3
2102 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-3
2103 Classifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-3
CRC § 1201.3 Medium relevance — show source text
1201.3 Mixed system installation. Where mixed systems are approved, the aggregate nameplate kWh energy of all energy storage systems in a fire area shall not exceed the maximum quantity specified for any of the energy systems in this chapter. Where required by the fire code official, a hazard mitigation analysis shall be provided and approved in accordance with Section 104.2.2 to evaluate any potential adverse interaction between the various energy systems and technologies.
SECTION 1202—DEFINITIONS
1202.1 Definitions. The following terms are defined in Chapter 2:
BATTERY SYSTEM, STATIONARY STORAGE.
BATTERY TYPES.
CAPACITOR ENERGY STORAGE SYSTEM.
CRITICAL CIRCUIT.
EMERGENCY POWER SYSTEM.
ENERGY STORAGE MANAGEMENT SYSTEMS.
ENERGY STORAGE SYSTEM (ESS).
ENERGY STORAGE SYSTEM, ELECTROCHEMICAL.
ENERGY STORAGE SYSTEM, MOBILE.
ENERGY STORAGE SYSTEM, WALK-IN UNIT.
ENERGY STORAGE SYSTEM CABINET.
ENERGY STORAGE SYSTEM COMMISSIONING.
ENERGY STORAGE SYSTEM DECOMMISSIONING.
FUEL CELL POWER SYSTEM, STATIONARY.
PORTABLE GENERATOR.
STANDBY POWER SYSTEM.
SECTION 1203—EMERGENCY AND STANDBY POWER SYSTEMS
1203.1 General. Emergency power systems and standby power systems required by this code or the California Building Code shall comply with Sections 1203.1.1 through 1203.1.9.
1203.1.1 Stationary generators. Stationary emergency and standby power generators required by this code shall be listed in accordance with UL 2200.
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ENERGY SYSTEMS
1203.1.2 Fuel line piping protection. Fuel lines supplying a generator set inside a high-rise building or new Group I-2 occupancy having occupied floors located more than 75 feet above the lowest level of fire department vehicle access shall be separated from areas of the building other than the room the generator is located in by one of the following methods:
A fire-resistant pipe-protection system that has been tested in accordance with UL 1489. The system shall be installed as tested and in accordance with the manufacturer’s installation instructions, and shall have a rating of not less than 2 hours. Where the building is protected throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1, the required rating shall be reduced to 1 hour.
An assembly that has a fire-resistance rating of not less than 2 hours. Where the building is protected throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1, the required fire-resistance rating shall be reduced to 1 hour.
Other approved methods.
1203.1.3 Installation. Emergency power systems and standby power systems shall be installed in accordance with the California Building Code, the California Electrical Code, NFPA 110 and NFPA 111.
1203.1.3.1 Combustion engines and gas turbines. The installation of combustion engines and gas turbines shall be in accor- dance with California Building Code Section 442 and NFPA 37.
CRC § 907.2.3 Medium relevance — show source text
Early Suppression Fast-Response Sprinkler (ESFR) (see Automatic Sprinklers) Education Occupancy (Group E) 203 Alarms and detection 907.2.3 Means of egress Aisles 1018.2, 1018.5 Corridors 1020.3, 1020.2 Locking 1010.2.12, 1010.2.7 Panic hardware 1010.2.8
Stairways, exit access 1019 Travel distance 1017.2, 1006.3.3,
1006.2.1
Sprinklers 903.2.3 Egress (see Means of Egress) Electrical Equipment 603 Aviation facilities 2006.14 Dust-producing machines 5906.5.5 Signs 603.4.1, 1207.4.8 Work space and clearance 603.4 Workstations in HPM facilities
2703.7.2
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INDEX
Energy Storage System (ESS) 202, 1207 Cabinets 1207.4.10, 1207.4.8, 1207.6.3 Commissioning, decommissioning, operation and maintenance 202, 1207.2
Fire remediation 1207.1.8 Hazard mitigation analysis 1207.1.6 Large-scale fire test 1207.1.7 Mobile ESS 202, 1207.1, 1207.1.2,
1207.10 Residential (R-3 and R-4) 1207.11 Stationary ESS 202, 1207 Walk-in units 202, 1207.1.7, 1207.4.12, 1207.4.6, 1207.4.8, 1207.4.9, 1207.5.2, 1207.5.2.1, 1207.5.4, 1207.5.5, 1207.5.6, 1207.6.1, 1207.6.3, 1207.9.4 Energy Systems Chapter 12, 1201.1, 1201.2 Electrical energy storage systems 1201.3, 1207 Emergency and standby power systems 1203
Permits 105.5.14, 105.6.10, 105.6.21,
105.6.6 Portable generators 1204, 3309 Solar and photovoltaic systems 1205 Stationary fuel cell power systems 1206 Entry, Right of 104.4 Equipment, Fueled 313 Equipment Platform Defined 202
Guards required 1015.2 Escalator Openings (see Floor Openings and Shafts) Escape Openings 1031 ESFR Sprinklers (see Automatic Sprinklers) Ethylene Gas 2503
Generators 2506
CRC § 170.1 Medium relevance — show source text
A. The Efficiency LSC energy is the sum of the LSC energy for space-conditioning, water heating, mechanical ventilation, lighting and the self-utilization credit. B. The Total LSC energy is the sum of the Efficiency LSC energy and LSC energy from the photovoltaic system, battery energy storage systems (BESS), and demand flexibility. 2. Source energy. The source energy budget is determined by applying the mandatory and prescriptive requirements of the standard design, except with a consumer gas or propane water heater, to the proposed design building.
Exception to Section 170.1(a): A community shared solar electric generation system, or other renewable electric generation system, and/or community shared BESS, that provides dedicated power, utility energy reduction credits or payments for energy bill reductions to the permitted building and is approved by the Energy Commission as specified in Title 24, Part 1, Section 10-115, may offset part or all of the solar electric generation system or BESS LSC energy required to comply with the standards, as calculated according to methods established by the Commission in the Nonresidential ACM Reference Manual.
(b) Compliance demonstration requirements for performance standards.
- Certificate of Compliance and Application for a Building Permit. The application for a building permit shall include documentation pursuant to Sections 10-103(a)1 and 10-103(a)2 that demonstrates, using an approved calculation method, that the building has been designed so that its source energy and LSC energy consumption do not exceed the standard design energy budgets for the applicable climate zone.
- Field verification of individual dwelling unit systems. When performance of installed features, materials, components, manufactured devices or systems above the minimum specified in Section 170.2 is necessary for the building to comply with Section 170.1, or is necessary to achieve a more stringent local ordinance, field verification shall be performed in accordance with the applicable requirements in the following subsections, and the results of the verification(s) shall be documented on applicable Certificates of Installation pursuant to Section 10-103(a)3 and applicable Certificates of Verification pursuant to Section 10-103(a)5. A. EER2/SEER2/CEER/HSPF2 Rating. When performance compliance requires installation of a space-conditioning system with a rating that is greater than the minimum rating required by Table 170.2-K or specified for the standard
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MULTIFAMILY BUILDINGS—PERFORMANCE AND PRESCRIPTIVE COMPLIANCE APPROACHES
design, the installed system shall be field verified in accordance with the procedures specified in the applicable sections of Reference Residential Appendix RA3. B. Variable capacity heat pump (VCHP) compliance option. When performance compliance requires installation of a heat pump system that meets all the requirements of the VCHP compliance option specified in the ACM Reference Manual, the system shall be field verified in accordance with the procedures in Reference Residential Appendix RA3.4.4.3.
C. Low leakage air handler. When performance compliance requires installation of a low leakage air-handling unit, the installed air handling unit shall be field verified in accordance with the procedures specified in Reference Residential Appendix RA3.1.4.3.9. D. Thermal balancing valve. When performance compliance requires installation of thermal balancing valves with variable speed circulation pump(s), the installation shall meet the procedures specified in Reference Residential Appendix RA4.4.3. E. Heat pump—rated heating capacity.
CRC § 5.10.1. Medium relevance — show source text
For additional information on disconnect switches and distributed generation requirements, see PG&E’s Distribution Interconnection Handbook .
B. Virtual Net Energy Metering − VNEM (NEMV)
This program allows qualified participants to install a single solar system to cover the electricity load of both common and tenant metered areas connected at the same service delivery point.
This Electric Rate Schedules table helps housing owners allocate a solar system’s electricity to tenants enabling residents to receive the direct benefits of the building’s solar system without requiring the generator to be physically connected to each billing meters.
Refer to Numbered Document 076249, “Virtual Net Energy Metering Installations,” found in Appendix C, which explains the requirements for VNEM installations and illustrates the various metering and connection options for VNEM projects. Check the PG&E Electric Rate Schedules website for the latest information on this program.
C. Requirements for Generators That Are Not Permanently Connected (i.e., Temporary Connections)
Portable electric generators must be connected as described in the California Health and Safety Code, Division 104, Part 15, Chapter 5, Section 119075(b). This code says that any portable electric generator that can be connected temporarily to an applicant’s electrical system, and that is supplied typically by an electrical corporation or state or local public agency, can be connected only after separating the applicant’s electrical system from that of the electrical corporation or state or local agency.
This rule applies to any generator connected as a temporary (i.e., nonroutine, nonscheduled) or emergency source of power.
Connect any portable electric generator that is used periodically as a source of power, either on an as-needed or scheduled basis, as described in Subsection 5.10.1.D., on Page 5-45. An example would be a generator used to provide backup power for equipment maintenance.
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Section 5, Electric Metering: General
5.10.1. (continued)
D. Requirements for Generators That Are Connected Either Permanently or Periodically to an Electrical Service and Used on a Planned, Routine, or Scheduled Basis, but Do Not Operate in Parallel with the PG&E System.
Generators falling under this category must have a disconnect switch that is accessible to, and in a location approved by, the serving utility.
CRC § 11-23 Medium relevance — show source text
. . . . . . . . 11-23_ 1113 Existing Group R-1 and Group R-2 Occupancies [SFM] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-23 1114 Existing High-Rise Buildings [SFM]. . . . . . . . . . . . . . . 11-25 1115 Existing Group I Occupancies [SFM]. . . . . . . . . . . . . . 11-28 1116 Existing Group L and Group H-8 Occupancies [SFM] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-28
CHAPTER 12 ENERGY SYSTEMS . . . . . . . . . . . . . . . . . . . . .12-3
1201 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-3
1202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-3
1203 Emergency and Standby Power Systems. . . . . . . . . 12-3 1204 Portable Generators . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-6
1205 Solar Photovoltaic Power Systems . . . . . . . . . . . . . . 12-6 1206 Stationary Fuel Cell Power Systems . . . . . . . . . . . . . 12-9 1207 Electrical Energy Storage Systems (ESS) . . . . . . . .12-10
CHAPTERS 13–19 RESERVED . . . . . . . . . . . . . . . . . . . . . . .13-1
CHAPTER 20 AVIATION FACILITIES. . . . . . . . . . . . . . . . . . .20-3
2001 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-3
2002 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-3
2003 General Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-3
CRC § 5.10.1. Medium relevance — show source text
Portable electric generators must be connected as described in the California Health and Safety Code, Division 104, Part 15, Chapter 5, Section 119075(b). This code says that any portable electric generator that can be connected temporarily to an applicant’s electrical system, and that is supplied typically by an electrical corporation or state or local public agency, can be connected only after separating the applicant’s electrical system from that of the electrical corporation or state or local agency.
This rule applies to any generator connected as a temporary (i.e., nonroutine, nonscheduled) or emergency source of power.
Connect any portable electric generator that is used periodically as a source of power, either on an as-needed or scheduled basis, as described in Subsection 5.10.1.D., on Page 5-45. An example would be a generator used to provide backup power for equipment maintenance.
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Generator
Section 5, Electric Metering: General
5.10.1. (continued)
D. Requirements for Generators That Are Connected Either Permanently or Periodically to an Electrical Service and Used on a Planned, Routine, or Scheduled Basis, but Do Not Operate in Parallel with the PG&E System.
Generators falling under this category must have a disconnect switch that is accessible to, and in a location approved by, the serving utility.
These generators must be connected as described in PG&E’s Electric Rule 2 , “Description of Service,” Item E.6, and in the California Health and Safety Code , Division 104, Part 15, Chapter 5, Section 119075(c). These rules state that any electrical generator that can be permanently connected to an applicant’s electrical system must be connected only by means of a double throw switch (see Figure 5-23 on Page 5-45). This switch isolates the applicant’s electrical system from that of the electrical corporation or state or local agency.
E XCEPTION : Generators that are designed to run in parallel with the servicing utility’s system, and that are approved by that utility, are exempt from these rules.
The double throw switch may be either a manual or automatic transfer switch meeting the requirements of UL Standard 1008, “Transfer Switch Equipment.” The switch may be an integral part either of the generator assembly or of the service facilities, and must be approved by the authorities having jurisdiction.
CRC § 2702.1 Medium relevance — show source text
SECTION 2702—EMERGENCY AND STANDBY POWER SYSTEMS
[F] 2702.1 General. Emergency power systems and standby power systems shall comply with Sections 2702.1.1 through 2702.1.8.
[F] 2702.1.1 Stationary generators. Stationary emergency and standby power generators required by this code shall be listed in accordance with UL 2200.
[F] 2702.1.2 Fuel-line piping protection. Fuel lines supplying a generator set inside a high-rise building or new Group I-2 occu- pancy having occupied floors located more than 75 feet (23 m) above the lowest level of fire department vehicle access shall be separated from areas of the building other than the room the generator is located in by one of the following methods:
A fire-resistant pipe-protection system that has been tested in accordance with UL 1489. The system shall be installed as tested and in accordance with the manufacturer’s installation instructions, and shall have a rating of not less than 2 hours. Where the building is protected throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1, the required rating shall be reduced to 1 hour.
An assembly that has a fire-resistance rating of not less than 2 hours. Where the building is protected throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1, the required fire-resistance rating shall be reduced to 1 hour.
Other approved methods.
[F] 2702.1.3 Installation. Emergency power systems and standby power systems required by this code or the California Fire Code shall be installed in accordance with the California Fire Code, the California Electrical Code, NFPA 110 and NFPA 111.
[F] 2702.1.4 Load transfer. Emergency power systems shall automatically provide secondary power within 10 seconds after primary power is lost, unless specified otherwise in this code. Standby power systems shall automatically provide secondary power within 60 seconds after primary power is lost, unless specified otherwise in this code.
[F] 2702.1.5 Load duration. Emergency power systems and standby power systems shall be designed to provide the required power for a minimum duration of 2 hours without being refueled or recharged, unless specified otherwise in this code.
[F] 2702.1.6 Uninterruptable power source. An uninterrupted source of power shall be provided for equipment where required by the manufacturer’s instructions, the listing, this code or applicable referenced standards.
[F] 2702.1.7 Interchangeability. Emergency power systems shall be an acceptable alternative for installations that require standby power systems.
[F] 2702.1.8 Group I-2 occupancies. In Group I-2 occupancies located in flood hazard areas established in Section 1612.3, where new essential electrical systems are installed, and where new essential electrical system generators are installed, the systems and generators shall be located and installed in accordance with ASCE 24. Where connections for hookup of temporary generators are provided, the connections shall be located at or above the elevation required in ASCE 24.
[F] 2702.2 Where required. Emergency and standby power systems shall be provided where required by Sections 2702.2.1 through 2702.2.19.
Frequently asked questions
What CRC section covers residential battery storage and basic limits?
Energy storage for residences is primarily addressed in CRC Section R330 (Energy Storage Systems). R330 requires listed equipment (UL 9540), prescribes permitted locations and unit separation, and sets maximum per‑unit and aggregate energy limits (see §R330.1 and §R330.5) .
Do I need a permit and other agency approvals for an ESS or generator?
Yes. ESS installations regulated by the Fire Code require a construction permit (see Fire Code §105.6.6), and many systems must be installed per manufacturer instructions, listing standards and the California Electrical Code; generator installations also follow Building and Fire Code provisions for listing, piping and transfer equipment .
How do the CRC and the Fire/Building Codes interact on ESS and generators?
The CRC sets residential siting and basic requirements (R330/R331), while Chapter 12 of the California Fire Code (notably §1207 for ESS and §1203 for standby/emergency power) contains detailed thresholds, commissioning, separations and operational requirements; the Building Code and Electrical Code provide structural, mechanical and wiring standards that must also be met .
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