Title 24 · California Energy Code

What certification and efficiency rules apply to electrical power distribution equipment and transformers?

If you’re installing a distribution transformer or other listed power‑distribution equipment in California, the manufacturer must certify the unit’s compliance to the Energy Commission before installation under **§ 110.11**; specifically, **low‑voltage dry‑type distribution transformers (≤600 V)** must be certified per Title 20 unless they are one of the exceptions listed in the code — verify by checking the Energy Commission database or obtaining the manufacturer’s signed declaration.

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Last reviewed: July 6, 2026

What the code requires — 2-4 sentences

The California Energy Code requires that any electrical power distribution equipment listed in this section be installed only if the manufacturer has certified the equipment’s compliance to the Energy Commission — this is the controlling rule in § 110.11. For transformers, low‑voltage dry‑type distribution transformers (those with input voltage 600 volts or less) must be certified under the Title 20 Appliance Efficiency Regulations, unless they meet one of the enumerated exceptions in § 110.11(a). Manufacturer certification and the accepted methods to verify certification are handled by the general certification rules in § 110.0 and § 110.1.

The single most important rule: Any equipment listed in § 110.11 may be installed only after the manufacturer certifies to the Commission that it complies with the applicable requirements of that section.

Requirements in detail

Who must certify

  • Manufacturer certification required: Any electrical power distribution system equipment listed in § 110.11 may only be installed if the manufacturer has certified to the Commission that the equipment complies with that section. § 110.11 (Certification by Manufacturers).

  • How certification is verified in practice: Part 6’s general rules require that appliances and devices either be listed in the Energy Commission’s certified appliances database or be accompanied by a manufacturer’s declaration under penalty of perjury, as specified in § 110.0(b) and § 110.1(b).

Transformers covered (scope)

  • Covered transformer type: Low‑voltage dry‑type distribution transformers — defined as distribution transformers with input voltage 600 volts or less, air‑cooled, and not using oil as a coolant — are explicitly required to be certified per § 110.11(a).

Exceptions (transformer types that are NOT covered by § 110.11(a) requirement)

§ 110.11(a) lists the exceptions; notable ones include (non‑exhaustive list — see the code for full list):

  • Autotransformers
  • Drive (isolation) transformers
  • Grounding transformers
  • Machine‑tool (control) transformers
  • Non‑ventilated transformers
  • Rectifier transformers
  • Regulating transformers
  • Sealed transformers
  • Special‑impedance transformers
  • Testing transformers
  • Transformers with a tap range of 20 percent or more
  • Uninterruptible power supply (UPS) transformers
  • Welding transformers
    These exceptions are expressly listed in § 110.11(a) Exception.

How to demonstrate compliance / verification paths

  • Use the Energy Commission’s appliance certification database when the equipment is within Title 20 scope, per § 110.1(b)(1). Alternatively, use an equivalent federal directory or an approved trade association directory as allowed in § 110.1(b).

  • Where a device is not in the database but is required to be certified by Part 6, the manufacturer’s signed declaration (under penalty of perjury) that the device meets Part 6 requirements is acceptable, per § 110.0(b)(2) and related certification language in § 110.1(b)(2).

  • The code defines “CERTIFIED TO THE ENERGY COMMISSION” to mean either certification under Title 20 Section 1606 (when applicable) or a manufacturer declaration executed under penalty of perjury, and that the device was tested using the applicable Part 6 test method if required. See the definitions in Part 6.

Decision‑relevant summary table

Decision item Key value / threshold Code reference
Is manufacturer certification required? Yes — for equipment listed in the section § 110.11
Transformer type covered Low‑voltage dry‑type distribution transformer (input voltage ≤ 600 volts, air‑cooled, non‑oil) § 110.11(a); definition in Part 6
Transformer exemptions Autotransformer; drive/isolation; grounding; machine‑tool; non‑ventilated; rectifier; regulating; sealed; special‑impedance; testing; tap range ≥ 20%; UPS; welding § 110.11(a) Exception
Acceptable verification methods Energy Commission appliance database (Title 20 Section 1606), equivalent federal/trade directories, or manufacturer declaration under penalty of perjury § 110.1(b); § 110.0(b)(2)

Exceptions & special cases

  • The transformer certification requirement in § 110.11(a) does not apply to the long enumerated list of special transformers and conditions (see the exception list in § 110.11(a)). If your transformer matches any listed exception, the §110.11(a) Title 20 certification requirement does not apply.

  • If a product is already regulated under Title 20 (Appliance Efficiency Regulations, e.g., Section 1601 scope) then certification must follow Title 20 procedures (listing in the Energy Commission database under Title 20 §1606), as reinforced by § 110.1.

  • Where Part 6 requires certification but a device is outside the Title 20 appliance scope, a manufacturer’s declaration (signed under penalty of perjury) can be used to certify compliance, per § 110.0(b)(2).

Common mistakes

  • Assuming any transformer is covered — installers often miss that § 110.11(a) applies specifically to low‑voltage dry‑type distribution transformers (≤ 600 V) and that many transformer types are explicitly exempt. Always check the exception list in § 110.11(a).

  • Relying only on manufacturer literature without confirming Energy Commission certification status (either listing in the Title 20 database or an accepted manufacturer declaration). Verification routes are set out in § 110.1(b) and § 110.0(b).

  • Confusing electrical code listing/UL listing with Energy Commission certification. A product can be UL‑listed yet still require CEC/Title 20 certification or a manufacturer declaration to comply with Part 6; check § 110.11 and the Part 6 certification rules.

Worked example — concrete scenario

Scenario: You are specifying a new 150 kVA, 480 V, dry‑type distribution transformer for a commercial building.

  1. Is it a low‑voltage dry‑type distribution transformer? Yes — input voltage 480 V (≤ 600 V) and dry‑type (air cooled). This places it squarely within the equipment described by § 110.11(a).

  2. Certification requirement: The manufacturer must certify to the Commission that this transformer complies with applicable Part 6 requirements and Title 20 Appliance Efficiency Regulations, unless the transformer matches one of the exceptions (it does not in this case). See § 110.11(a).

  3. How to document compliance for plan check / field inspection:

    • First: check the Energy Commission’s appliance certification database (Title 20) for the transformer model as allowed in § 110.1(b)(1). If it is listed there, note the listing.
    • If not listed: obtain from the manufacturer a signed declaration (under penalty of perjury) certifying compliance with the applicable test methods and Part 6 requirements, as allowed by § 110.0(b)(2) and § 110.1(b)(2).

  4. Keep the certification record with construction documents and provide it to the enforcing agency or the Commission, per the general certification/verification pathways in Part 6.

Related provisions

  • § 110.0 — Systems and equipment general certification requirements and definitions.
  • § 110.1 — Mandatory requirements and verification paths for appliances and certified equipment (Title 20 database, manufacturer declaration).
  • § 110.2 — (Related) certification requirements for space‑conditioning equipment — shows the pattern for how Part 6 applies efficiency tables and testing methods.
  • § 130.5 / § 160.6 — Other electrical power distribution system rules that may affect metering, system design, and alterations (useful when transformers are part of a larger distribution work scope).

Code references

Grounded in the retrieved California Energy Code — click a citation to read the verbatim passage:

  • § 110.10 High relevance — show source text

    (d) Documentation. A copy of the construction documents or a comparable document indicating the information from Sections 110.10(b) through 110.10(c) shall be provided to the occupant.

    (e) Main electrical service panel.

    1. The main electrical service panel shall have a minimum busbar rating of 200 amps.
    2. The main electrical service panel shall have a reserved space to allow for the installation of a double pole circuit breaker for a future solar electric installation. The reserved space shall be permanently marked as “For Future Solar Electric”.

    Note: Authority: Sections 25213, 25218, 25218.5, 25402, 25402.1, and 25605, Public Resources Code. Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.8, 25605, and 25943, Public Resources Code.

    SECTION 110.11—MANDATORY REQUIREMENTS FOR ELECTRICAL POWER DISTRIBUTION SYSTEM

    Certification by Manufacturers. Any electrical power distribution system equipment listed in this section may be installed only if the manufacture has certified to the Commission that the equipment complies with all the applicable requirements of this section.

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    ALL OCCUPANCIES—MANDATORY REQUIREMENTS FOR THE MANUFACTURE, CONSTRUCTION AND INSTALLATION OF SYSTEMS, EQUIPMENT AND BUILDING COMPONENTS

    (a) Low-voltage dry-type distribution transformer shall be certified by the Manufacturer as required by the Title 20 Appliance Efficiency Regulations.

    EXCEPTION to Section 110.11(a):

    1. autotransformer;

    2. drive (isolation) transformer;

    3. grounding transformer;

    4. machine-tool (control) transformer;

    5. nonventilated transformer;

    6. rectifier transformer;

    7. regulating transformer;

    8. sealed transformer;

    9. special-impedance transformer;

    10. testing transformer;

    11. transformer with tap range of 20 percent or more;

    12. uninterruptible power supply transformer; or

    13. welding transformer.

    Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code. Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.8, and 25943, Public Resources Code.

    SECTION 110.12 — MANDATORY REQUIREMENTS FOR DEMAND MANAGEMENT

    Buildings, other than healthcare facilities, that install or are required to install demand responsive controls shall comply with the applicable demand responsive control requirements of Sections 110.12(a) through 110.12(e). (a) Demand responsive controls.

    1. All demand responsive controls shall be either: A. A certified OpenADR 2.0a or OpenADR 2.0b Virtual End Node (VEN), as specified under Clause 11, Conformance, in the applicable OpenADR 2.0 Specification; or a certified Baseline Profile OpenADR 3.0 Virtual End Node; or
  • § 100.1 High relevance — show source text

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    ALL OCCUPANCIES—GENERAL PROVISIONS

    FIGURE 100.1-A CALIFORNIA CLIMATE ZONES

    Climate Zones for Residential and Nonresidential Occupancies

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    2 ALL OCCUPANCIES—MANDATORY REQUIREMENTS FOR THE

    MANUFACTURE, CONSTRUCTION AND INSTALLATION OF SYSTEMS, EQUIPMENT AND BUILDING COMPONENTS

    SECTION 110.0—SYSTEMS AND EQUIPMENT—GENERAL

    Sections 110.1 through 110.12 specify requirements for manufacturing, construction and installation of certain systems, equipment, appliances and building components that are installed in buildings within the scope of Section 100.0(a).

    Note: The requirements of Sections 110.0 through 110.12 apply to newly constructed buildings. Sections 141.0 and 150.2 specify which requirements of Sections 110.1 through 110.12 also apply to additions and alterations to existing buildings.

    (a) General Requirements. Systems, equipment, appliances and building components shall only be installed in a building within the scope of Section 100.0(a) regulated by Part 6 only if:

    1. The manufacturer has certified that the system, equipment, appliances or building component complies with the applicable manufacturing provisions of Sections 110.1 through 110.12; and
    2. The system, equipment, appliance or building component complies with all applicable installation provisions of Sections 110.1 through 110.12.

    (b) Certification Requirements for Manufactured Systems, Equipment, Appliances and Building Components.

    1. Appliances that are within the scope of Section 1601 of the Appliance Efficiency Regulations shall only be installed if they have been certified to the Energy Commission by the manufacturer, pursuant to the provisions of Title 20 California Code of Regulations, Section 1606; or
    2. Systems, equipment, appliances and building components that are required by Part 6 or the Reference Appendices to be certified to the Energy Commission, which are not appliances that are within the scope of Section 1601 of the Appliance Efficiency Regulations, shall only be installed if they are certified by the manufacturer in a declaration, executed under penalty of perjury under the laws of the State of California, that: A. All the information provided pursuant to the certification is true, complete, accurate and in compliance with all applicable requirements of Part 6; and B. The equipment, product, or device was tested using the test procedure specified in Part 6 if applicable
    3. The certification status of any system, equipment, appliance or building component shall be confirmed only by reference to: A. A directory published or approved by the Commission; or B. A copy of the application for certification from the manufacturer and the letter of acceptance from the Commission staff; or C. Written confirmation from the publisher of a Commission-approved directory that a device has been certified; or D. A Commission-approved label on the device.

    Note: Part 6 does not require a builder, designer, owner, operator, or enforcing agency to test any certified device to determine its compliance with minimum specifications or efficiencies adopted by the Commission.

  • § 25218.5 High relevance — show source text

    (b) Certification Requirements for Manufactured Systems, Equipment, Appliances and Building Components.

    1. Appliances that are within the scope of Section 1601 of the Appliance Efficiency Regulations shall only be installed if they have been certified to the Energy Commission by the manufacturer, pursuant to the provisions of Title 20 California Code of Regulations, Section 1606; or
    2. Systems, equipment, appliances and building components that are required by Part 6 or the Reference Appendices to be certified to the Energy Commission, which are not appliances that are within the scope of Section 1601 of the Appliance Efficiency Regulations, shall only be installed if they are certified by the manufacturer in a declaration, executed under penalty of perjury under the laws of the State of California, that: A. All the information provided pursuant to the certification is true, complete, accurate and in compliance with all applicable requirements of Part 6; and B. The equipment, product, or device was tested using the test procedure specified in Part 6 if applicable
    3. The certification status of any system, equipment, appliance or building component shall be confirmed only by reference to: A. A directory published or approved by the Commission; or B. A copy of the application for certification from the manufacturer and the letter of acceptance from the Commission staff; or C. Written confirmation from the publisher of a Commission-approved directory that a device has been certified; or D. A Commission-approved label on the device.

    Note: Part 6 does not require a builder, designer, owner, operator, or enforcing agency to test any certified device to determine its compliance with minimum specifications or efficiencies adopted by the Commission.

    Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code . Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.5 , 2 5402.8, and 25943, Public Resources Code.

    SECTION 110.1—MANDATORY REQUIREMENTS FOR APPLIANCES

    (a) Any appliance regulated by the Appliance Efficiency Regulations, Title 20 California Code of Regulations, Section 1601 et seq., may be installed only if the appliance fully complies with Section 1608(a) of those regulations.

    (b) Except for those circumstances described in Section 110.1(c), conformance with efficiency levels required to comply with Part 6 mandatory, prescriptive and performance standards shall be verified utilizing data from either:

    1. The Energy Commission’s database of certified appliances maintained pursuant to Title 20 California Code of Regulations Section 1606, and which is available at: www.energy.ca.gov/appliances/database/ ; or
    2. An equivalent directory published by a federal agency; or
    3. An approved trade association directory as defined in Title 20 California Code of Regulations Section 1606(h).

    (c) Conformance with efficiency levels required to comply with Part 6 mandatory, prescriptive and performance standards shall be demonstrated either by default to the mandatory efficiency levels specified in Part 6 or by following procedures approved by the Commission pursuant to Section 10-109 of Title 24, Part 1, when:

    1. Data to verify conformance with efficiency levels required to comply with Part 6 mandatory, prescriptive and performance standards is not available pursuant to subdivision (b); or
    2. Field verification and diagnostic testing is required for compliance with Part 6 and the Energy Commission has not approved a field verification and diagnostic test protocol that is applicable to the appliance; or
  • § 13.3 High relevance — show source text

    CERTIFIED TO THE ENERGY COMMISSION means, when used in association with appliances, certified under Section 1606 of Title 20 of the California Code of Regulations; and otherwise means certified by the manufacturer in a declaration, executed under penalty of perjury under the laws of the State of California, that all the information provided pursuant to the certification is true, complete, accurate and in compliance with all applicable provisions of Part 6; and if applicable that the equipment, product or device was tested under the applicable test method specified in Part 6.

    CERTIFYING ORGANIZATION is an independent organization recognized by the Commission to certify manufactured devices for performance values in accordance with procedures adopted by the Commission.

    CIE 13.3 is the International Commission on Illumination (Commission Internationale de l’Eclairage) document titled “Method of Measuring and Specifying Colour Rendering Properties of Light Sources,” 1995 (CIE 13.3-1995).

    CIE 15 is the International Commission on Illumination (Commission Internationale de l’Eclairage) document titled “Technical Report: Colorimetry,” 2018 (CIE 15:2018).

    CIRCULATING FAN means a fan that is not a ceiling fan, but that is used to move air within a space that has no provision for connection to ducting or separation of the fan inlet from its outlet, and designed to be used for the general circulation of air.

    CLIMATE ZONES are the 16 geographic areas of California for which the commission has established typical weather data, prescriptive packages and energy budgets. Climate zones are defined by ZIP code and listed in Reference Joint Appendix JA2. FIGURE 100.1-A is an approximate map of the 16 climate zones.

    CLOSED-CIRCUIT COOLING TOWER is a cooling tower that utilizes indirect contact between a heated fluid, typically water or glycol, and the cooling atmosphere to transfer the source heat load through sensible heat, latent heat and mass transfer indirectly to the air, essentially combining a heat exchanger and cooling tower into an integrated and relatively compact device.

    CODES, CALIFORNIA HISTORICAL BUILDING CODE is the California Historical Building Code, California Code of Regulations, Title 24, Part 8 and Part 2 (Chapter 34).

    CODES, CBC is the 2025 California Building Code.

    CODES, CEC is the 2025 California Electrical Code.

    CODES, CFC is the 2025 California Fire Code.

    CODES, CMC is the 2025 California Mechanical Code.

    CODES, CPC is the 2025 California Plumbing Code.

    COEFFICIENT OF PERFORMANCE (COP), COOLING is the ratio of the rate of net heat removal to the rate of total energy input, calculated under designated operating conditions and expressed in consistent units, as determined using the applicable test method in the Appliance Efficiency Regulations or Section 110.2.

    COEFFICIENT OF PERFORMANCE (COP), HEATING is the ratio of the rate of net heat output to the rate of total energy input, calculated under designated operating conditions and expressed in consistent units, as determined using the applicable test method in the Appliance Efficiency Regulations or Section 110.2.

    COEFFICIENT OF PERFORMANCE (COP), HEAT PUMP is the ratio of the rate of useful heat output delivered by the complete heat pump unit (exclusive of supplementary heating) to the corresponding rate of energy input, in consistent units and as determined using the applicable test method in Appliance Efficiency Regulations or Section 110.2.

  • § 106.8.2 High relevance — show source text

    Install a rainwater catchment system designed to comply with the California Plumbing Code and any applicable local ordinances, and that uses rainwater flowing from at least 65 percent of the available roof

    area.

    B. Meet the Title 24, Part 11, Section A4.106.8.2 requirements for electric vehicle charging spaces.

    Exception 5 to Section 110.10(b)1B: Buildings where the roof is designed and approved to be used for vehicular traffic or parking or for a heliport. 2. Azimuth range. All sections of the solar zone located on steep-sloped roofs shall have an azimuth range between 90 degrees and 300 degrees of true north. 3. Shading. A. No obstructions, including but not limited to, vents, chimneys, architectural features and roof mounted equipment, shall be located in the solar zone.

    B. Any obstruction, located on the roof or any other part of the building that projects above a solar zone shall be located at least twice the distance, measured in the horizontal plane, of the height difference between the highest point of the obstruction and the horizontal projection of the nearest point of the solar zone, measured in the vertical plane. Exception to Section 110.10(b)3: Any roof obstruction, located on the roof or any other part of the building, that is oriented north of all points on the solar zone. 4. Structural design loads on construction documents. For areas of the roof designated as solar zone, the structural design loads for roof dead load and roof live load shall be clearly indicated on the construction documents.

    Note: Section 110.10(b)4 does not require the inclusion of any collateral loads for future solar energy systems.

    (c) Interconnection pathways.

    1. The construction documents shall indicate a location reserved for inverters and metering equipment and a pathway reserved for routing of conduit from the solar zone to the point of interconnection with the electrical service.
    2. For single-family residences and central water-heating systems, the construction documents shall indicate a pathway for routing of plumbing from the solar zone to the water-heating system.

    (d) Documentation. A copy of the construction documents or a comparable document indicating the information from Sections 110.10(b) through 110.10(c) shall be provided to the occupant.

    (e) Main electrical service panel.

    1. The main electrical service panel shall have a minimum busbar rating of 200 amps.
    2. The main electrical service panel shall have a reserved space to allow for the installation of a double pole circuit breaker for a future solar electric installation. The reserved space shall be permanently marked as “For Future Solar Electric”.

    Note: Authority: Sections 25213, 25218, 25218.5, 25402, 25402.1, and 25605, Public Resources Code. Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.8, 25605, and 25943, Public Resources Code.

    SECTION 110.11—MANDATORY REQUIREMENTS FOR ELECTRICAL POWER DISTRIBUTION SYSTEM

    Certification by Manufacturers. Any electrical power distribution system equipment listed in this section may be installed only if the manufacture has certified to the Commission that the equipment complies with all the applicable requirements of this section.

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  • § 130.5 High relevance — show source text

    ELECTRICAL POWER DISTRIBUTION SYSTEMS. The following definitions are intended to apply to Section 130.5 only:

    ELECTRICAL METERING is a device or system for measuring the electrical power and energy supplied to a customer or premise(s).

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    ALL OCCUPANCIES—GENERAL PROVISIONS

    EQUIPMENT. A general term, including devices, luminaires, apparatus, machinery, and the like used as a part of, or in connection with, an electrical installation.

    LOW VOLTAGE DRY-TYPE DISTRIBUTION TRANSFORMER is a distribution transformer that has an input voltage of 600 volts or less, that is air-cooled, and that does not use oil as a coolant.

    PLUG LOAD is the energy consumed by any appliances or electronic device that is plugged into a receptacle or receptacle outlet. Plug loads are not related to general lighting, heating, ventilation, cooling, and water heating, domestic and service water system, renewable power, information technology equipment, computer room electronic equipment, and electric vehicle charging.

    SERVICE is the conductors and equipment for delivering electric energy from the serving utility to the wiring system of the premise served.

    SERVICE EQUIPMENT is the necessary equipment, usually consisting of a circuit breaker(s) or switch(es) and fuse(s) and their accessories, connected to the load end of service conductors to a building or other structure, or an otherwise designated area, and intended to constitute the main control and cutoff of the supply.

    ELECTRONICALLY-COMMUTATED MOTOR is a brushless DC motor with a permanent magnet rotor that is surrounded by stationary motor windings, and an electronic controller that varies rotor speed and direction by sequentially supplying DC current to the windings.

    EMITTANCE, THERMAL is the ratio of the radiant heat flux emitted by a sample to that emitted by a blackbody radiator at the same temperature.

    ENCLOSED SPACE is space that is substantially surrounded by solid surfaces, including walls, ceilings or roofs, doors, fenestration areas, and floors or ground.

    ENERGY BUDGET is the maximum energy consumption that a proposed building, or portion of a building, can be designed to consume, calculated using Commission-approved compliance software as specified by Section 10-109 of the Energy Code and the Alternative Calculation Method Reference Manual. The energy budget for newly constructed buildings are expressed in terms of the Long-Term System Cost (LSC) and Source Energy. The energy budget for additions and alterations is expressed in terms of LSC.

    ENERGY COMMISSION (CEC) is the California State Energy Resources Conservation and Development Commission.

    ENERGY EFFICIENCY RATIO (EER) is the ratio of net cooling capacity (in Btu/hr) to total rate of electrical energy input (in watts), of a cooling system under designated operating conditions, as determined using the applicable test method in the Appliance Efficiency Regulations or Section 110.2.

    ENERGY EFFICIENCY RATIO 2 (EER2) is the ratio of the average rate of space cooling capacity (Btu/h) delivered to the average rate of electrical energy consumed by the air conditioner or heat pump as determined in accordance to the test method in 10CFR430 Subpart B Appendix M1. EER is expressed in Btu/Wh.

  • § 120.5 High relevance — show source text

    120.5 Required Nonresidential Mechanical System Acceptance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

    120.6 Mandatory Requirements for Covered

    Processes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

    120.7 Mandatory Requirements for Building Envelopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

    120.8 Nonresidential Building Commissioning. . . . . . . . . . 91

    120.9 Mandatory Requirements for Commercial Boilers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

    120.10 Mandatory Requirements for Fans. . . . . . . . . . . . . . . . 93

    SUBCHAPTER 4 NONRESIDENTIAL AND HOTEL/MOTEL OCCUPANCIES—MANDATORY REQUIREMENTS FOR LIGHTING SYSTEMS AND EQUIPMENT, AND ELECTRICAL

    POWER DISTRIBUTION SYSTEMS . . . . . . . . . . . . . . . . . . . . 95

    130.0 Lighting Systems and Equipment, and Electrical Power Distribution Systems—General . . . . . . . . . . . 95

    130.1 Mandatory Indoor Lighting Controls . . . . . . . . . . . . . . 96

    130.2 Outdoor Lighting Controls and Equipment . . . . . . .100

    130.3 Sign Lighting Controls. . . . . . . . . . . . . . . . . . . . . . . . . .101

    130.4 Lighting Control Acceptance and Installation Certificate Requirements. . . . . . . . . . . . . . . . . . . . . .101

    130.5 Electrical Power Distribution Systems . . . . . . . . . . .102

    SUBCHAPTER 5 NONRESIDENTIAL AND

    HOTEL/MOTEL OCCUPANCIES—PERFORMANCE AND

    PRESCRIPTIVE COMPLIANCE APPROACHES FOR

    ACHIEVING ENERGY EFFICIENCY. . . . . . . . . . . . . . . . . . . . 105

    140.0 Performance and Prescriptive Compliance Approaches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105

    140.1 Performance Approach: Energy Budgets . . . . . . . . .105

    140.2 Prescriptive Approach . . . . . . . . . . . . . . . . . . . . . . . . .105

    140.3 Prescriptive Requirements for Building Envelopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105

    140.4 Prescriptive Requirements for Space-Conditioning Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114

  • § 110.1 Medium relevance — show source text

    SECTION 110.1—MANDATORY REQUIREMENTS FOR APPLIANCES

    (a) Any appliance regulated by the Appliance Efficiency Regulations, Title 20 California Code of Regulations, Section 1601 et seq., may be installed only if the appliance fully complies with Section 1608(a) of those regulations.

    (b) Except for those circumstances described in Section 110.1(c), conformance with efficiency levels required to comply with Part 6 mandatory, prescriptive and performance standards shall be verified utilizing data from either:

    1. The Energy Commission’s database of certified appliances maintained pursuant to Title 20 California Code of Regulations Section 1606, and which is available at: www.energy.ca.gov/appliances/database/ ; or
    2. An equivalent directory published by a federal agency; or
    3. An approved trade association directory as defined in Title 20 California Code of Regulations Section 1606(h).

    (c) Conformance with efficiency levels required to comply with Part 6 mandatory, prescriptive and performance standards shall be demonstrated either by default to the mandatory efficiency levels specified in Part 6 or by following procedures approved by the Commission pursuant to Section 10-109 of Title 24, Part 1, when:

    1. Data to verify conformance with efficiency levels required to comply with Part 6 mandatory, prescriptive and performance standards is not available pursuant to subdivision (b); or
    2. Field verification and diagnostic testing is required for compliance with Part 6 and the Energy Commission has not approved a field verification and diagnostic test protocol that is applicable to the appliance; or
    3. The appliance meets the requirements of Section 110.1(a) but has been site-modified in a way that affects its performance; or

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    ALL OCCUPANCIES—MANDATORY REQUIREMENTS FOR THE MANUFACTURE, CONSTRUCTION AND INSTALLATION OF SYSTEMS, EQUIPMENT AND BUILDING COMPONENTS

    1. The U.S. Department of Energy has approved a waiver from federal test procedures, pursuant to 10 CFR Section 430.27 or Section 431.401 and that waiver fails to specify how the efficiency of the system shall be determined.

    Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code . Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.5 , 2 5402.8, and 25943, Public Resources Code.

    SECTION 110.2—MANDATORY REQUIREMENTS FOR SPACE-CONDITIONING EQUIPMENT

    Certification by manufacturers. Any space-conditioning equipment listed in this section may be installed only if the manufacturer has certified to the Commission that the equipment complies with all the applicable requirements of this section.

    (a) Efficiency. Equipment shall meet the applicable efficiency requirements in Tables 110.2-A through 110.2-L, subject to the following:

    1. If more than one efficiency standard is listed for any equipment in Tables 110.2-A through 110.2-L, the equipment shall meet all the applicable standards that are listed; and
    2. If more than one test method is listed in Tables 110.2-A through 110.2-L, the equipment shall comply with the applicable efficiency standard when tested with each listed test method; and
  • § 160.6 Medium relevance — show source text

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    MULTIFAMILY BUILDINGS—MANDATORY REQUIREMENTS

    TABLE 160.6-A—MINIMUM REQUIREMENTS FOR METERING OR SUBMETERING OF ELECTRICAL LOAD Col2 Col3 Col4 Col5
    METERING
    FUNCTIONALITY    		 **ELECTRICAL SERVICES1 **
    RATED 50 KVA OR LESS    		 **ELECTRICAL SERVICES1 **
    RATED MORE THAN 50
    KVA AND LESS THAN OR
    EQUAL TO 250 KVA    		 **ELECTRICAL SERVICES1 **
    RATED MORE THAN 250
    KVA AND LESS THAN OR
    EQUAL TO 1000 KVA    		 **ELECTRICAL SERVICES1 **
    RATED MORE THAN
    1000 KVA
    Instantaneous (at the time) kW
    demand    		 Required Required Required Required
    Historical peak demand (kW) Not required Not required Required Required
    Tracking kWh for a user-
    definable period    		 Required Required Required Required
    kWh per rate period Not required Not required Not required Required
    1. “Electrical services” applies to the building service-entrance rating or to the submetering service. For a building with submetering, this applies to the submetering service size
    to the common use areas.    		 1. “Electrical services” applies to the building service-entrance rating or to the submetering service. For a building with submetering, this applies to the submetering service size
    to the common use areas.    		 1. “Electrical services” applies to the building service-entrance rating or to the submetering service. For a building with submetering, this applies to the submetering service size
    to the common use areas.    		 1. “Electrical services” applies to the building service-entrance rating or to the submetering service. For a building with submetering, this applies to the submetering service size
    to the common use areas.    		 1. “Electrical services” applies to the building service-entrance rating or to the submetering service. For a building with submetering, this applies to the submetering service size
    to the common use areas.

    (b) Separation of electrical circuits for electrical energy monitoring . Electrical power distribution systems shall be designed so that measurement devices can monitor the electrical energy usage of load types according to Table 160.6-B.

    Exception 1 to Section 160.6(b): For each separate load type, up to 10 percent of the connected load may be of any type.

    Exception 2 to Section 160.6(b): Submetered electrical power distribution systems that provide power to dwelling units.

    |TABLE 160.

  • § 6.4. Medium relevance — show source text
    1. Outdoor lighting controls shall be tested in accordance with Reference Nonresidential Appendix NA7.8; and
    2. Lighting systems receiving the Institutional Tuning Power Adjustment Factor shall be tested in accordance with Reference Nonresidential Appendix NA7.6.4.
    3. Demand responsive controls required to control controlled receptacles shall be tested in accordance with Reference Nonresidential Appendix NA7.6.5.

    (b) Lighting control installation certificate requirements. To be recognized for compliance with Part 6 an installation certificate shall be submitted in accordance with Section 10-103(a) for any lighting control system, energy management control system, interlocked lighting system, lighting power adjustment factor, or additional wattage available for a videoconference studio, in accordance with the following requirements, as applicable:

    1. Certification that when a lighting control system is installed to comply with lighting control requirements in Part 6 it complies with the applicable requirements of Section 110.9; and complies with Reference Nonresidential Appendix NA7.7.1.

    2. Certification that when an energy management control system is installed to function as a lighting control required by Part 6 it functionally meets all applicable requirements for each application for which it is installed, in accordance with Sections 110.9, 130.0 through 130.5, 140.6 through 150.0, and 150.2; and complies with Reference Nonresidential Appendix NA7.7.2.

    3. Reserved.

    4. Reserved.

    5. Certification that interlocked lighting systems used to serve an approved area comply with Section 140.6(a)1; and comply with Reference Nonresidential Appendix NA7.7.4.

    6. Certification that lighting controls installed to earn a lighting power adjustment factor (PAF) comply with Section 140.6(a)2; and comply with Reference Nonresidential Appendix NA7.7.5.

    2025 CALIFORNIA ENERGY CODE 101

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    NONRESIDENTIAL AND HOTEL/MOTEL OCCUPANCIES—MANDATORY REQUIREMENTS FOR LIGHTING SYSTEMS AND EQUIPMENT, AND ELECTRICAL POWER DISTRIBUTION SYSTEMS

    1. Certification that additional lighting wattage installed for a videoconference studio complies with Section 140.6(c)2Gvii; and complies with Reference Nonresidential Appendix NA7.7.6.

    (c) When certification is required by Title 24, Part 1, Section 10-103.1, the acceptance testing specified by Section 130.4 shall be performed by a certified lighting controls acceptance test technician (CLCATT). If the CLCATT is operating as an employee, the CLCATT shall be employed by a certified lighting controls acceptance test employer. The CLCATT shall disclose on the Certificate of Acceptance a valid CLCATT certification identification number issued by an approved acceptance test technician certification provider. The CLCATT shall complete all certificate of acceptance documentation in accordance with the applicable requirements in Section 10-103(a)4.

    Note: Authority cited: Sections 25402, 25402.1 and 25213, Public Resources Code . Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.5, 25402.8, and 25943, Public Resources Code .

    SECTION 130.5—ELECTRICAL POWER DISTRIBUTION SYSTEMS

  • § 160.3 Medium relevance — show source text

    3(c)1, Table 160.3-D, Table 160.4-A Conductor 150.0(N), 160.4(A)1 Conduit 110.10(c), 110.8(g)2 Conference Room 130.1(C)5, 130.5(D), 140.6(a)1, 160.5(b)4C, 160.6(d), 170.2(e)2A Connected Boiler 120.6(i) Constant Loads 140.4(F), 170.2(C)4D Constant Volume 120.4(G), 120.5(A)2, 140.9(c)1, 141.0(b)2D, 160.2(c)7C, 160.3(c)2H, 160.3(d)1, 180.2(b)2B Construction 110.0, 120.1(G)7, 120.8(C), 120.8(i), 140.3(a)1A, 140.3(a)9, 141.0(b)2B, 150.0(m)1B, 11B, 150.1(c)11, 150.2(b)1I, 160.2(c)8G, 160.3(b)5A, 170.2(a)1A, 170.2(e)2B, 180.2(b)1A Construction Documents 110.10(B)4, 110.10(c), 110.10(d), 120.8(a)4, 120.8(d), 120.8(e), 140.6(a)2J, 140.6(a)3A, B, C Contaminant Level 120.6(c) Contiguous Areas 140.6(C)2, 140.6(C)3, 170.2(e)4 Continuous Insulation Table 141.0-C, 150.1(c)1, 150.2(a)1A, 150.2(a)1B, 150.2(b)1I, 180.1(a)1A, Table 180.2-A, 180.2(b)1A Local ventilation exhaust airflow rates

  • § 503.4.3 Medium relevance — show source text

    E 503.4.3 Verification of Equipment Efficiencies. Equipment efficiency information supplied by manufacturers shall be verified in accordance with one of the following:

    (1) Equipment covered under EPACT shall be in accordance with U.S. Department of Energy certification requirements.

    (2) Where a certification program exists for a covered product, and it includes provisions for verification and challenge of equipment efficiency ratings, then the product shall be listed in the certification program.

    (3) Where a certification program exists for a covered product, and it includes provisions for verification and challenge of equipment efficiency ratings, but the product is not listed in the existing certification program, the ratings shall be verified by an independent laboratory test report.

    (4) Where no certification program exists for a covered product, the equipment efficiency ratings shall be supported by data furnished by the manufacturer.

    (5) Where components such as indoor or outdoor coils from different manufacturers are used, the system designer shall specify component efficiencies whose combined efficiency is in accordance with the minimum equipment efficiency requirements in Section E 503.4 through Section E 503.4.4.1. [ASHRAE 90.1:6.4.1.5]

    E 503.4.4 Mechanical Equipment Labeling. Mechanical equipment that is not covered by the U.S. National Appliance Energy Conservation Act (NAECA) of 1987 shall carry a permanent label installed by the manufacturer stating that the equipment is in accordance with the requirements of ASHRAE 90.1. [ASHRAE 90.1:6.4.1.6.1]

    E 503.4.4.1 Packaged Terminal Air Condi- tioners. Nonstandard-size packaged terminal air conditioners and heat pumps with existing sleeves having an external wall opening of less than 16 inches (406 mm) high or less than 42 inches (1067 mm) wide and having a cross-sectional area less than 670 square inches (0.432 m [2] ) shall be factory labeled as follows:

    Manufactured for nonstandard-size applications only: Not to be installed in new construction projects. [ASHRAE 90.1:6.4.1.6.2]

    E 503.4.5 Load Calculations. Heating and cooling system design loads for the purpose of sizing systems and equipment shall be determined in accordance with ASHRAE/ACCA 183. [ASHRAE 90.1:6.4.2.1]

    E 503.4.5.1 Pump Head. Pump differential pressure (head) for the purpose of sizing pumps shall be determined in accordance with generally accepted engineering standards and handbooks acceptable to the Authority Having Jurisdiction. The pressure drop through each device and pipe segment in the critical circuit at design conditions shall be calculated.

    [ASHRAE 90.1:6.4.2.2]

    E 503.4.6 Zone Thermostatic Controls. The supply of heating and cooling energy to each zone shall be individually controlled by thermostatic controls responding to temperature within the zone. For the purposes of Section E 503.4.6, a dwelling unit shall be permitted to be considered a single zone.

    Exceptions: Independent perimeter systems that are designed to offset only building envelope loads shall be permitted to serve one or more zones also served by an interior system, provided that:

Frequently asked questions

Do all transformers need to be listed in the Energy Commission database?

Not always. Low‑voltage dry‑type distribution transformers that fall under Title 20 should be certified and are commonly listed; if a specific model is not in the database, the manufacturer’s declaration under Part 6 is an accepted alternative. § 110.11(a) and § 110.1(b) explain the paths.

What if a transformer is oil‑filled or ventilated?

The requirement in § 110.11(a) applies to low‑voltage dry‑type transformers (air‑cooled, non‑oil). Oil‑filled transformers are outside that specific wording and may be treated differently; confirm applicability and any other Part 6 or Title 20 coverage.

If a transformer is exempt under § 110.11(a) (for example a UPS transformer), do I need any documentation?

If the transformer matches an exception listed in § 110.11(a), the Title 20 certification requirement of § 110.11(a) does not apply, but other codes or standards (Electrical Code, project specs, utility requirements) still apply — always retain documentation showing why the exception applies.

Who confirms certification for plan check?

Enforcing agencies typically confirm certification by checking the Energy Commission’s database, a Commission‑approved directory, a manufacturer application and acceptance letter, or a Commission‑approved label, as described in § 110.0(b) and § 110.1(b)(3).

Where is “CERTIFIED TO THE ENERGY COMMISSION” defined?

The Part 6 definitions explain that “CERTIFIED TO THE ENERGY COMMISSION” means certification under Title 20 Section 1606 for appliances, or a manufacturer’s declaration under penalty of perjury for other Part 6 devices, including that testing followed the applicable Part 6 test method when required. See the Part 6 definitions.

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