Photovoltaic requirements, BESS (battery energy storage) sizing and SARA procedures

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

• § 1.27 High relevance — show source text

  63|1.27|1.63|1.27|1.63|1.63|1.63|1.63|1.63|1.63|1.63|1.63|1.63|2.46|1.27| |Warehouse|0.39|0.44|0.39|0.44|0.39|0.44|0.44|0.44|0.44|0.44|0.44|0.44|0.44|0.44|0.58|0.39| |Religious Worship|4.25|4.65|3.49|4.52|3.72|4.29|4.64|5.89|5.30|5.67|5.89|4.99|5.78|4.63|7.57|3.90| |Sports & Recreation|2.47|1.97|1.54|2.03|1.60|1.84|1.98|2.63|2.47|2.60|2.75|2.20|2.72|2.15|4.03|1.81| |Multifamily > 3 stories|1.82|2.21|1.82|2.21|1.82|2.21|2.21|2.21|2.21|2.21|2.21|2.21|2.21|2.21|2.77|1.82|

  (h) Battery energy storage system (BESS) requirements—more than three habitable stories. All buildings that are required by Section 170.2(g) to have a PV system shall also have a BESS meeting the minimum qualification requirements of Reference Joint Appendix JA12. The rated energy capacity shall be not less than the Minimum Rated Useable Energy Capacity determined by Equation 170.2-E, or by Equation 170.2-F if SARA was used to determine the PV capacity in Section 170.2-D, and the rated power capacity shall be not less than the Minimum Power Capacity determined by Equation 170.2-G. In mixed occupancy buildings, the total battery system capacity for the building shall be determined by applying the Minimum Rated Usable Energy Capacity to each of the listed building types and summing the capacities determined for each.

  EQUATION 170.2-E—BATTERY ENERGY STORAGE SYSTEM MINIMUM RATED USABLE ENERGY CAPACITY kWh batt = k((CFA × B)/(1000 × C [0.5] ))

  — EQUATION 170.2-F BATTERY ENERGY STORAGE SYSTEM MINIMUM RATED USABLE ENERGY CAPACITY, SARA-ADJUSTED kWh batt = k((CFA × B)/(1000 × C [0.5] )) × (kWP Vdc,SARA /kWP Vdc )

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  where:

  kWh batt = Minimum Rated Usable Energy Capacity of the BESS in kWh.

  kW PVdc = Minimum Rated PV System Capacity in kW from Equation 170.2D. kW PVdc, SARA = Minimum Rated PV System Capacity in kW from the SARA calculation. CFA = Conditioned floor area that is subject to the PV system requirements of Section 170.2(g) in square feet.

• § 170.2 High relevance — show source text

  The rated energy capacity shall be not less than the Minimum Rated Useable Energy Capacity determined by Equation 170.2-E, or by Equation 170.2-F if SARA was used to determine the PV capacity in Section 170.2-D, and the rated power capacity shall be not less than the Minimum Power Capacity determined by Equation 170.2-G. In mixed occupancy buildings, the total battery system capacity for the building shall be determined by applying the Minimum Rated Usable Energy Capacity to each of the listed building types and summing the capacities determined for each.

  EQUATION 170.2-E—BATTERY ENERGY STORAGE SYSTEM MINIMUM RATED USABLE ENERGY CAPACITY kWh batt = k((CFA × B)/(1000 × C [0.5] ))

  — EQUATION 170.2-F BATTERY ENERGY STORAGE SYSTEM MINIMUM RATED USABLE ENERGY CAPACITY, SARA-ADJUSTED kWh batt = k((CFA × B)/(1000 × C [0.5] )) × (kWP Vdc,SARA /kWP Vdc )

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  where:

  kWh batt = Minimum Rated Usable Energy Capacity of the BESS in kWh.

  kW PVdc = Minimum Rated PV System Capacity in kW from Equation 170.2D. kW PVdc, SARA = Minimum Rated PV System Capacity in kW from the SARA calculation. CFA = Conditioned floor area that is subject to the PV system requirements of Section 170.2(g) in square feet.

  B = BESS Capacity Factor in Wh/square foot as specified in Table 170.2-V for the building type.

  C = Rated single charge-discharge cycle AC to AC (round-trip) efficiency of the BESS.

  EQUATION 170.2-G—BATTERY ENERGY STORAGE SYSTEM MINIMUM RATED POWER CAPACITY

  kW batt = kW batt /4

  where:

  kW batt = Minimum Rated Power Capacity of the BESS in kW dc .

  kWh batt = Minimum Rated Usable Energy Capacity of the BESS in kWh.

  Exception 1 to Section 170.2(h): No BESS is required if the installed PV system capacity is less than 15 percent of the capacity determined by Equation 170.2-D.

  Exception 2 to Section 170.2(h): No BESS is required in buildings with BESS requirements with less than 10 kWh minimum rated usable energy capacity.

  |TABLE 170.

• § 140.10 High relevance — show source text

  Exception 1 to Section 140.10(a): No PV system is required where the total of all available SARA is less than 3 percent of the conditioned floor area.

  Exception 2 to Section 140.10(a): No PV system is required where the required PV system capacity is less than 4 kW dc .

  Exception 3 to Section 140.10(a): No PV system is required if the SARA contains less than 80 contiguous square feet.

  Exception 4 to Section 140.10(a): Buildings with enforcement-authority-approved roof designs, where the enforcement authority determines it is not possible for the PV system, including panels, modules, components, supports and attachments to the roof structure, to meet ASCE 7-16, Chapter 7, Snow Loads.

  Exception 5 to Section 140.10(a): For nonresidential and hotel/motel multitenant buildings, the PV capacity determined by Equation 140.10-A shall be calculated without including tenant spaces meeting all of the following: i. The tenant space is less than or equal to 2,000 square feet of conditioned space; ii. The tenant space is served by an HVAC system that does not serve other tenant spaces in the building; and iii. The tenant space has an individual utility meter to track electricity consumption that does not include the electricity consumption of other tenant spaces in the building.

  This exception does not apply where the Commission has approved a community solar program for showing compliance as specified in Title 24, Part 1, Section 10-115, or where a load-serving entity provides a program where PV generation is compensated through virtual energy bill credits for occupants of nonresidential and hotel/motel tenant spaces to receive energy bill benefits from netting of energy generation and consumption.

  (b) Battery energy storage system (BESS) requirements. All buildings that are required by Section 140.10(a) to have a PV system shall also have a BESS meeting the minimum qualification requirements of Reference Joint Appendix JA12. The rated energy capacity shall be not less than the Minimum Rated Useable Energy Capacity determined using Equation 140.10-B or 140.10-C if SARA was used to determine the PV capacity in Section 140.10(a). The rated power capacity shall be not less than the Minimum Power Capacity determined using Equation 140.10-D. In mixed occupancy buildings, the total battery system capacity for the building shall be determined by applying the Minimum Rated Usable Energy Capacity to each of the listed building types and summing the capacities determined for each.

  EQUATION 140.10-B—BATTERY ENERGY STORAGE SYSTEM MINIMUM RATED USABLE ENERGY CAPACITY kWh batt = [(CFA × B)/(1,000 × C [0.5] )]

  EQUATION 140.10-C—BATTERY ENERGY STORAGE SYSTEM MINIMUM RATED USABLE ENERGY CAPACITY, SARA-ADJUSTED kWh batt = [(CFA × B)/(1,000 × C [0.5] )] x (kW PVdc,SARA /kW PVdc )

  where:

  kWh batt = Minimum Rated Usable Energy Capacity of the BESS in kWh.

  CFA = Conditioned floor area that is subject to the PV system requirements of Section 140.10(a) in square feet.

• § 140.9 High relevance — show source text

  2. In a jurisdiction where gas heating is allowed.

  Exception 4 to Section 140.9(c)6: Buildings with an exhaust air heat recovery system and heat recovery chillers designed to provide at least 40 percent of the peak heating load from exhaust heat recovery.

  Exception 5 to Section 140.9(c)6: Exhaust systems requiring wash down systems such as exhaust systems dedicated to perchloric acid fume hoods.

  Exception to Section 140.9(c): Healthcare facilities.

  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 140.10—PRESCRIPTIVE REQUIREMENTS FOR PHOTOVOLTAIC AND BATTERY ENERGY STORAGE SYSTEMS

  (a) Photovoltaic requirements. All newly constructed building types specified in Table 140.10-A, or mixed occupancy buildings where at least 80 percent of the floor area of the building serves one or more of these building types, shall have a newly installed photovoltaic (PV) system meeting the minimum qualification requirements of Reference Joint Appendix JA11. The PV capacity in kW dc shall not be less than the smaller of the minimum rated PV system capacity determined by Equation 140.10-A, or the total of all available solar access roof areas (SARA) multiplied by 18 for steep-sloped roofs or multiplied by 14 for low-sloped roofs. In mixed occupancy buildings, the minimum rated PV system capacity for the building shall be determined by applying Equation 140.10-A to the conditioned floor area of each of the listed building types and summing the capacities determined for each.

  1. SARA includes the area of the building’s roof space capable of structurally supporting a PV system, and the area of all roof space on covered parking areas, carports and all other newly constructed structures on the site that are compatible with supporting a PV system per Title 24, Part 2, Section 1511.10.

  2. SARA does NOT include:

  A. Any area that has less than 70 percent annual solar access. Annual solar access is determined by dividing the total annual solar insolation (accounting for shading obstructions) by the total annual solar insolation if the same areas were unshaded by those obstructions. For all roofs, all obstructions, including those that are external to the building, and obstructions that are part of the building design and elevation features may be considered for the annual solar access calculations.

  B. Occupied roofs as specified by CBC Section 503.1.4. C. Roof area that is otherwise not available due to compliance with: i. Other state building code requirements; or ii. Local building code requirements if the local building code requirements are confirmed by the Executive Director.

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  EQUATION 140.10-A—PHOTOVOLTAIC DIRECT CURRENT CAPACITY

  kW PVdc = (CFA × A)/1000

  where:

  kW PVdc = Minimum rated PV system capacity in kW.

• § 140.10 High relevance — show source text

  (b) Battery energy storage system (BESS) requirements. All buildings that are required by Section 140.10(a) to have a PV system shall also have a BESS meeting the minimum qualification requirements of Reference Joint Appendix JA12. The rated energy capacity shall be not less than the Minimum Rated Useable Energy Capacity determined using Equation 140.10-B or 140.10-C if SARA was used to determine the PV capacity in Section 140.10(a). The rated power capacity shall be not less than the Minimum Power Capacity determined using Equation 140.10-D. In mixed occupancy buildings, the total battery system capacity for the building shall be determined by applying the Minimum Rated Usable Energy Capacity to each of the listed building types and summing the capacities determined for each.

  EQUATION 140.10-B—BATTERY ENERGY STORAGE SYSTEM MINIMUM RATED USABLE ENERGY CAPACITY kWh batt = [(CFA × B)/(1,000 × C [0.5] )]

  EQUATION 140.10-C—BATTERY ENERGY STORAGE SYSTEM MINIMUM RATED USABLE ENERGY CAPACITY, SARA-ADJUSTED kWh batt = [(CFA × B)/(1,000 × C [0.5] )] x (kW PVdc,SARA /kW PVdc )

  where:

  kWh batt = Minimum Rated Usable Energy Capacity of the BESS in kWh.

  CFA = Conditioned floor area that is subject to the PV system requirements of Section 140.10(a) in square feet.

  kW PVdc = Minimum Rated PV System Capacity in kW from Equation 140.10-A. kW PVdc, SARA = Minimum Rated PV System Capacity in kW from the SARA calculation. B = BESS Capacity Factor in Wh/square foot as specified in Table 140.10-B for the building type. C = Rated single charge-discharge cycle AC to AC (round-trip) efficiency of the BESS.

  EQUATION 140.10-D—BESS MINIMUM RATED POWER CAPACITY

  kW batt = kW batt /4

  where:

  kW batt = Minimum Rated Power Capacity of the BESS in kWdc. kW PVdc = Minimum Rated Useable Energy Capacity of the BESS in kWh. Exception 1 to Section 140.10(b): No BESS is required if the installed PV system capacity is less than 15 percent of the capacity determined by Equation 140.10-A.

  Exception 2 to Section 140.10(b): No BESS is required if the rated usable energy capacity determined by Equation 140.10-B or Equation 140.10-C is less than 10 kWh.

  Exception 3 to Section 140.10(b): For multitenant buildings, the energy capacity of the BESS shall be based on the tenant spaces with more than 5,000 square feet of conditioned floor area. For single-tenant buildings with less than 5,000 square feet of conditioned floor area, no BESS is required.

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  |TABLE 140.

• § 170.2 High relevance — show source text

  b. Roof areas that are not allowed to have PVs by the mandatory conditions of approval shall not be considered in determining the SARA.

  Exception 5 to Section 170.2(f): PV system sizes determined using Equation 170.2-C may be reduced by 25 percent if installed in conjunction with a BESS. The BESS shall meet the qualification requirements specified in Joint Appendix JA12 and have a minimum cycling capacity of 7.5 kWh as defined in Joint Appendix JA12.

  TABLE 170.2-T—CFA AND DWELLING UNIT ADJUSTMENT FACTORS	Col2	Col3
  CLIMATE ZONE	A—CFA	B—DWELLING UNITS
  1	0.793	1.27
  2	0.621	1.22
  3	0.628	1.12
  4	0.586	1.21
  5	0.585	1.06
  6	0.594	1.23
  7	0.572	1.15
  8	0.586	1.37
  9	0.613	1.36
  10	0.627	1.41
  11	0.836	1.44
  12	0.613	1.40
  13	0.894	1.51
  14	0.741	1.26
  15	1.56	1.47
  16	0.59	1.22

  (g) Photovoltaic requirements—more than three habitable stories. All newly constructed building types specified in Table 170.2-U, or mixed occupancy buildings where at least 80 percent of the floor area of the building serves one or more of these building types, shall have a newly installed photovoltaic (PV) system meeting the minimum qualification requirements of Reference Joint Appendix JA11. The PV capacity in kW dc shall not be less than the smaller of the minimum rated PV system capacity determined by Equation 170.2-D, or the total of all available solar access roof areas (SARA) multiplied by 18 for steep-sloped roofs or multiplied by 14 for low-sloped roofs. In mixed occupancy buildings, the minimum rated PV system capacity for the building shall be determined by applying Equation 170.2-D to the conditioned floor area of each of the listed building types and summing the capacities determined for each.

  1. SARA include the area of the building’s roof space capable of structurally supporting a PV system, and the area of all roof space on covered parking areas, carports and all other newly constructed structures on the site that are compatible with supporting a PV system per Title 24, Part 2, Section 1511.10.

  2. SARA does not include:

  A. Any area that has less than 70 percent annual solar access. Annual solar access is determined by dividing the total annual solar insolation (accounting for shading obstructions) by the total annual solar insolation if the same areas were unshaded by those obstructions. For all roofs, all obstructions including those that are external to the building,

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  and obstructions that are part of the building design and elevation features, may be considered for the annual solar access calculations.

• § 170.2 High relevance — show source text

  All multifamily buildings up to three habitable stories shall have a newly installed photovoltaic (PV) system or newly installed PV modules meeting the minimum qualification requirements specified in Joint Appendix JA11. The annual electrical output of the PV system shall be no less than the smaller of a PV system size determined using Equation 170.2-C, or the total solar access roof area (SARA) multiplied by 18 for steep-sloped roofs or SARA multiplied by 14 for low-sloped roofs. A. SARA includes the area of the building’s roof space capable of structurally supporting a PV system, and the area of all roof space on covered parking areas, carports, and all other newly constructed structures on the site that are compatible with supporting a PV system per Title 24, Part 2, Section 1511.10.

  B. SARA does NOT include:

  i. Any roof area that has less than 70 percent annual solar access. Annual solar access is determined by dividing the total annual solar insolation, accounting for shading obstructions, by the total annual solar insolation if the same areas were unshaded by obstructions. For steep-sloped roofs, only shading from existing permanent natural or manmade obstructions that are external to the dwelling, including but not limited to trees, hills and adjacent structures, shall be considered for annual solar access calculations. For low slope roofs, all obstructions including those that are external to the dwelling unit, and obstructions that are part of the building design and elevation features, shall be considered for the annual solar access calculations.

  ii. Occupied roof areas as specified by CBC Section 503.1.4. iii. Roof area that is otherwise not available due to compliance with: a. Other state building code requirements, or b. Local building code requirements if local building code requirements are confirmed by the Executive Director.

  EQUATION 170.2-C—ANNUAL PHOTOVOLTAIC ELECTRICAL OUTPUT

  kW PV = (CFA × A)/1000 + N DU × B)

  where:

  kW PV = kW dc size of the PV system.

  CFA = Conditioned floor area.

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  N DU = Number of dwelling units.

  A = CFA adjustment factor from Table 170.2-T.

  B = Dwelling unit adjustment factor from Table 170.2-T.

  Exception 1 to Section 170.2(f): For steep slope roofs, SARA shall not consider roof areas with a northerly azimuth that lies between 300 degrees and 90 degrees from true north. No PV system is required if the SARA is less than 80 contiguous square feet.

  Exception 2 to Section 170.2(f): No PV system is required when the minimum PV system size specified by Section 170.2(f) is less than 4 kW dc .

  Exception 3 to Section 170.2(f): Buildings with enforcement-authority-approved roof designs, where the enforcement authority determines it is not possible for the PV system, including panels, modules and components and supports and attachments to the roof structure, to meet the requirements of American Society of Civil Engineers (ASCE) Standard 7-16, Chapter 7, Snow Loads.

• § 140.0 Medium relevance — show source text

  Note to Section 140.0(c): The Commission periodically updates, publishes and makes available to interested persons and local enforcement agencies precise descriptions of the climate zones, which is available by zip code boundaries depicted in the Reference Joint Appendices along with a list of the communities in each zone.

  Note to Section 140.0: The requirements of Sections 140.1 through 140.10 apply to newly constructed buildings. Section 141.0 specifies which requirements of Sections 140.1 through 140.10 also apply to additions or alterations to existing buildings.

  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, 25402.8, and 25943, Public Resources Code.

  SECTION 140.1—PERFORMANCE APPROACH: ENERGY BUDGETS

  A building complies with the performance standards if the energy consumption calculated for the proposed design building is no greater than the energy budget calculated for the standard design building using Commission-certified compliance software as specified by Sections 10-109(c) and 10-116.

  (a) Energy budget. The energy budget is expressed in terms of long-term system cost (LSC) and source energy.

  1. Long-term system cost (LSC). The LSC energy budget is determined by applying the mandatory and prescriptive requirements of the standard design to the proposed design building and has two components, the Efficiency LSC and the Total LSC.

  A. The Efficiency LSC energy is the sum of the LSC energy for space-conditioning, water heating, mechanical ventilation, and lighting. 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 to the proposed design building.

  Exception to Section 140.1(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.

  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, 25402.8, and 25943, Public Resources Code.

  SECTION 140.2—PRESCRIPTIVE APPROACH

  To comply using the prescriptive approach a building shall be designed with and shall have constructed and installed systems and components meeting the applicable requirements of Sections 140.3 through 140.10.

• § 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.

  1. 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.
  2. 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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  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.

• § 170.2 Medium relevance — show source text

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  where:

  kWh batt = Minimum Rated Usable Energy Capacity of the BESS in kWh.

  kW PVdc = Minimum Rated PV System Capacity in kW from Equation 170.2D. kW PVdc, SARA = Minimum Rated PV System Capacity in kW from the SARA calculation. CFA = Conditioned floor area that is subject to the PV system requirements of Section 170.2(g) in square feet.

  B = BESS Capacity Factor in Wh/square foot as specified in Table 170.2-V for the building type.

  C = Rated single charge-discharge cycle AC to AC (round-trip) efficiency of the BESS.

  EQUATION 170.2-G—BATTERY ENERGY STORAGE SYSTEM MINIMUM RATED POWER CAPACITY

  kW batt = kW batt /4

  where:

  kW batt = Minimum Rated Power Capacity of the BESS in kW dc .

  kWh batt = Minimum Rated Usable Energy Capacity of the BESS in kWh.

  Exception 1 to Section 170.2(h): No BESS is required if the installed PV system capacity is less than 15 percent of the capacity determined by Equation 170.2-D.

  Exception 2 to Section 170.2(h): No BESS is required in buildings with BESS requirements with less than 10 kWh minimum rated usable energy capacity.

  TABLE 170.2-V—BESS CAPACITY FACTORS (Wh/ft2 of conditioned floor area)	Col2	Col3	Col4	Col5	Col6	Col7	Col8	Col9	Col10	Col11	Col12	Col13	Col14	Col15	Col16	Col17
  BUILDING TYPE	CZ 1	CZ 2	CZ 3	CZ 4	CZ 5	CZ 6	CZ 7	CZ 8	CZ 9	CZ 10	CZ 11	CZ 12	CZ 13	CZ 14	CZ 15	CZ 16
  Event & Exhibit	1.82	1.95	1.74	2.12	1.91	2.13	2.24	2.30	2.36	2.47	2.62	2.16	2.64	2.68	3.22	1.89
  Library	0.37	7.17	5.97	6.75	5.64	6.08	6.19	7.13	7.18	7.56	7.17	6.93	6.88	6.81	7.93	6.40
  Hotel/Motel	0.86	0.84	0.77	0.92	0.81	0.89	0.90	1.01	1.00	1.11	1.14	0.96	1.18	1.18	1.49	0.85
  Office, Financial Institution,

• § 10-109 Medium relevance — show source text

  (b) Performance approach. A building complies with the performance approach if the energy consumption calculated for the proposed design building is no greater than the energy budget calculated for the standard design building using Commission-certified compliance software as specified by Sections 10-109(c) and 10-116.

  1. Energy budget. The energy budget is expressed in terms of source energy and long-term system cost (LSC). A. Long-term system cost (LSC). The LSC energy budget is determined by applying the mandatory and prescriptive requirements of the standard design to the proposed design building and has two components, the Efficiency LSC and the Total LSC.

  i. The Efficiency LSC energy is the sum of the LSC energy for space-conditioning, water heating, mechanical ventilation, and the self-utilization credit.

  ii. The Total LSC energy is the sum of the Efficiency LSC energy and LSC energy from the photovoltaic system, battery energy storage systems (BESS), lighting, demand flexibility, and other plug loads. B. Source energy. The source energy budget is determined by applying the mandatory and prescriptive requirements of the standard design to the proposed design building. The source energy is the total annual source energy. Exception to Section 150.1(b)1. A community shared solar electric generation system, or other renewable electric generation system, or community shared BESS, which 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 and demand flexibility Energy Design Rating required to comply with the Standards, as calculated according to methods established by the Commission in the Residential ACM Reference Manual.

  2. Compliance demonstration requirements for performance standards. A. 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 which demonstrates, using an approved calculation method, that the building has been designed so that its energy consumption does not exceed the standard design energy budgets for the applicable climate zone. Exception to Section 150.1(b)2A Multiple orientation: A permit applicant may demonstrate compliance with the energy budget requirements of Section 150.1(a) and (b) for any orientation of the same building model if the documentation demonstrates that the building model with its proposed designs and features would comply in each of the four cardinal orientations.

  B. Field verification. When performance of installed features, materials, components, manufactured devices or systems above the minimum specified in Section 150.1(c) is necessary for the building to comply with Section 150.1(b), 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. i. 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 150.1-A or specified for the standard design, the installed system shall be field verified in accordance with the procedures specified in the applicable sections of Reference Residential Appendix RA3.4. ii. **Variable capacity heat pump (VCHP) compliance option.

• § 150.1 Medium relevance — show source text

  Exception 1 to Section 150.1(c)11: Building integrated photovoltaic panels and building integrated solar thermal panels are not required to comply with the minimum requirements for aged solar reflectance and thermal emittance or SRI. Exception 2 to Section 150.1(c)11: Roof constructions with a weight of at least 25 lb/ft [2] are not required to comply with the minimum requirements for aged solar reflectance and thermal emittance or SRI. 12. Ventilation cooling. Single-family homes shall comply with the whole-house fan (WHF) requirements shown in Table 150.1A. When a WHF is required, comply with Subsections A, B and C below. A. Have installed one or more WHFs whose total airflow cfm is equal to or greater than 1.5 cfm/ft [2] of conditioned floor area. Airflow cfm for WHFs shall be determined based on the airflow listed in the Home Ventilating Institute Certified Products Directory. B. Have at least 1 square foot of attic vent free area for each 750 cfm of rated whole-house fan airflow cfm, or if the manufacturer has specified a greater free vent area, the manufacturer’s free vent area specifications. Exception to Section 150.1(c)12B: WHFs that are directly vented to the outside. C. Provide homeowners who have WHFs with a one page “How to operate your whole-house fan” informational sheet. Exception to Section 150.1(c)12: New dwelling units with a conditioned floor area of 500 square feet or less shall not be required to comply with the WHF requirements. 13. HVAC system bypass ducts. Bypass ducts that deliver conditioned supply air directly to the space-conditioning system return duct airflow shall not be used.

  14. Photovoltaic requirements. All single-family residential buildings shall have a newly installed photovoltaic (PV) system or newly installed PV modules meeting the minimum qualification requirements specified in Joint Appendix JA11. The annual electrical output of the PV system shall be no less than the smaller of a PV system size determined using Equation 150.1-C, or the total solar access roof area (SARA) multiplied by 18 for steep-sloped roofs or multiplied by 14 for low-sloped roofs.

  2025 CALIFORNIA ENERGY CODE 181

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

  SINGLE-FAMILY RESIDENTIAL BUILDINGS—PERFORMANCE AND PRESCRIPTIVE COMPLIANCE APPROACHES

  A. SARA includes the area of the building’s roof space capable of structurally supporting a PV system, and the area of all roof space on covered parking areas, carports and all other newly constructed structures on the site that are compatible with supporting a PV system per Title 24, Part 2, Section 1511.10.

  B. SARA does NOT include:

  i. Any roof area that has less than 70 percent annual solar access. Annual solar access is determined by dividing the total annual solar insolation, accounting for shading obstructions, by the total annual solar insolation if the same areas were unshaded by obstructions. For steep slope roofs, only shading from existing permanent natural or manmade obstructions that are external to the dwelling, including but not limited to trees, hills, and adjacent structures, shall be considered for annual solar access calculations. For low slope roofs, all obstructions, including those that are external to the dwelling unit, and obstructions that are part of the building design and elevation features shall be considered for the annual solar access calculations.