Determining Compliance

Step 1: Determine PV System Size

The required solar PV capacity can be established based on the building's conditioned floor area and the applicable PV capacity factor.

PV Capacity = Conditioned Floor Area × Applicable PV Capacity Factor

Alternatively, the available rooftop area may be evaluated based on the portion of the roof with sufficient solar access for PV installation.

Step 2: Determine Energy Storage Capacity

Once the PV system size has been established, the corresponding battery storage capacity can be determined using the applicable energy storage sizing factor.

Storage Capacity = PV System Capacity × Applicable Storage Factor ÷ √(System Efficiency)

Certain projects may qualify for exceptions where energy storage is not required. These may include conditions such as:

  • The proposed PV system is below the applicable percentage of the calculated PV requirement.
  • The resulting energy storage requirement falls below the applicable minimum threshold.
  • The building falls below the applicable floor-area threshold.

Step 3: Verify JA12 Performance Requirements

Where applicable, the energy storage system must satisfy the required performance criteria under California's JA12 standard.
Key considerations include:

  • Minimum energy storage capacity: 5 kWh
  • Round-trip efficiency: 80% or greater
  • Cycle life: 4,000 cycles, or an applicable 10-year warranty with specified end-of-life performance
  • Battery system listing: UL 1973 / UL 9540
  • Inverter listing: UL 1741 / UL 1741 SA, as applicable

Actual sizing and compliance requirements should be verified against the
current California Energy Code and applicable project-specific requirements.