The short answer
- Your installer pulls a building or electrical permit from your city (or county, outside cities) before connecting to the utility.
- State law caps the permit fee at $450 plus $15 per kW above 15 kW for home solar (Gov. Code §66015, in effect until 2034).
- Cities over 5,000 people must offer instant online permits for home solar and paired batteries up to 38.4 kW (SB 379). About 132 SoCal cities use SolarAPP+ for this.
- Cities may review solar only for health and safety, and may deny a permit only with written findings (Gov. Code §65850.5).
Instant permits (SB 379 and SolarAPP+)
Gov. Code §65850.52 requires an "online, automated permitting platform, such as SolarAPP+" that issues permits in real time for home solar and paired storage up to 38.4 kW. Cities over 50,000 people had until Sep 30, 2023; smaller ones until Sep 30, 2024. Cities under 5,000 people, and counties under 150,000 with their cities, are exempt. The CEC tracks what each city reports on its SB 379 dashboard.
Big jurisdictions that aren't on the SolarAPP+ list, including the City of Los Angeles, the City of San Diego and LA County, use their own systems.
City of Los Angeles
LADBS's online express permit covers rooftop systems up to 10 kW on 1–2 family homes (single-phase, a panel of 225 A or less, up to 2 string inverters). An AC-coupled battery up to 10 kW can go on an express permit too but needs a Fire Department plan check. Larger systems go to plan check through ePlanLA (LADBS bulletin, May 2024).
City of San Diego
Contractors can self-issue permits without plan review for systems up to 38.4 kW built to Information Bulletin 301, with batteries up to 38.4 kWh (20 kWh per unit) and panel upgrades up to 320 A. The first inspection is $275.80 (May 2026); the system can't be turned on until SDG&E approves (City of San Diego, IB 301).
Batteries and fire code
Each home battery unit is limited to 20 kWh, and batteries can't go in bedrooms or closets opening into them. Total limits depend on location: 40 kWh in a utility closet, 80 kWh in an attached garage, more outdoors under the 2025 California Residential Code (effective Jan 1, 2026). Garage installations need impact protection.
After the permit
An inspector signs off the work, then the utility grants permission to operate. How long approval takes.
Checked against official sources on Oct 1, 2026. Sources are linked in the text. Not legal, tax or financial advice.