Solar systems cannot just be switched on after install. There are two approvals: your city or county, and your utility.
What are the steps to turn on solar?
- Design and permit. The installer submits plans to your city or county. California requires local agencies to offer streamlined permitting for small residential rooftop solar.
- Interconnection application. The installer applies to your utility to connect the system to the grid.
- Install of panels, inverters or microinverters, rapid-shutdown equipment, disconnects and the panel connection.
- Inspection by the city or county building department.
- Permission to Operate (PTO). After the final inspection, the utility reviews it and gives written permission to turn the system on. Turning it on before PTO can violate your utility agreement.
What is rapid shutdown?
Rooftop solar must have a rapid-shutdown function so firefighters can de-energize the conductors on the roof. There is usually a labeled initiation switch near the service equipment.
How long does it take?
It varies widely with the permit office and the utility queue, from a few weeks to a few months. Ask your installer for local, recent timelines rather than a national average.
Common questions
What is PTO for solar?
PTO stands for Permission to Operate. It is written approval from your utility to turn on a grid-connected solar system after the local inspection passes.
Can I turn on my solar before PTO?
You should not. Operating before your utility grants Permission to Operate can violate your interconnection agreement.
General information for California homes under the California Electrical Code (based on the NEC). Local rules and inspectors can vary. Not a substitute for an on-site inspection. Never work inside a panel, at the meter or on live circuits.