Interconnection
The utility approval process that allows your solar system to connect to the electrical grid — a required step before your system can export power or earn net metering credits.
Interconnection is the formal utility approval process for grid-tied solar. Before a solar system can legally send power to the grid, the local utility must review the installation, ensure it meets technical standards, and grant permission to operate (PTO). The process involves submitting an interconnection application, utility technical review, inspection coordination, and final approval.
Timelines vary dramatically: some utilities process applications in 2–4 weeks; others take 3–6 months. Overloaded distribution circuits can trigger expensive "grid upgrades" the homeowner may be required to pay for. The interconnection process is distinct from the permit process with local government — both are required.
Net metering enrollment occurs during or after interconnection. Your utility will replace your standard meter with a bidirectional meter that tracks both consumption and export. "Permission to Operate" (PTO) from the utility — not just local permit approval — is the signal to turn on your system and begin earning net metering credits. Turning on before PTO can result in fines and system shutdown.
Real-World Example
The panels passed the city inspection in week 4, but the utility's interconnection queue was so backlogged that PTO wasn't granted until week 14 — the system sat fully installed and idle for 10 weeks while the homeowner continued paying full electricity bills.