Utilities, interconnection, and billing

What this topic covers

The utility is a separate approval authority with its own rules, tariffs, and timelines. Solar,
battery, and EV-charger projects each interact with it differently: interconnection for
generation, service and metering for charging, and rates for both.

Which authority usually controls

1. Utility tariff and interconnection rules — the filed rules that govern connecting
   generation or load (for example, California's Electric Rule 21 or Texas PUC Substantive Rule
   25.211).
2. Public utility commission — the state body that approves tariffs and hears utility
   complaints.
3. Federal rules where they apply — PURPA-related interconnection standards (18 CFR Part 292)
   for qualifying facilities.

Common questions

• Which approval comes first: permit, HOA, or utility?
• What is an interconnection application and a permission-to-operate?
• How do net metering, successor programs, and export limits work now?
• What do I do if the utility's program terms changed after my application?

What is still controlled locally or privately

A utility approval does not replace a permit or HOA approval, and a statewide solar rule does not
rewrite the utility's filed tariff. Program terms — rates, export compensation, metering, and
effective dates — are set by the tariff and change over time; the current filed version controls.

Common mistakes

• Starting work before the utility's application and approval steps are understood.
• Assuming net metering terms from an old article or old tariff still apply.
• Confusing the utility's permission with the building department's inspection.