What is interconnection and why does it matter?
A grid-connected solar system is wired to your home's electrical service, which is connected to the utility's lines. When your panels produce more power than your home is using, that power can flow back to the grid. The utility needs to know that the equipment is safe, that it will shut off during an outage to protect line workers, and that its meter and records match your system.
Interconnection is how that happens. It is a formal application and approval process run by the utility, separate from the building and electrical permits issued by your local jurisdiction. Turning a system on before approval is not allowed and can create safety and billing problems.
What are the general steps?
Exact steps and forms are set by Idaho Power and can change, but most residential and small commercial projects follow a similar path.
- Site review and system design, including the electrical connection point and any panel work
- Interconnection application submitted to Idaho Power with system details and a single-line diagram
- Utility review of the application, which may include questions or requested changes
- Local electrical permit and, where required, building permit
- Installation of the panels, racking, inverter and electrical equipment
- Local inspection of the completed work
- Utility verification steps and any meter changes
- Permission to operate, after which the system can be turned on
What goes into the application?
The application describes the system and how it connects. That usually includes the property and account information, the size of the system, the equipment being used such as panels and inverters, and an electrical diagram showing how the system ties into your service. The homeowner is typically the applicant or signs to authorize the installer to apply on their behalf.
Getting the electrical details right the first time helps avoid delays. Because the connection point, disconnects and panel capacity are electrical design questions, an installer who is also the electrical contractor can prepare this part of the application from first-hand knowledge of your service.
How does the panel and service fit in?
Every solar system connects through your electrical service. Sometimes the existing panel has the capacity and space for the solar connection. Sometimes the panel needs to be upgraded, or the system needs a different connection method. These choices affect what is shown on the interconnection application and the permit drawings.
Identifying panel work early keeps the application accurate and avoids changes after the utility has already reviewed it.
How long does interconnection take?
It varies. Timing depends on Idaho Power's review workload, whether the application needs revisions, local permitting and inspection schedules, and any equipment or metering changes. The physical installation is often the quickest part of the overall project. A good installer gives you a realistic timeline for each stage and keeps you updated, rather than a single date that ignores the steps outside their control.
What about billing, credits and rates?
How excess solar power is measured and credited on your bill is set by Idaho Power's current programs and regulatory decisions, and those have changed over time. We do not quote rates or credit amounts, because they can change and depend on your account. Before you commit to a system, read Idaho Power's current information for customer generation and ask them directly how it would apply to your account. Base your decision on current, confirmed program details.
What happens after the system is turned on?
Once you have permission to operate, the system is switched on and monitoring is set up so you can see production. Keep a copy of the approval and system documents with your home records, since you will want them for future service, insurance and any eventual sale. If you later add batteries, more panels or other changes, check with your installer whether the change requires updating your interconnection with Idaho Power.