By Brett Duguay | BD Electrical & Solar | September 30, 2026
The panels are installed. The wiring is complete. The local inspection has passed. Why might a solar project still be waiting to operate?
Because construction and utility authorization are separate milestones. Interconnection is the process for determining how a generating system can connect safely to the electric grid. It can affect the project’s size, cost, equipment, and schedule long before installation starts.
A national issue with a local version
Large generation projects can wait for studies and transmission upgrades before they can connect to the grid. A home or commercial rooftop usually follows a distribution utility’s process, rather than the same regional study path used by a major power plant. The paperwork and timelines differ, but the engineering question is similar: what changes when this system begins exporting power?
Power can flow out of a solar-equipped property as well as into it. The utility reviews the proposed equipment and how it interacts with the local network. A sunny roof alone cannot answer that question.
What the utility is evaluating
The review may consider transformer loading, voltage, protective equipment, and other generation connected to the same circuit. A project that passes the applicable screening criteria can take a simpler path. A project that does not may require additional study or physical upgrades.
These are site-specific questions. Two similar buildings on different circuits can receive different results. A nearby project’s approval is useful context, but it is not a promise that your property will receive the same treatment.
Export limits can change the design
Sometimes the conversation becomes how much power the system may send to the grid, rather than how many panels can fit on the property. An approved power-control system may be part of an export-limited design.
For example, consider an illustrative array capable of producing more power than the utility permits it to export. Some output can serve the building directly; a compatible battery may absorb some energy when it has room. If neither can use the remaining output, the system may need to reduce production. The annual effect depends on the building’s demand and the control settings.
An export cap therefore belongs in both the electrical design and the production estimate. It should never be treated as a paperwork detail that has no effect on performance.
Build the schedule around actual milestones
A useful schedule identifies the application, any required study, the utility’s approval to proceed, equipment procurement, installation, inspection, and permission to operate. Some activities can overlap. Others depend on an approval or a utility crew.
If a transformer or other utility work is required, the project needs an allowance for that work and a clear assignment of responsibility. A contractor can manage submissions and follow up; it cannot promise a utility-controlled completion date that has not been confirmed.
Questions to ask before committing
- Has the proposed system been submitted to the utility?
- Are upgrades or studies confirmed, possible, or still unknown?
- Does the production estimate include any export restriction?
- Which payments and construction steps depend on utility milestones?
BD’s commercial energy planning starts with the electrical connection as well as the array. Identifying these constraints early gives an owner a better basis for deciding whether to proceed, resize, or revise the project.
Further reading: Massachusetts utility interconnection guidance.