The interconnection process for residential solar can take anywhere from two to four weeks on average, depending on your utility company and system size. The cost for interconnection can depend on your utility, your home's location in relation to the electric grid, and your solar. Interconnection is the process by which a solar customer applies for and receives permission from the local utility company to connect to the utility grid. If you're working with a professional solar company like Palmetto, they will likely take care of the interconnection process on your behalf. This two-phase procedure includes authorization to install (reviewing system plans) and authorization to operate (inspecting the completed. Professional Installation is Critical: Grid-tied solar systems require licensed electricians and multiple permits, with the interconnection process typically taking 2-8 weeks and costing $200-$2,000 in fees alone. During this period, an inspector will check the quality of the installation, including the positioning of the panels, the integrity of the electrical connections, and. How soon until those rooftop panels are soaking up the sunshine, feeding clean energy to your home, and slashing your power bills? The good news is that installing the panels on your roof only takes a day or two.