The average cost of a solar panel installation can vary greatly depending on factors such as the size of the system, location, type of panels, labor costs, and any additional components or upgrades. As of my knowledge cutoff date in September 2021, in the United States, a typical residential solar panel installation can range from $10,000 to $30,000 or more, with an average cost of around $15,000 to $25,000 for a standard system. However, it’s important to note that costs can vary significantly.