The total installation time for a standard 3-kilowatt solar system of about 20 solar panels is usually somewhere between 1 and 3 days. Average labor time is 75 man-hours, which can be further broken down into electrician installation labor (49 man-hours) and non-electrician installation labor (26 man-hours).
However, the time from you deciding to go solar to the solar panels are up on your roof can be longer. The design of the solar system and other lead-up work adds time to the process.
In most places, we`re looking at a couple of weeks, but depending on region, how long it takes to get permits there and how developed the solar market is, it can actually take several months.
The complexity of the solar system can also lengthen the installation process. A solar system with a battery backup is more complex and will add a couple of hours of labor. In many cases, the utility has to set up a bidirectional electric meter for net-metering.
Labor costs average at about 10% of total system costs. Several companies are working to make solar installations more efficient and cheaper. SOLON`s SOLquick flat roof installation “has proven to reduce mechanical installation time by over 85 percent and electrical installation time by 50 percent”, which granted the German solar company the Intersolar Award in June 2012.
You should request a quote to find out how many days or weeks it would be in your situation.