How many solar PV panels does it take to make the installation of a PV system worthwhile… 12! A typical solar PV panel is 250-320 watts and the smallest system we would normally recommend is about a 3000-watt system, or 12 standard 250w panels. The infrastructure cost to install a PV system is fairly consistent up through 40 panels so with a very small system the cost per watt is higher and with less than 12 the economics may not be enough of a reason to install… but other factors may come into play: unreliable grid power, or no grid power; desire to be green; expandable for future needs; etc. An “average” single family needs a 6-8kw system to offset their electric usage. Though it is common for homes to need larger systems in the 10-15kw range if they are heavy users of electricity. Typical reasons for this are: hot tub, air conditioner, growing children, additional refrigerators, significant outdoor lighting, and many others.