Distributed Energy ResourcesIslands and MicrogridsBlack StartAdditional InformationSolar DER can be built at different scales—even one small solar panel can provide energy. In fact, about one-third(link is external)of solar energy in the United States is produced by small-scale solar, such as rooftop installations. Household solar installations are called behind-the-meter solar; the meter measures how much electricity a consumerSee more on energy.govinmab [PDF]
Standard size of distributed photovoltaic panels - inmab
The goal here is to get to the average solar panel size by wattage. You can find typical dimensions of 100W, 150W, 170W, 200W, 200W, 220W, 300W, 350W, 400W, and 500W solar