Photovoltaic system to microgeneration and photovoltaic systems, and the US UL4703 standard, in subject 4703 ""Photovoltaic Wire"". A solar tracking system tilts a solar panel throughout the day. Depending on the type of tracking system, the panel is either aimed directly at the sun or the brightest area of a partly clouded sky. Trackers greatly enhance early morning and late afternoon performance, increasing the total amount of power produced by a system by about 20–25% for a single axis tracker and about 30% or more for a dual axis tracker, depending on latitude. Trackers are effective in regions that receive a large
Nominal power (photovoltaic) resistive load on the module between an open and closed circuit (between maximum and minimum resistance). The highest power thus measured is the 'nominal' power of the module in watts. This nominal power divided by the light power that falls on a given area of a photovoltaic device (area × 1000 W/m) defines its efficiency, the ratio of the device's electrical output to the incident energy. The nominal power is important for designing an installation in order to correctly dimension its cabling and converters. If the available area is limited the solar cell efficiency and with it the nominal power