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
Localization of a module of flatness in algebraic geometry, saying in particular that the inclusion of the open set Spec("S""R") into Spec("R") (see spectrum of a ring) is a flat morphism. In terms of localization of modules, one can define quasi-coherent sheaves and coherent sheaves on locally ringed spaces. In algebraic geometry, the quasi-coherent "O"-modules for schemes "X" are those that are locally modelled on sheaves on Spec("R") of localizations of any "R"-module "M". A coherent "O"-module is such a sheaf, locally modelled on a finitely-presented module over "R". Any textbook on commutative algebra covers this topic, such as: Localization of a module In