Rooftop photovoltaic power station Rooftop photovoltaic power station A rooftop photovoltaic power station, or rooftop PV system, is a photovoltaic system that has its electricity-generating solar panels mounted on the rooftop of a residential or commercial building or structure. The various components of such a system include photovoltaic modules, mounting systems, cables, solar inverters and other electrical accessories. Rooftop mounted systems are small compared to ground-mounted photovoltaic power stations with capacities in the megawatt range. Rooftop PV systems on residential buildings typically feature a capacity of about 5 to 20 kilowatts (kW), while those mounted on commercial buildings often reach 100 kilowatts or more.
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