The Module Layout is a tool for the description of the PV modules geometrical arrangement in your system, and their interconnections as strings.
This is necessary for an accurate calculation of the electrical effects of the partial shadings of near objects in Si-crystalline modules. It is not suited for electrical calculations with thin film modules, where each cell is a long narrow strip; you should think about its pertinence from case to case.
The Module Layout is the last step of your development for the study of a PV system: it can only be defined after the careful definition of the 3D shadings scene.
Incidentally, this tool is also useful for an easy design of the module wiring organization within your PV system.
This is a very technical aspect of the presentation of your system. Therefore it is not part of the final simulation report, but it can be printed independently.
In this tool, you should import the field areas defined in the 3D shading scene, and fill them with the real modules specified as sub-arrays during the system design, as strings connected to inverter inputs. Therefore both System and Shading 3D scene should be fully defined before completing this part.
The PV modules are distributed on each 3D-subfield area (called "Table"), either in portrait or in landscape. You can specify the spacing between modules.
We define a sub-module as the set of cells protected by one by-pass diode (usually up to around 18-22 PV cells). Each sub-module is supposed to be a row in the module, and the direction of the sub-modules has also to be specified. The electrical shading effects will be be evaluated at the sub-module level.
Each module has to be attributed electrically to a string of the system, i.e. a given MPPT input of a given inverter. The electrical behaviour will be computed according to shadings for each circuit, i.e. the full I/V curve for each MPPT input. The tool allows to visualize the electrical composition of the I/V characteristics and the loss on each MPPT input, for given shading figures.
The electrical calculations are done taking the beam and diffuse components into account. Even when a sub-module is completely shaded (regarding the beam component), there is a remaining diffuse irradiance which ensures a minimum current in this string. The diffuse incident irradiance is coming from all directions, it is supposed homogeneous and to be affected by a constant shading factor, calculated once only for the whole year. Eventual albedo is also evaluated using a constant shading factor.