This engineer-oriented part is aiming to perform a thorough system design using detailed hourly simulations. This level offers to the user: A large database of PV components, location and meteorological sites. Definition of the plane orientation (with possibility of tracking planes, double-orientation or shed/sun-shields mounting). An expert system to facilitate the PV system layout definition. Detailed parameters allowing fine effects analysis, including thermal behaviour, wiring and mismatch losses, real module quality loss, incidence angle losses. Horizon definition for "far shading" calculations. A 3-D CAO tool for "near shading" detailed studies. A detailed economic evaluation performed using real component prices, additional costs and investment conditions, in any currency. Condensed result forms which summarise all system parameter and the most significant result plots and tables for one given simulation. These forms are readily available on the printer, or can be inserted in documents through the clipboard. Other detailed results available for several dozens of simulation variables, which may be displayed in monthly, daily or hourly tables or graphs, printed or transferred to other software. The 3-D CAO tool The 3-D CAO tool allows the user to draw the geometry of the complete system. It computes a shading factor for beam component as a function of the sun's position. The shading for the diffuse is taken into account using an integral of the shading factor over the sky portion "seen" by the array. It is also possible to partition the array in order to evaluate the electric losses due to the string layout. Animation over a whole chosen day clarifies the shading impact of a given situation.