Solar radiation through windows

Diffuse solar transmission - The transmitted solar radiation through the glazing from diffuse sky and ground irradiation. 

Direct solar transmission - The transmitted solar radiation through the glazing from direct sun irradiation.

Sunshine duration -  A value that equals one when there is direct irradiation on the window and otherwise zero. By open it as a separate diagram and changing the type to "Duration", the number of sunshine hours in the period can be displayed. To get sunshine duration for a zone with windows in different directions, open a new diagram with sunshine duration for all the windows and evaluate the duration time manually.      

Total solar energy transmission - The sum of direct and diffuse solar transmission + indirectly (as heat) transmitted solar energy from absorption in the glazing.