I suspect that the easier method would be to isolate the output variables that give you this information. These output variables will provide the amount of solar radiation transmitted through the window, which is added as heat to your building zone.
Output:Variable,*,Zone Windows Total Transmitted Solar Radiation Rate,hourly; !- Zone Average [W]
Output:Variable,*,Zone Exterior Windows Total Transmitted Beam Solar Radiation Rate,hourly; !- Zone Average [W]
Output:Variable,*,Zone Exterior Windows Total Transmitted Diffuse Solar Radiation Rate,hourly; !- Zone Average [W]
Output:Variable,*,Zone Windows Total Heat Gain Rate,hourly; !- Zone Average [W]
Output:Variable,*,Zone Windows Total Heat Loss Rate,hourly; !- Zone Average [W]
or in terms of energy
Output:Variable,*,Zone Windows Total Transmitted Solar Radiation Energy,hourly; !- Zone Sum [J]
Output:Variable,*,Zone Exterior Windows Total Transmitted Beam Solar Radiation Energy,hourly; !- Zone Sum [J]
Output:Variable,*,Zone Exterior Windows Total Transmitted Diffuse Solar Radiation Energy,hourly; !- Zone Sum [J]
Output:Variable,*,Zone Windows Total Heat Gain Energy,hourly; !- Zone Sum [J]
Output:Variable,*,Zone Windows Total Heat Loss Energy,hourly; !- Zone Sum [J]
To observe the amount of solar radiation incident on an outside, sun-exposed, building surface, you can use the variables:
Output:Variable,*,Surface Outside Face Incident Solar Radiation Rate per Area,hourly; !- Zone Average [W/m2]
Output:Variable,*,Surface Outside Face Incident Beam Solar Radiation Rate per Area,hourly; !- Zone Average [W/m2]
Output:Variable,*,Surface Outside Face Incident Sky Diffuse Solar Radiation Rate per Area,hourly; !- Zone Average [W/m2]
Output:Variable,*,Surface Outside Face Incident Ground Diffuse Solar Radiation Rate per Area,hourly; !- Zone Average [W/m2]
All these variables an more can be found in the EnergyPlus output file with the extension *.rdd
.