Looking at the Engineering reference there is an explanation of using different models for the design day solar calculation. However, during an annual simulation, which values are used for I_b, I_h, and I_g values for the equation 5.67 in Engineering Reference? I have put the link to the equation here. https://bigladdersoftware.com/epx/docs/9-5/engineering-reference/shading-module.html#solar-gains-000 Does EnergyPlus run a model used in the design day calculation? or use the radiation data from the weather file? Like "Direct Normal Radiation", "Diffuse Horizontal Radiation"..?
Id be grateful if you could clarify.
