May I ask whether the coefficients (sky clearance and brightness) of the Perez model would be adjusted when I chose a different location (weather profile)?
Or only the sun hour and other climatic profiles would change if I chose a different location.
We call the gendaylit program to handle all of this. The link describes all of the assumptions in the model parameterization reasonably well.
I have tried to read the document you mentioned. However, I cannot find the part that explains whether the coefficients are adjusted according to the location. It only stated that the data are from radiometric measurement centres.
I think the relevant part is here:
The atmospheric conditions are modelled with the Perez et al. parametrization (see Solar Energy Vol. 44, No 5, pp. 271-289, 1990), which is dependent on the values for the direct-normal and the diffuse-horizontalirradiances. The three parameters are epsilon, delta and the solar zenith angle. "Epsilon variations express the transition from a totally overcast sky (epsilon=1) to a low turbidity clear sky (epsilon>6); delta varia-tions reflect the opacity/thickness of the clouds". Delta can vary from 0.05 representing a dark sky to 0.5 for a very bright sky.