RileyDylan Posted December 22, 2020 Share Posted December 22, 2020 PVsyst v6.84: I am importing measured irradiance data from a tilted global POA pyranometer (GlobInc aka GPI). I would expect Mod GlobInc to exactly align with the Mes GlobInc that I am importing; however, this is not the case. The first measured GlobInc value is 446.7 W/m^2. Upon importing, I look at the modeled GlobInc value at the same timestamp. GlobInc (Hay model) for the same tilt and azimuth is 416.0 W/m^2. So, there is a 7% deviation b/w Mes and Mod GlobInc at this timestamp (at times the deviations are larger than 7%) The deviations are notably larger at the edges of the day (morning/afternoon) compared to around solar noon. I have set PVsyst to use the Hay transposition model per the following post: Another note: For both Hay and Perez, it reports albedo = 0.2 for GlobInc; however, there is no option to define albedo when importing custom measured irradiance. Should albedo be a user input to the custom data import tool? Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now