DAYSIM: 0% Daylight Factor across all points


I have previously used DAYSIM to produce some calculations. However the results are no longer repeatable.

Despite getting values for UDI and DA etc. all the daylight factors are now 0.

My suspicion is that the DAYSIM installation has clashed with a RADIANCE installation and the system paths are confused.

I have tried uninstalling everything and just reinstalling Daysim 3.1e.

This produces the following system paths:

PATH: ;C:\Daysim\bin_windows\;C:\Radiance\bin\;C:\DAYSIM

RAYPATH: ;C:\Daysim\lib\;.C:\Radiance\lib\;.

As C:\Daysim\lib is in RAYPATH, I can’t see what is causing the problem

Thanks for your help


Ross Thompson

Senior Sustainability & Energy Engineer

T: 01865 864500

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