IES-VE User Forum

For the daylight Autonomy Calculations in Radiance, under what sky conditions is the Annual Average Lux for Occupancy calculated? (UDI Usefull Daylight Illuminance Process).

"John Mardaljevic* and Azza Nabil":
This method of daylight illuminance modelling we
call ’climate-based’ since the (hourly) sun and sky conditions are founded on values from annual
climate datasets (e.g. direct normal irradiance and global horizontal irradiance from TMY2 files).

Is this also the calculation basis for IESVE UDI?

Another question is about the output results for the DA.

After processing the results we get this "% Annual UDI>......for DA" and "% Annual UDI>...... for Occ 8:00-16:00". (this is an example)

For the second one with the occupancy it is clear that it is based on the hourly period that is selected.
Does the first one, related to the DA, take also the occupancy timetable or does it consider the whole period simulated (like the holiday profile)?

At the IESVE Facebook there is a video presentation with this new features where a manual is presented in pdf form concerning those new daylight simulations.
https://www.youtube.com/watch?list=UUjC ... l3Ok4ieS7U

Where can someone download that. It should have been available.

Thank you in advance.

I have a PDF of a document called Priority for School Buildings Programme: Daylighting Criteria – DA and UDI in RadianceIES which I think is what you are looking for. Pretty sure I downloaded it from the user guide section of the IES website. It's really difficult to find the right thing on there at the moment, so I can't actually see it! Happy to email it to you if you can't find it.