Direct Sun only calculation

Hi @Bing ,

It’s a little more complicated than what you describe. The direct sun doesn’t really come “free” with annual daylight since it can greatly increase the simulation time when running thousands of sensors. I don’t want to get into all of the details of exactly why this is the case but it’s related to us being unable to use binary formats for the illuminance matrices when the direct illuminance is output.

Also, we really don’t want people using this type of direct illuminance out of annual-daylight for computing ASE since it’s not coordinated with the LM standard used by LEED. We will be adding a dedicated recipe for ASE soon that will be capable of outputting blind/shade control schedules that can be applied to the Annual Daylight results to get LM-compliant sDA and ASE. So, if what you actually need is ASE, then using this dedicated ASE recipe is going to be my ultimate recommendation for your case. Using Annual Irradiance with visible_ right now is just to give you a temporary workaround.

Also, please don’t use -ab 0 for annual-daylight right now as it can result in negative illuminance values (given how the illuminance matrices have to be added/subtracted from one another). I still have yet to add a check that prevents the use of -ab 0 for annual-daylight.

Totally understand your concern on ASE. Saw discussion on other posts. No this is all good to me.

And thanks for the tips of ab0 calc. I recall I saw it before now as you mentioned it.

Looking forward to the LM-compliant sDA and ASE. We are doing manual post-processing for now and happy to have a tool for that of course.

Thanks Chris.

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