LB Cumulative Sky Matrix

Hey everyone,

I’m trying to calculate different shading factors using different types of geometry and the components “LB Sky Matrix” and “LB Incident Radiation”. I wanna make it so the user can choose to get monthly values (A list of 12 shading factors) and hourly values (a list of 8760). Maybe daily as well. My problem is that when I input a list of hoys, for 0…8759 (So every hour of a year), into the sky matrix and the into incident radiation the results are cumulative. So I get one total value for the whole year and not one value for every single hour. I can fix this by grafting my list and creating the skymatrix for every single hour 8760 times, but it takes too much time. I’m really hoping there is an easy fix since I need the hourly values for precise analysis further on. I hope I made myself clear - otherwise please just ask. I can’t link my file since I’m new here - I hope it makes sense. :slight_smile:

Thank you in advance!

PS: I tried uploading the files to this post - I hope that is okay:

Magnus R.

Hey @MagnusRathenborg ,

If you need hourly irradiance values instead of cumulative radiation, you have two (maybe 3) options:

  1. If you are not concerned about context shading falling on a particular surface, you can use the LB Directional Solar Irradiance component to get a hourly data collection of Irradiance falling on a surface of a given altitude and azimuth. This is very fast (practically real time).
  2. If you’re interested in accounting for context and you only need cumulative radiation for each month, you can use the LB Real Time Incident Radiation component to post-process the intersection matrix that you get out of the Incident Radiation component. You just have to create a Cumulative sky matrix for each month and then, if you plug them into this “Real Time” component, the calculation will be much faster than plugging a bunch of sky matrices into the Incident Radiation component.
  3. If you need the state-of the-art, then you should use the HB Annual Irradiance recipe. This will compute hourly irradiance at a set of points and you can parse those results into Grasshopper using various components under the 4 :: Results tab.
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