Weird shaded solar radiation per hour output from sunpath shading component


Is the shaded solar radiation per hour output from sunpath shading component the total irradiation which consists of direct, diffuse and ground reflected irradiation (Ipoa: Plane-of-Array Irradiance)?

I have compared the result from the sunpath shading component with the output from radiance analysis component. The result from the faces facing east and west is really weird. The east facade has a significantly higher output than the west facing facade as it shows in the screenshot below:

I am a new user so I can not upload the gh file now. But it is very simple as it shows in the screenshot.
If this is a bug, is there any other way to obtain the hourly data for both total irradiation and direct irradiation with consideration of the context.

Thank you.

Hi @cyster,

If you need the reflections to be considered in your radiation analysis then you need to use radiation option in Honeybee_Grid Based Simulation component.

In your analysis, since only east surface is being analyzed, it looks all red. If you include other surfaces of the box in your simulation, then the east surface will look yellow.

Hi devang,

Thank you for your reply! The analysis I did included both east and west facade which is not shown in the picture. The model does not have any context buildings. As you can see, the irradiation for the east facade is around 1060 kWh per year, while the west is only 305 kWh per year. I have tested this in different locations such as Zurich, Paris, and Osaka, however, the result still does not make sense. It seems the sunpath shading component works fine for the south-facing facade.

What I need is the hourly result (for a year) for total irradiation Ipoa and the direct irradiation Ib with consideration of the context buildings. The ladybug irradiation analysis component does not consider the ground-reflected irradiation Ig which is part of the Ipoa. Is there any other way to do this?

You can share your file. This explain how to do that. Can you please explain what lpoa and lb are? Here’s a sample to run radiation analysis with radiance. (497.8 KB)

Thank you so much for your reply. Here is my script.

hourly (509.7 KB)

Ipoa is the total solar irradiation on a surface (the shaded solar radiation per hour output from the sunpath shading component). It is the sum of direct irradiation from sun Ib, diffuse irradiation from the sky Id,sky, and the ground-reflected irradiation Id,ground. Ipoa = Ib + Id,sky + Id,ground. I need the hourly values of Ipoa and Ib for one year.

I am also trying to do this with honeybee script you provied, it is really helpful. However, is it possible to obtain the hourly value?

You can do the following to iterate through all the hours of the year. (514.0 KB)

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