Create dynamically adjustable louvers/fins for EnergyPlus

Hi guys!

I’m currently working on a large building project with a large WWR where the architects would love to incorporate external shading into the architecture. My task is to investigate pros/cons on both thermal comfort and energy consumption for different shading devices. At this point, they’re mostly interested in dynamic vertical louvers/fins (see reference below).


However, I can see that the EPWindowShade component only supports venetian blinds, roller shades and switchable glazing. And it doesn’t look like the SHDDesigner component will allow me to rotate louvers dynamically during a simulation either.

I’ve currently spent hours trying to search on both HydraShare, this ladybug forum and the grasshopper forum, but can’t find any debates on dynamic louvers/fins. Drawing the louvers is obviously not the problem, but how can I make simulations where the louvers rotate according to a set control?

Any help or redirection would be very much appreciated! Thanks in advance!

Best regards,

Hi @marped,

You could try the following workflow. (It is a bit a work around)
Define 3, 4, 5 or more angles and create for each angle a shade schedule and put them after each other.

Hi Erik

I do understand you’re thought here. You want to preset a number of positions for the lamellas and chose when they are “active” at a given time by assigning a set of schedules. But this still leaves behind the problem of knowing when the lamellas need to have a certain angle.

As I see it, the only solution is as follows:

Conduct a whole year daylight simulation to register when illuminance levels on the exterior window surface exceeds as given threshold level.That can be turned into a list of hourly true/false indexes for the whole year. Now I can know when the shading should be activated. By with lamellas, the shading does not have a simple on/off function like blinds. You need to define the rotation of the lamellas.
This could be solved mathematically by taking in the azimuth of the sun. You might chose that the lamellas should rotate 10 degrees of the suns azimuth. Before noon, the lamellas should turn right and after noon they should turn left to block out the sun. All this information should then be converted into schedules with hourly data which don’t contradict one another, which would be extremely time intensive.

Furthermore, schedules should then be made seperately for the east, south and west orientations, as illuminance levels differ depending on the orientation of the investigated surface.

So my method is clearly not at all feasible, so I’m very open to suggestions xD
@chris would you maybe have some suggestions here?

Hi @marped,

It will be partly as you explained. However some parts can be made more simple:

This is not the case. You can simply ad to all shade generators the same shade control type and set point. For each window and orientation this will be calculated.

These scedules you can generate directly from the EPW file. If take steps of 10 degrees you will need 18 schedules. If you take bigger steps you will need less schedules.

As all different orientations are related to each other, you can simply define for each timestep a set of orientaions based on the facade orientation. This will save you time and make the script less complex.

I agree it is a bit a work around.

Hi, Erik
I am trying to construct the angles of sunshade blinds for all four seasons of the year. How can I divide the year into four seasons using a schedule and control the rotation angles of the blinds separately?

Also assuming that the winter season is set to December 1 to February 28 using LB AnalysisPeriod, with December 31 spanning in between, will radiance be able to correctly identify this time period when performing the calculations, and does it need to be divided into two parts, December 1 to December 31 and January 1 to February 28, for separate calculations? (131.1 KB)

Best regards,

in daylight simulation there is no any set point to control the dynamic shading but recently the dynamic workflow for radiance has been developed to simulate the dynamic object in terms of a annual schedule.

follow this discussion to realize more