Any correlation between Eppy not working when Pollination is installed?

hi @mostapha

We’ve been trying to do as much as possible on Rhino plugin, then to bring the model onto GH to specify more elements and advanced scripts.

We are used to use Eppy through GHC_python to set the Ground Heat transfer, to modify IDFs. It has happened in the office that on the computers where we have installed Pollination, this error pops up. I’m not assuming there is a direct correlation but we have really been scratching our heads and couldn’t find any explanation.
We just observed that :

  • computer with pollination Eppy doesn’t work,
  • computer without pollination Eppy works.

Have you experienced anything like this?

Hi @olivierdambron,

The error is because Eppy cannot find the EnergyPlus IDD file in the EnergyPlus that is installed as part of OpenStudio. It is not really related to Pollination, I would say. My guess is that the other computer doesn’t have OpenStudio installed or it is not high in the system PATH.

I downloaded the latest version of eppy and it gives a better error message.

eppy.modeleditor.IDDNotSetError: IDD file needed to read the idf file. Set it using IDF.setiddname(iddfile)

You should be able to set the path to the IDD file to where the full version of the EnergyPlus is installed. This one worked for me.

import eppy
from eppy import modeleditor
from eppy.modeleditor import IDF

idf = r"path-to-idf-file.idf"

hi @mostapha

@mmerli who is an Atmos Lab colleague, was not able to post on the forum because it seems that his Pollination account is on hold for another 15 days. Could you help us unlock it?

Regarding the potential correlation in between Eppy and Pollination, he meant to write the following :

Hi @mostapha
I’m jumping in here as I initially found this error. I’ve attempted various solutions concerning eppy, energy+, and GHC_python, but I haven’t identified any other connections apart from Pollination.
Here is the script with the GHC component I’m trying to run.
The first figure shows the component that works properly when Pollination is not installed.

However, after installing Pollination on the machine, the component no longer works, and the error message is perplexing (figure 2).

I can’t make sense of how or whether the installation of Pollination affects the paths or not.
If you have any thoughts on this, kindly let us know.
Thank you


Hi @olivierdambron - Thank you for adding the post. I unsilenced @mmerli’s account.

@mmerli - did you update the eppy installation and modified the code as I pasted above? From the error message, it looks like you are still using an older version.