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EPW file cannot be processed (custom, purchased weather file)

asked 2020-06-11 20:26:24 -0600

sashadf1's avatar

updated 2020-06-12 12:20:06 -0600

Hi all,

Context: I am trying to run a simulation using PAT/OpenStudio v2.9.0 and ResStock v2.2.4. I have inputed my own weather file into Worker initialization Script field using a dropbox direct download link, I have manually set the seed value in the ruby file run_sampling, and I have manually edited location, location-region, and vintage TSV files to reflect a location specific to the project. I have changed AMY = 1 in location weather year TSV.

I am trying to simulate a region in Georgia. I am using an EPW file that I purchased from WhiteBox Technology I have renamed my EPW weather file from its original download file name (NC_ANDREWS-AP_722177_08.epw) to 0979938_US_GA_Clarke_13059_0-20000-0-72311_33.97_-83.34_NSRDB_2.0.1_AMY.epw so that it is recognized by PAT. Before I did this, I was getting an error that the EPW file did not exist or was not an EPW file.

Currently, I am getting completed datapoint failure messages on all buildings of my simulation. Looking through one of the log text files, I discovered that the error is documented by this message:

[openstudio.EpwFile] <1> Bad start day of week in EPW file '/mnt/openstudio/analysis_3e5d6b81-eafa-4ac6-89ce-5440c92c46cf/weather/0979938_US_GA_Clarke_13059_0-20000-0-72311_33.97_-83.34_NSRDB_2.0.1_AMY.epw' [openstudio.EpwFile] <1> Failed to parse EPW file header '/mnt/openstudio/analysis_3e5d6b81-eafa-4ac6-89ce-5440c92c46cf/weather/0979938_US_GA_Clarke_13059_0-20000-0-72311_33.97_-83.34_NSRDB_2.0.1_AMY.epw' [openstudio.EpwFile] <2> EpwFile '/mnt/openstudio/analysis_3e5d6b81-eafa-4ac6-89ce-5440c92c46cf/weather/0979938_US_GA_Clarke_13059_0-20000-0-72311_33.97_-83.34_NSRDB_2.0.1_AMY.epw' cannot be processed

Any idea what is going on? I am new to OpenStudio and PAT so I don't have a lot of intuition as to why this is happening. Do I have a faulty EPW file? I just downloaded Elements software so that I can edit the EPW file if necessary.

What do "bad start day of week," and "Failed to parse EWP file header" entail?

EDIT: The issue was mispelled day of week in the EPW header! Tuesday was spelled as Tuesdayy!

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I´d check first if it´s an EPW problem, by running a regular E+ or OS model with it - I´ve worked with Whitebox Technologies in the past and always worked well.

If it is an EPW problem, open the EPW with a text editor, like Notepad++ or alike and check the header. I´d compare the header of your EPW to another functional EPW (here there are a lot -

rafael.alonso's avatar rafael.alonso  ( 2020-06-12 03:36:37 -0600 )edit

@sashadf1, please self-answer with your solution.

Eric Wilson's avatar Eric Wilson  ( 2020-06-12 14:34:49 -0600 )edit

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answered 2020-06-12 14:53:54 -0600

sashadf1's avatar

Self-posted solution: The issue here was that the EPW file had a typo: January 1 for 2008, which was the appropriate year for the AMY file, was a Tuesday. The EPW file listed Tuesday as "Tuesdayy" with two y's. The solution was to simply delete one of the extra y's, save the file, rezip the file, reupload to dropbox, and recreate the direct download link to post into Worker initialization Script field.

EPW file before edit:

EPW file before edit

EPW file after edit:

EPW file after edit

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You should probably let WhiteBox Technologies know that they are creating EPWs that may have a typo.

shorowit's avatar shorowit  ( 2020-06-12 15:14:53 -0600 )edit

Sent them an email.

sashadf1's avatar sashadf1  ( 2020-06-12 15:58:55 -0600 )edit

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Asked: 2020-06-11 20:26:24 -0600

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Last updated: Feb 22 '21