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diffuse horizontal illuminance

asked 2018-10-01 09:15:44 -0500

duyguzz's avatar

updated 2018-10-01 09:17:53 -0500

hi, I need to determine the median diffuse horizontal illuminance from the sky for the city Istanbul. Therefore, I need to obtain the standardized climate files contain an annual time series of 8760 hourly values for diffuse horizontal illuminance. I have been told that I can obtain these data from Energyplus Weather file. I downloaded the Energyplus program. But I could not find the converter part. I'm trying to do it, but I couldnt be successful. Can you convert these two files?. Therefore, I need to obtain the standardized climate files contain an annual time series of 8760 hourly values for diffuse horizontal illuminance. The file is attached for Istanbul and Ankara cities. Can we get the excel file? Is there a program I can get this data out of the energyplus program? I would be glad if you help.

Thanks in advance!

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answered 2018-10-01 11:15:21 -0500

Diffuse horizontal illuminance (lux) is (in theory) field 15 in a properly-formatted EPW weather file; the files are CSV data, so if you open it in Excel you can read it in as CSV, and you will "have" an Excel file when you're done. Does this make sense?

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hi, I didn't understand what you said. What is 15? Excel enough but i can't get lux valuable chart Iwec file is available in energy plus. Are diffuse horizontal illuminance (lux) values available in this file ? How do I get a csv file? Thanks in advance!

duyguzz's avatar duyguzz  ( 2018-10-03 14:52:19 -0500 )edit

What I meant is that field 15, the fifteenth element in the data array, is the value you seek, if you are looking at an EnergyPlus weather data file (.epw file). I don't know much about the IWEC format, but you can get epw files that were translated from IWEC here: THese files are in csv format.

rpg777's avatar rpg777  ( 2018-10-04 11:25:14 -0500 )edit

I would ask you, Can you give me Ankara and Istanbul (Türkiye) lux valuable chart?Is there a simple way to find it? i can't use the program at all. My results are necessary for my thesis. Can you give me the output format?

duyguzz's avatar duyguzz  ( 2018-10-04 15:13:28 -0500 )edit

The simple way is to follow the link I included in my comment, above. Unfortunately, the website is having technical difficulties at the moment, but eventually, the url should take you to a page with a search engine, and you could e.g. look for Istanbul:, and download from there.

rpg777's avatar rpg777  ( 2018-10-04 15:46:46 -0500 )edit

As I said in my first article, I have this file. Does this file have lux data? If so, how does it open in the excel file?

duyguzz's avatar duyguzz  ( 2018-10-05 00:37:26 -0500 )edit

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Asked: 2018-10-01 09:15:44 -0500

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Last updated: Oct 01 '18