# \#epw

**URL:** https://discourse.ladybug.tools/tag/epw/2.md

[Latest](https://discourse.ladybug.tools/latest.md) · [Categories](https://discourse.ladybug.tools/categories.md) · [Tags](https://discourse.ladybug.tools/tags.md)

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## [Custom EPW file import in Ladybug Grasshopper from PC folder](https://discourse.ladybug.tools/t/custom-epw-file-import-in-ladybug-grasshopper-from-pc-folder/23663)

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**Author:** [@Anastasiia](https://discourse.ladybug.tools/u/Anastasiia)\
**Replies:** 8\
**Last updated:** [September 16, 2026, 10:17am UTC](https://discourse.ladybug.tools/t/custom-epw-file-import-in-ladybug-grasshopper-from-pc-folder/23663 "2026-09-16T10:17:36Z")

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Hello! I am surviving some kind of a crisis here:) The aim of my research is to compare the two summer temperature scenarios (the current situation VS the R.C.P. 4.5 projection to the 2050). I managed to successfully mo…

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## [Using real-world weather - what to do for Horiz Infrared Rad (Comfort Workflow)](https://discourse.ladybug.tools/t/using-real-world-weather-what-to-do-for-horiz-infrared-rad-comfort-workflow/40485)

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**Author:** [@remyweather](https://discourse.ladybug.tools/u/remyweather)\
**Replies:** 3\
**Last updated:** [June 22, 2026, 10:29pm UTC](https://discourse.ladybug.tools/t/using-real-world-weather-what-to-do-for-horiz-infrared-rad-comfort-workflow/40485 "2026-06-22T22:29:02Z")

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Hi Guys, I am trying to run the LB thermal comfort workflow with real-world weather that I am downloading from open-meteo api ( 🏛️ Historical Weather API | Open-Meteo.com ) to run the workflow with real world weather ra…

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## [Updated climate data for Norway](https://discourse.ladybug.tools/t/updated-climate-data-for-norway/39400)

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**Author:** [@LittleBuddha](https://discourse.ladybug.tools/u/LittleBuddha)\
**Replies:** 0\
**Last updated:** [October 23, 2025, 8:51am UTC](https://discourse.ladybug.tools/t/updated-climate-data-for-norway/39400 "2025-10-23T08:51:03Z")

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There is now a new climate data set for Norway, launched on: https://klimadataforbygninger.no/ There the data can be downloaded per site, and datasheets per site are available. The dataset is also available as a full …

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## [Where to find .epw weather data](https://discourse.ladybug.tools/t/where-to-find-epw-weather-data/375)

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**Author:** [@mostapha](https://discourse.ladybug.tools/u/mostapha)\
**Replies:** 44\
**Last updated:** [September 25, 2025, 10:43am UTC](https://discourse.ladybug.tools/t/where-to-find-epw-weather-data/375 "2025-09-25T10:43:37Z")

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\[This list will be modified over time\] Free resources: The main source is DOE’s website: http://apps1.eere.energy.gov/buildings/energyplus/weatherdata\_about… https://www.energyplus.net/weather One building.com is…

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## [Development: EPW Weather Data Modification Component](https://discourse.ladybug.tools/t/development-epw-weather-data-modification-component/36992)

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**Author:** [@behnammmohseni](https://discourse.ladybug.tools/u/behnammmohseni)\
**Replies:** 4\
**Last updated:** [July 14, 2025, 5:40pm UTC](https://discourse.ladybug.tools/t/development-epw-weather-data-modification-component/36992 "2025-07-14T17:40:52Z")

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Hi @chris @mostapha I hope this message finds you both well. I was wondering if it would be possible to develop a component for EPW weather data interpolation, similar to the one offered by Metronome, a commercial and …

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## [Inconsistency of Model runs between downloaded and local file location for EPW files](https://discourse.ladybug.tools/t/inconsistency-of-model-runs-between-downloaded-and-local-file-location-for-epw-files/36431)

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**Author:** [@MichaelDonn](https://discourse.ladybug.tools/u/MichaelDonn)\
**Replies:** 3\
**Last updated:** [April 17, 2025, 12:42pm UTC](https://discourse.ladybug.tools/t/inconsistency-of-model-runs-between-downloaded-and-local-file-location-for-epw-files/36431 "2025-04-17T12:42:21Z")

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I am pretty sure I am not doing something that is very simple. But I cannot fathom what. I have attached two new weather files - a standard TMY3 from NIWA in New Zealand from 2024, and a DSY file for overheating analyse…

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## [Need help accessing snow data EPW](https://discourse.ladybug.tools/t/need-help-accessing-snow-data-epw/35760)

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**Author:** [@taiyominami](https://discourse.ladybug.tools/u/taiyominami)\
**Replies:** 0\
**Last updated:** [February 2, 2025, 8:55pm UTC](https://discourse.ladybug.tools/t/need-help-accessing-snow-data-epw/35760 "2025-02-02T20:55:52Z")

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I’d like help accessing all of the weather data (but specifically snow-related data) that’s shown below in the Ladybug website. As of right now, the importEPW component has just a limited set of outputs that don’t includ…

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## [Combining two epw file](https://discourse.ladybug.tools/t/combining-two-epw-file/35743)

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**Author:** [@simamow](https://discourse.ladybug.tools/u/simamow)\
**Replies:** 1\
**Last updated:** [January 30, 2025, 9:33pm UTC](https://discourse.ladybug.tools/t/combining-two-epw-file/35743 "2025-01-30T21:33:25Z")

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For a city, I have four weather files for different time periods, with some overlap for certain years. The number of data points for a given year is not the same in each file. For example, one file has about 1400 data po…

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## ["Solution exception: name 'w' is not defined" Error](https://discourse.ladybug.tools/t/solution-exception-name-w-is-not-defined-error/35001)

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**Author:** [@Fikret](https://discourse.ladybug.tools/u/Fikret)\
**Replies:** 2\
**Last updated:** [October 29, 2024, 5:13pm UTC](https://discourse.ladybug.tools/t/solution-exception-name-w-is-not-defined-error/35001 "2024-10-29T17:13:32Z")

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Hi everyone, I hope you’re all doing well. I’m currently working with Ladybug and have encountered an issue. When I work on a file, everything runs smoothly, but as soon as I try to copy the file, I receive the followin…

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## [Weather data for any location](https://discourse.ladybug.tools/t/weather-data-for-any-location/11412)

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**Author:** [@Lukas](https://discourse.ladybug.tools/u/Lukas)\
**Replies:** 11\
**Last updated:** [October 11, 2024, 2:14pm UTC](https://discourse.ladybug.tools/t/weather-data-for-any-location/11412 "2024-10-11T14:14:36Z")

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Access hourly weatherdata for any location from here https://rokka.shinyapps.io/shinyweatherdata Now updated with ERA5 global reanalysis climate data from Copernicus/ECMWF. Global coverage and data from 1980 until recen…

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## [1. Solution exception:Cannot find an epw file at LOCATION,](https://discourse.ladybug.tools/t/1-solution-exception-cannot-find-an-epw-file-at-location/34575)

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**Author:** [@MCBMCB](https://discourse.ladybug.tools/u/MCBMCB)\
**Replies:** 1\
**Last updated:** [September 17, 2024, 7:14pm UTC](https://discourse.ladybug.tools/t/1-solution-exception-cannot-find-an-epw-file-at-location/34575 "2024-09-17T19:14:33Z")

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Hello, what can cause this problem? Is it because of a “corrupt” file? I got it from here, which looks legit: \\climatewebsite\\WMO\_Region\_6\_Europe\\DEU\_Germany Is there any way to check or load the file anyways? Thanks …

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## [Problem about .epw file outputs and Data Collection](https://discourse.ladybug.tools/t/problem-about-epw-file-outputs-and-data-collection/34173)

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**Author:** [@dmaraujo](https://discourse.ladybug.tools/u/dmaraujo)\
**Replies:** 6\
**Last updated:** [August 26, 2024, 2:24pm UTC](https://discourse.ladybug.tools/t/problem-about-epw-file-outputs-and-data-collection/34173 "2024-08-26T14:24:39Z")

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Hi everyone! I’m having a trouble while connecting my .epw file especially to the outdoor comfort component. It says: “1. Solution exception:input key:location/dataType/units/frequency/startsAt/endsAt is not valid. Expe…

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## [How to create an EPW file](https://discourse.ladybug.tools/t/how-to-create-an-epw-file/33815)

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**Author:** [@deborax](https://discourse.ladybug.tools/u/deborax)\
**Replies:** 3\
**Last updated:** [August 5, 2024, 9:55am UTC](https://discourse.ladybug.tools/t/how-to-create-an-epw-file/33815 "2024-08-05T09:55:37Z")

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Hi everyone, I need to create an EPW file from bioclimatic data that I will collect myself using sensors (is that practicable?), because this data set should reflect the microclimate around a specific building and be up…

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## [Wich formula is used for the global\_horizontal\_rad in the CreateEPW comp?](https://discourse.ladybug.tools/t/wich-formula-is-used-for-the-global-horizontal-rad-in-the-createepw-comp/31100)

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**Author:** [@LaFleur](https://discourse.ladybug.tools/u/LaFleur)\
**Replies:** 0\
**Last updated:** [July 30, 2024, 10:29am UTC](https://discourse.ladybug.tools/t/wich-formula-is-used-for-the-global-horizontal-rad-in-the-createepw-comp/31100 "2024-07-30T10:29:02Z")

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Dear , I have a curiosity about the creation of a EPW-File. By creating an EPW file through the \_CreateEPW component, even if I don’t enter any information regarding the direct solar radiation and any “sun elevation” t…

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## [New current and future climate files](https://discourse.ladybug.tools/t/new-current-and-future-climate-files/24728)

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**Author:** [@ergopikas](https://discourse.ladybug.tools/u/ergopikas)\
**Replies:** 2\
**Last updated:** [April 22, 2024, 10:05am UTC](https://discourse.ladybug.tools/t/new-current-and-future-climate-files/24728 "2024-04-22T10:05:51Z")

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Hi In Estonia, new .epw files have been created for current and future climate. We have been using these in the IDA-ICE without any major problems. However, we are struggeling to undestand why these files are not worki…

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## [Climate One Building Weather Files Updated Through 2021](https://discourse.ladybug.tools/t/climate-one-building-weather-files-updated-through-2021/17996)

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**Author:** [@josephyang](https://discourse.ladybug.tools/u/josephyang)\
**Replies:** 9\
**Last updated:** [March 19, 2024, 11:41pm UTC](https://discourse.ladybug.tools/t/climate-one-building-weather-files-updated-through-2021/17996 "2024-03-19T23:41:46Z")

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I don’t think Dru and Linda have accounts here so thought it would be good to share. (from Dru’s LinkedIn Post) Updated Global Simulation Climate Data Set Available from Climate.OneBuilding.Org In April 2022, Climat…

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## [EPW period error](https://discourse.ladybug.tools/t/epw-period-error/16054)

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**Author:** [@seghier](https://discourse.ladybug.tools/u/seghier)\
**Replies:** 2\
**Last updated:** [October 1, 2021, 12:41am UTC](https://discourse.ladybug.tools/t/epw-period-error/16054 "2021-10-01T00:41:34Z")

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Hello I choose a period in this example from 02 Jan 08:00 to 02 Jan 12:00 where wind speed list is: 0,0,1,0,1.5 , but using the output period with import epw give different wind speed from 7:00h to 11:00h How to fix t…

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## [LB Import EPW 1.7.0 error: reported data at a certain index doesn't match with the original epw file](https://discourse.ladybug.tools/t/lb-import-epw-1-7-0-error-reported-data-at-a-certain-index-doesnt-match-with-the-original-epw-file/23277)

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**Author:** [@MatteoFBC](https://discourse.ladybug.tools/u/MatteoFBC)\
**Replies:** 1\
**Last updated:** [November 20, 2023, 4:09pm UTC](https://discourse.ladybug.tools/t/lb-import-epw-1-7-0-error-reported-data-at-a-certain-index-doesnt-match-with-the-original-epw-file/23277 "2023-11-20T16:09:32Z")

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Hi @chris @mostapha and Ladybug Team, we might have spotted an error in the actual component Import EPW. Index 0 seems to report the last value of the epw original file for a first group of factors (which includes Tair, …

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## [Discrepancy in weather files](https://discourse.ladybug.tools/t/discrepancy-in-weather-files/22501)

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**Author:** [@srjn31](https://discourse.ladybug.tools/u/srjn31)\
**Replies:** 0\
**Last updated:** [August 24, 2023, 11:58pm UTC](https://discourse.ladybug.tools/t/discrepancy-in-weather-files/22501 "2023-08-24T23:58:42Z")

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I was testing some radiation studies and found this discrepancy between different weather files. It only occurs for some very specific dates - 22 Dec being one of them Please refer to the image of sky domes below - …

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## [CSWD files from OneBuilding have serious data quality issues - psych charts, wind speed and cloud cover](https://discourse.ladybug.tools/t/cswd-files-from-onebuilding-have-serious-data-quality-issues-psych-charts-wind-speed-and-cloud-cover/12314)

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**Author:** [@LelandCurtis](https://discourse.ladybug.tools/u/LelandCurtis)\
**Replies:** 6\
**Last updated:** [August 3, 2023, 1:22pm UTC](https://discourse.ladybug.tools/t/cswd-files-from-onebuilding-have-serious-data-quality-issues-psych-charts-wind-speed-and-cloud-cover/12314 "2023-08-03T13:22:56Z")

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I’m simulating Chinese CSWD weather files and running into issues with the psych chart, cloud cover, and wind roses. These errors appear only in the CSWD files from OneBuilding. DOE files appear fine. I’m sharing my expl…

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## [Building your own EPW file](https://discourse.ladybug.tools/t/building-your-own-epw-file/1954)

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**Author:** [@PetrVacek](https://discourse.ladybug.tools/u/PetrVacek)\
**Replies:** 29\
**Last updated:** [August 1, 2023, 6:10pm UTC](https://discourse.ladybug.tools/t/building-your-own-epw-file/1954 "2023-08-01T18:10:42Z")

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I need to evaluate some historical weather data of a little village at Haiti. The only format I can get is XML, JSON or HTML. Is there a way how to feed that data to Ladybug and use it’s tools to evaluate it? For now I …

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## [Does EPW file take daylight savings time into consideration?](https://discourse.ladybug.tools/t/does-epw-file-take-daylight-savings-time-into-consideration/1928)

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**Author:** [@Ibby](https://discourse.ladybug.tools/u/Ibby)\
**Replies:** 5\
**Last updated:** [November 15, 2022, 8:25pm UTC](https://discourse.ladybug.tools/t/does-epw-file-take-daylight-savings-time-into-consideration/1928 "2022-11-15T20:25:52Z")

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## [Ladybug - how can I extract one year of data from an EPW for Analysis?](https://discourse.ladybug.tools/t/ladybug-how-can-i-extract-one-year-of-data-from-an-epw-for-analysis/20007)

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**Author:** [@Anu](https://discourse.ladybug.tools/u/Anu)\
**Replies:** 0\
**Last updated:** [November 10, 2022, 5:01am UTC](https://discourse.ladybug.tools/t/ladybug-how-can-i-extract-one-year-of-data-from-an-epw-for-analysis/20007 "2022-11-10T05:01:32Z")

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So I realize that when you download an EPW from online, it often has data across multiple different years. For example, this Newark EPW file has 10 non—consecutive years of data between (1976 -2003). I feel like this is…

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## [EPW / Weather data adjustment](https://discourse.ladybug.tools/t/epw-weather-data-adjustment/2562)

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**Author:** [@JouriKanters](https://discourse.ladybug.tools/u/JouriKanters)\
**Replies:** 11\
**Last updated:** [September 1, 2022, 4:01pm UTC](https://discourse.ladybug.tools/t/epw-weather-data-adjustment/2562 "2022-09-01T16:01:24Z")

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Hi all, I want my students to understand energy simulations better. So we are comparing a simple Excel sheet with the results of E+ / HB simulations. I want to make two additional weather files from existing weather fi…

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## [TMY/TMYx EPW weather data with high East-West deviation using GenCumulativeSky.exe](https://discourse.ladybug.tools/t/tmy-tmyx-epw-weather-data-with-high-east-west-deviation-using-gencumulativesky-exe/19041)

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**Author:** [@vhoang](https://discourse.ladybug.tools/u/vhoang)\
**Replies:** 2\
**Last updated:** [July 28, 2022, 1:48pm UTC](https://discourse.ladybug.tools/t/tmy-tmyx-epw-weather-data-with-high-east-west-deviation-using-gencumulativesky-exe/19041 "2022-07-28T13:48:23Z")

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Hi everyone, We have an issue with the Honeybee\_Generate Cumulative Sky component using different TMY-Datasets. We tried with 2 different sources of EPW files, including PV-GIS and climate.onebuilding.org and both resu…

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## [Bug in Create EPW component](https://discourse.ladybug.tools/t/bug-in-create-epw-component/17675)

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**Author:** [@VincentLugherini](https://discourse.ladybug.tools/u/VincentLugherini)\
**Replies:** 4\
**Last updated:** [March 14, 2022, 2:20pm UTC](https://discourse.ladybug.tools/t/bug-in-create-epw-component/17675 "2022-03-14T14:20:06Z")

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Hi @chris It seems there is a bug in the dragonfly component “create EPW”. The created EPW have global horizontal radiation values looking like illuminance values in lux : It seems to be because of this line in the …

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## [Importing future weather files in LBT1.3](https://discourse.ladybug.tools/t/importing-future-weather-files-in-lbt1-3/16845)

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**Author:** [@suryakiran](https://discourse.ladybug.tools/u/suryakiran)\
**Replies:** 1\
**Last updated:** [December 10, 2021, 6:38pm UTC](https://discourse.ladybug.tools/t/importing-future-weather-files-in-lbt1-3/16845 "2021-12-10T18:38:45Z")

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I’m trying to use future EPW files generated using EPWShiftR in LBT v1.3. I am getting this error when importing the EPW file. Solution exception:invalid literal for float(): CCWeatherGen EPW Analysis\_Philadelphia\_LBT…

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## [Using Dragon Fly to make an EPW File - Tutorial somewhere?](https://discourse.ladybug.tools/t/using-dragon-fly-to-make-an-epw-file-tutorial-somewhere/13110)

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**Author:** [@remymerm](https://discourse.ladybug.tools/u/remymerm)\
**Replies:** 4\
**Last updated:** [December 2, 2021, 1:15pm UTC](https://discourse.ladybug.tools/t/using-dragon-fly-to-make-an-epw-file-tutorial-somewhere/13110 "2021-12-02T13:15:08Z")

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Hi, I am looking to make an EPW file from 1 year of observations I have from my own wx station, they are in a csv…hourly obs. Wondering if there is a tutorial or directions somewhere for how to get started to build it c…

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## [Mars Base Rhino](https://discourse.ladybug.tools/t/mars-base-rhino/16711)

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**Author:** [@Alakelele](https://discourse.ladybug.tools/u/Alakelele)\
**Replies:** 0\
**Last updated:** [November 28, 2021, 11:07pm UTC](https://discourse.ladybug.tools/t/mars-base-rhino/16711 "2021-11-28T23:07:09Z")

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Hello Forum On the 28th of October 2021, I presented at the International Astronautical Conference 2021 in DUBAI my most recent project IAC-21-B3.7.10 “Using Computational Techniques for the Optimal Design of Evolving H…

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## [CBE Clima Tool :: On-line Climate Analysis](https://discourse.ladybug.tools/t/cbe-clima-tool-on-line-climate-analysis/15695)

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**Author:** [@gbetti](https://discourse.ladybug.tools/u/gbetti)\
**Replies:** 2\
**Last updated:** [October 11, 2021, 8:43pm UTC](https://discourse.ladybug.tools/t/cbe-clima-tool-on-line-climate-analysis/15695 "2021-10-11T20:43:12Z")

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Dear Ladybug Tools users, One of the great features of this community and the environmental design at large is the wealth of high-quality open-source projects that have been developed over time -Ladybug, but also Radian…

[Next page](https://discourse.ladybug.tools/tag/epw/2.md?match_all_tags=true&page=1&tags%5B%5D=epw)