EPW File Extension

EPW file icon
EnergyPlus Weather Data Format
  • Developer
    U.S. Department of Energy
  • Category
  • Popularity
    2.8 (16 votes)

What is EPW file?

Full format name of files that use EPW extension is EnergyPlus Weather Data Format. EnergyPlus Weather Data Format specification was created by U.S. Department of Energy. Files with EPW extension may be used by programs distributed for Windows platform. Files with EPW extension are categorized as Data Files files. The Data Files subset comprises 1326 various file formats. Users are advised to use Ecotect Analysis software for managing EPW files, although 1 other programs can also handle this type of file.

Programs which support EPW file extension

Below is a table that list programs that support EPW files. EPW files can be encountered on all system platforms, including mobile, yet there is no guarantee each will properly support such files.

Programs that support EPW file

How to open file with EPW extension?

Problems with accessing EPW may be due to various reasons. Fortunately, most common problems with EPW files can be solved without in-depth IT knowledge, and most importantly, in a matter of minutes. The following is a list of guidelines that will help you identify and solve file-related problems.

Step 1. Get the Ecotect Analysis

Install software to open EPW file Problems with opening and working with EPW files are most probably having to do with no proper software compatible with EPW files being present on your machine. This one is an easy one. Select Ecotect Analysis or one of the recommended programs (for example, EnergyPlus) and download it from appropriate source and install on your system. On the top of the page a list that contains all programs grouped based on operating systems supported can be found. If you want to download Ecotect Analysis installer in the most secured manner, we suggest you visit website and download from their official repositories.

Step 2. Update Ecotect Analysis to the latest version

Update software that support file extension EPWIf you already have Ecotect Analysis installed on your systems and EPW files are still not opened properly, check if you have the latest version of the software. Software developers may implement support for more modern file formats in updated versions of their products. The reason that Ecotect Analysis cannot handle files with EPW may be that the software is outdated. All of the file formats that were handled just fine by the previous versions of given program should be also possible to open using Ecotect Analysis.

Step 3. Associate EnergyPlus Weather Data Format files with Ecotect Analysis

After installing Ecotect Analysis (the most recent version) make sure that it is set as the default application to open EPW files. The process of associating file formats with default application may differ in details depending on platform, but the basic procedure is very similar.

Associate software with EPW file on Windows

Change the default application in Windows

  • Choose the Open with entry from the file menu accessed by right-mouse clicking on the EPW file
  • Next, select the Choose another app option and then using More apps open the list of available applications
  • To finalize the process, select Look for another app on this PC entry and using the file explorer select the Ecotect Analysis installation folder. Confirm by checking Always use this app to open EPW files box and clicking OK button.
Associate software with EPW file on Mac

Change the default application in Mac OS

  • From the drop-down menu, accessed by clicking the file with EPW extension, select Information
  • Find the Open with option – click the title if its hidden
  • From the list choose the appropriate program and confirm by clicking Change for all....
  • A message window should appear informing that This change will be applied to all files with EPW extension. By clicking Continue you confirm your selection.

Step 4. Check the EPW for errors

Should the problem still occur after following steps 1-3, check if the EPW file is valid. Problems with opening the file may arise due to various reasons.

Check EPW file for viruses
1. The EPW may be infected with malware – make sure to scan it with an antivirus tool.

If the EPW is indeed infected, it is possible that the malware is blocking it from opening. Immediately scan the file using an antivirus tool or scan the whole system to ensure the whole system is safe. If the EPW file is indeed infected follow the instructions below.

2. Check whether the file is corrupted or damaged

If you obtained the problematic EPW file from a third party, ask them to supply you with another copy. It is possible that the file has not been properly copied to a data storage and is incomplete and therefore cannot be opened. When downloading the file with EPW extension from the internet an error may occurred resulting in incomplete file. Try downloading the file again.

3. Verify whether your account has administrative rights

Sometimes in order to access files user need to have administrative privileges. Log out of your current account and log in to an account with sufficient access privileges. Then open the EnergyPlus Weather Data Format file.

4. Check whether your system can handle Ecotect Analysis

If the systems has insufficient resources to open EPW files, try closing all currently running applications and try again.

5. Check if you have the latest updates to the operating system and drivers

Up-to-date system and drivers not only makes your computer more secure, but also may solve problems with EnergyPlus Weather Data Format file. It may be the case that the EPW files work properly with updated software that addresses some system bugs.

Do you want to help?

If you have additional information about the EPW file, we will be grateful if you share it with our users. To do this, use the form here and send us your information on EPW file.

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