EnergyPlus Licensing

This document describes the licensing framework for EnergyPlus™ versions starting at 7.0. The licenses are intended to encourage the use, improvement and widespread adoption of EnergyPlus. The version 7.0 licensing scheme differs from the one use for versions 1.0 through 6.x in three major ways:

  • No fee executable distribution license. There are no fees for use or distribution of EnergyPlus in executable form. You may use the EnergyPlus executable (either the standalone application or the library), combine it with other programs, and redistribute it (as either a desktop application or a web application), for any purpose (commercial or otherwise) free of charge. Use of this license requires that You refer to the specific EnergyPlus version as "EnergyPlus vX."

  • Open source license. For the first time, EnergyPlus is available under a true open-source license. Under this license, which is modeled after the Mozilla Public License (MPL), you may obtain EnergyPlus source code, modify it, combine it with other software that is licensed under different terms, distribute it, and re-license it. The license is "weak copyleft" in that it covers only EnergyPlus and its modifications going forward. Code that is combined with EnergyPlus is not affected. This license requires that you distribute the source code for EnergyPlus modifications and that you refer to the EnergyPlus component of your distribution as "a modified version of EnergyPlus vX." You may remove the "modified" designation by obtaining prior written permission from Berkeley Lab. As with any open source license, there is no fee.

  • Less restrictive commercial source license. The revised commercial source-distribution license has been relaxed to permit sub-licensing of proprietary modifications to EnergyPlus. Under this license, you may obtain EnergyPlus source code, modify it, combine it with other software that is licensed under different terms, distribute it, and re-license it. Unlike the open-source license, you are not required to make your modified EnergyPlus source code available; you retain exclusive control over these modifications. You are still required to refer to your copy of EnergyPlus as "modified." In the new licensing framework, this is the only license that requires a fee: $10,000 US for the first licensed version and $3,000 for major version updates. Very few scenarios should require this license; the open source license should suit most purposes. The fee attached to this license is intended to encourage use of the open source license, while providing additional rights in cases where they may be needed.

Bug fixes, maintenance releases, and minor version releases of EnergyPlus will be made available to existing EnergyPlus licensees at no additional charge on an "if and when available" basis. Future major version releases of EnergyPlus may be made available either at no additional charge or for a separate license fee. The licensing scheme and fee schedule is subject to change for future versions. If you have questions, please send a message to Here is the current fee schedule:

Executable End-Use License Agreement $0  
Executable Distribution License Agreement $0 Read the indicated license carefully and follow the instructions on the final page to officially obtain the license and download the appropriate files.
Open Source License Agreement $0
Commercial Source License Agreement $10,000/$3,000

Using the EnergyPlus Name

The above licenses require that you refer to the EnergyPlus component of a larger work as either "EnergyPlus vX" or "a modified version of EnergyPlus vX" as appropriate. If you would like to use the name EnergyPlus, Energy+, E+, e+, or any similarly confusing moniker to name, market, or promote the larger work, you must obtain prior written permission from Berkeley Lab.

Distributing Weather Files

While the above licenses allow you to distribute EnergyPlus and combined and derivative works incorporating EnergyPlus, note that redistributing weather files such as International Weather for Energy Calculations (IWEC) requires obtaining a separate license directly from the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). You may also want to read the ASHRAE IWEC files use restrictions. The ISHRAE and RMY files have similar restrictions. For details, contact EnergyPlus support.

Beta License Agreement

Prior to general availability release of a new version of EnergyPlus, EnergyPlus may, from time to time, be made available for beta testing under a Beta License Agreement. The Beta License Agreement grants you the right to use the EnergyPlus beta executable for test and evaluation purposes only until such beta version is superseded by a newer beta version or a production release.

  • The Beta License Agreement allows non-exclusive use for test and evaluation purposes only within your company at any site by any number of users.
  • You may not distribute the EnergyPlus beta outside of your company or institution.

Contributing to EnergyPlus

EnergyPlus is an open-source project and the EnergyPlus team accepts contributions to EnergyPlus source, utilities, test files, documentation, and other materials distributed with the program. Visit the contribution page to learn more.