On September 26, 2014 the U.S. Department of Energy issued a determination that ANSI/ASHRAE/IES Standard 90.1-2013 would achieve greater energy efficiency in buildings subject to the code than the 2010 version. The DOE analyses determined that the energy savings would be:
- 8.7% energy cost savings
- 8.5% source energy savings
- 7.6% site energy savings
As a result, all states are now required to certify that they have reviewed the provisions of their commercial building code regarding energy efficiency and, if necessary, updated their codes to meet or exceed the 2013 edition of Standard 90.1. States must submit certification of compliance by September 26, 2016 or explain why they cannot comply.
Why is this happening? The DOE is required by the Energy Conservation and Production Act (42 USC 6833) to review each new edition of ANSI/ASHRAE/IES Standard 90.1, and issue a determination as to whether the updated edition will improve energy efficiency in commercial buildings. If the determination is that the new version will improve energy efficiency, that standard becomes the new nationwide minimum requirement. States aren’t required to adopt Standard 90.1, but whatever standard they develop or adopt must be at least as stringent as Standard 90.1.
Some of the changes in the new standard are:
- Lumen Power Densities (LPDs) for most building and space types are reduced by approximately 10% from the 2010 version.
- More stringent requirements for lighting controls
- A new table format for determining LPDs and control requirements in individual spaces
The DOE website contains additional information, including PDFs of the analyses they conducted.