by Ann Withanee — November 4, 2011—Building owners and facilities executives employ various strategies to cut back electricity, sometimes without specific goals. They now have a standard to judge how effective their solutions are with the issuance of ASHRAE’s 2010 energy standard for state buildings. Further, the U.S. Department of Energy (DOE) has issued a ruling that establishes the 2010 standard as the commercial building reference standard for state building energy codes. The 2010 standard supersedes Standard 90.1-2007.
Since being developed in response to the energy crisis in the 1970s, Standard 90.1 now influences building designs worldwide. It has become the basis for building codes, and the standard for building design and construction throughout the United States. ASHRAE and IES publish a revised version of the standard every three years.
In an announcement in the October 19 edition of The Federal Register, DOE attributes greater energy savings to improvements in ANSI/ASHRAE/IESNA Standard 90.1-2010, Energy Standard for Buildings Except Low-Rise Residential Buildings, than to the 2007 edition. “The DOE has determined that the quantitative analysis of the energy consumption of buildings built to Standard 90.1-2010, as compared to buildings built to Standard 90.1-2007, indicates national source energy savings of approximately 18.2 percent of commercial building consumption.” Additionally, DOE has determined site energy savings are estimated to be approximately 18.5 percent. The savings are related to better lighting, daylighting, controls, building envelope and mechanical systems, and application to more systems.
With the October 19 ruling, Standard 90.1-2010 serves as the commercial building reference standard for state building energy codes under the federal Energy Conservation and Production Act. As a result, states have a deadline of October 18, 2013 to certify that they have updated the provisions of their commercial building code regarding energy efficiency to meet or exceed 90.1-2010.
The DOE noted that the newer version of the standard contains 19 positive impacts on energy efficiency. These impacts include changes made through the public review process in which users of the standard can comment and offer guidance on proposed requirements. Specifically the positive impacts include:
- Requirements for daylighting controls under skylights and commissioning of daylighting controls
- Increased use of heat recovery
- Cool roofs in hot climates
- Lower illuminance in certain exterior zones
- Skylights and daylighting in some building types
- Reduced ventilation energy
- Supply air temperature reset for non-peak conditions
- Efficiency requirements for data centers
- Lower lighting power densities
- Control of exterior lighting
- Occupancy sensor for many specific applications
- Daylighting control requirements for side-lighted spaces
- Daylighting controls in more spaces
- Updated chiller efficiency requirements
- Extension of VAV fan control requirements
- Expansion of new lighting power densities to more retrofits and automatic damper requirements and use of economizers
- Minimization of exceptions to switched receptacle requirement
