Atlanta -- The requirements of the 2013 revision of an energy standard recently published by ASHRAE and IES will result in buildings that could achieve 6% to 8% more efficiency than buildings built to the 2010 standard.
Published in October 2013, ANSI/ASHRAE/IES Standard 90.1-2013, Energy Standard for Buildings Except Low-Rise Residential Buildings, provides minimum requirements for the energy-efficient design of buildings except low-rise residential buildings.
Pacific Northwest National Laboratories (PNNL), in support of the Department of Energy’s Building Energy Codes Program, conducted the energy savings analysis on 110 addenda included in the standard.
PNNL’s analysis shows that the site and energy cost savings are 37.7% and 37.8%, respectively, by using the 2004 standard as baseline for the regulated loads only. For the whole building energy consumptions, national aggregated site energy savings are 29.5% and energy cost savings are 29.0%.
On a nationally aggregated level, building-type energy savings range from 19.3% to 51.9% and energy-cost savings from 18.6% to 50.6%. These figures include energy use and cost from the whole building energy consumptions including plug and process loads.
The energy reduction was achieved through 33 addenda related to major changes to requirements regarding building envelope, lighting, mechanical and the energy cost budget. The most significant changes are:
Building Envelope. Opaque elements and fenestration requirements have been revised to increase stringency while maintaining a reasonable level of cost-effectiveness.
Lighting: These changes include improvements to daylighting and daylighting controls, space-by-space lighting power density limits, thresholds for toplighting and revised controls requirements and format.
Mechanical: Equipment efficiencies are increased for heat pumps, packaged terminal air conditioners, single package vertical heat pumps, air conditioners and evaporative condensers. Also, fan efficiency requirements are introduced for the first time.
Additional provisions address commercial refrigeration equipment, improved controls on heat rejection and boiler equipment, requirements for expanded use of energy recovery, small motor efficiencies and fan power control and credits. Control revision requirements have been added to the standard such as direct digital controls in many applications.