scope:

ABSTRACT

Energy use for heating, ventilation and air conditioning (HVAC) is one of the largest end-use categories in the buildings sector. Thus far, energy codes and standards in the United States have focused on equipment- and component-level prescriptive efficiency requirements but do not recommend any particular system type over another. Energy codes and standards also have performance compliance paths, but these are implemented at the whole-building level and allow trade-offs with other end-use categories.

Building energy codes and standards are now implementing or considering HVAC system-level energy performance metrics in order to move beyond or supplement component-level efficiency requirements. These new end-use category performance metrics have the potential to provide a new performance path for achieving HVAC energy savings while providing maximum design flexibility.

The DOE Commercial Prototype Building Models are being used to develop potential system-level requirements for energy codes and standards, therefore it makes sense to examine them in detail. This paper explores how the HVAC end-use category has evolved over different energy code vintages and provides insights regarding different building types and climate zone locations. This paper presents the changes in whole-category HVAC energy performance for the prototype building models for ASHRAE Standard 90.1 versions 2004 through 2019 as well as the IECC models for 2006 through 2018.