Higher energy performance has evolved from an aspiration to an expectation. Owners of buildings—especially those certified under rating systems like LEED—increasingly count on an energy savings payback. And a wave of “net zero energy” buildings promises to generate enough energy on-site from renewable sources to equal or exceed demand. As a result, predictive energy models face new scrutiny. “In the last five years, energy modelers have learned that they will have to answer for their models,” says Laurie Canup, an associate with Portland, Oregon–based THA Architecture.
Energy modeling depends on physics-based simulation to predict how energy will flow through a building, taking account of mechanical systems, materials, control schemes, occupants, and weather. The software packages were created to help architects and engineers choose among competing design options, and they do that well. As Matthew Herman, an energy-modeling expert with engineering firm Buro Happold puts it: “The models are more than accurate enough to consistently drive design teams toward the right decision.”