A Method of Optimizing Solar Control and Daylighting Performance in Commercial Office Buildings

We present a method for analyzing the annual cooling and lighting electricity use and peak demand associated with varying fenestration and lighting strategies in commercial office buildings. A prototypical office building module consisting of four perimeter zones and a central core zone was defined and a series of DOE-2 bidding energy simulations were completed to create a data base for varying fenestration and lighting system parameters. Using regression analysis procedures, we characterize electric energy and peak performance patterns as a function of solar aperture, defined as the product of shading coefficient and window-to-wall ratio, and efective daylighting aperture, defined as the product of visible transmittance and window-to-wall ratio. Optimum performance consists of defining the solar and effective daylighting aperture values that minimize annual energy consumption and peak demand, a process easily facilitated by the methods described herein.