Energy Savings Resulting from Shading Devices on Single-Family Residences in Austin, Texas

Abstract

Potential annual energy savings resulting from window shading devices on three prototypical Austin, Texas, single-family residences were computed in this study. Savings were calculated for interior (shades, blinds, draperies, window film, and tinted windows) and exterior (solar screens, awnings, overhangs, and the effects of recessed windows and vegetation) shading devices. The analysis was conducted with the DOE-2 building energy analysis computer program. Nominal baseline cases (single glazing, gas heating, and nominal shading from eaves and neighboring buildings) were run for each prototype. Selected baseline variants (double glazing, all electric, and no eaves or neighbor shading) were run to test parameter sensitivity. Results are reported in terms of the annual heating and cooling energy use and energy cost, with each device in place, as compared to the baseline cases. The devices are ranked in term of energy savings and energy coat savings. Another significant result is the multiple-regression correlation of annual heating and cooling energy savings with Shading Coefficient and U-value that generalizes the performance of the shading devices.