The use of DOE-2 to determine the relative energy performance of daylighted retail stores covered with tension supported fabric roofs

With increasing interest amongst the architectural and engineering community in daylighted buildings, there is a need to evaluate the relative energy performance of those buildings. One means of daylighting a building is to use a coated glass fiber fabric roof. With such a roof, it has been found that sufficient daylight is admitted to allow most artificial lighting to be turned off during the daytime hours. However, solar cooling loads and conductive loads may be greater than for conventionally roofed commercial buildings. With the fabric roofed buildings capable of using considerably less energy for artificial lighting, yet possibly requiring greater use of energy for space heating and cooling, the relative energy performance is a matter of trade-offs.To determine this relative energy performance of fabric roofed and conventionally roofed retail stores, a modified version of DOE-2.1A was used with weather data from 19 cities located within the United States. In the analyses, both single-layer and double-layer roofs were studied as were stores with different levels of electric power for artificial lighting. In general, the results suggest that a fabric roofed store will use less total energy than a conventional roofed store in a geographic area with a mild climate but that it will use more energy in a cold climate area.