Nomographs for Predesign Analysis of the Potential Electrical Eenrgy and Load Savings from Daylighting

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The nomographs presented here are intended to assist designers in making initial decisions concerning daylightings potential as a strategy for energy conservation and load management in commercial buildings. Once the basic operation of the nomographs is understood, they can be used to evaluate a design quickly. Each is intended to facilitate rapid comparison of alternative designs. Note that the thermal benefits and costs of windows or skylights and the heating/cooling impact of daylighting are not considered here.

These nomographs can be used to determine the potential daylighting benefits and costs, and thus the importance that should be assigned to further investigations of daylighting strategies. A poor showing would indicate that daylighting probably will not be a significant energy conservation strategy; a large potential savings indicates that additional effort should be expended to better define the impact of daylighting on all building systems.

The nomographs provide answers that suggest general design directions for cost-effective, daylighted buildings. They do not provide detailed design solutions. They offer a quick estimate of the magnitude of potential savings but do not provide the level of detail required to guarantee a workable solution.

Read through the entire package first and test the nomographs step by step to be sure you are using them properly. The small diagram on each nomograph indicates the direction of movement through that nomograph.

With a little practice, youll find the nomographs very simple and easy to use.

Again, the nomographs address annual electric lighting energy savings and peak load savings but exclude the thermal effects of fenestration systems.

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