Analysis of component and total heating, cooling, and lighting energy consumption attributable to skylights in commercial buildings, as well as peak demand impacts. Also provides hourly and monthly patterns of illumination levels from daylighting. The American Architectural Manufacturers Association's AAMASKY (AAMA SKYlight) consists of a Skylight Design Guidelines Handbook containing worksheet-based calculations, as well as a software spreadsheet that allows much more rapid determination of skylight impacts; all required data for analysis in ten U.S. climates is provided. Directly applicable to simple diffusing skylight designs for most types of commercial buildings. Helps achieve compliance with performance-based building codes. With experience, can be used for some types of sloped glazing and atrium designs.