1.1 Overview of SPOT

SPOT consists of a series of screens that the user navigates sequentially, as illustrated in Figure 1-1 that shows a flow diagram for the program. The sequence of the user input and performance reporting screens is designed to minimize user wait time, by running required calculations behind the scenes before they are needed. This sequential staging of the interface screens also provides a coherent structure to the process of designing a daylighting, electric lighting and photosensor control system. This results in two main functions of the program: Daylighting Design Tools and Photosensor Analysis Tools.

The Daylighting Design Tools consist of all the geometric, material, and site and usage inputs, and simulates the electric lighting performance, design day and annual daylighting performance, and a variety of standard daylighting performance metric reports, including standard LEED and CHPS reports. The final stage of the Design Tool provides recommended photosensor placement for the analyzed space. These recommended placements provide good base recommendations however further optimization can be attained in the Analysis Tool section.

The Photosensor Analysis Tools consists of two screens, EnergyPlus and DOE-2 schedule generators, and Commissioning reports. The first screen allows the user to mix and match photocell placement and controller settings with the defined luminaire zones, and analyze the resulting correlations and estimated annual performance. The second screen takes the set photosensor scenarios, analyzes their performance throughout the year using annual hour-by-hour weather data, and provides a variety of annual results allowing for an in-depth review of the system from both a qualitative (light levels) and quantitative (energy savings) standpoint. From here you can export both DOE-2 (Equest) and EnergyPlus schedule files that represent the lighting controls throughout the year for that space. There are also commissioning reports available that provide a printable version of the photocell placement and photosensor controller commissioning settings as they relate to the specific product selected.