Patent ID: 7781713

Claim:
A method for continuously calibrating a lighting system that facilitates daylight-harvesting, which involves combining the output of the lighting system with daylight and/or other light sources to reduce energy usage while providing lighting for an area, where the lighting system includes multi-level lighting capabilities for one or more light sources, the method comprising: determining a target light level for the area; performing the following operations: (a) measuring the light levels for the area when the lighting system is turned on at a high energy-level, is turned on at an intermediate energy-level, and is turned off; (b) determining from the measured light levels the light output of the lighting system for the different energy-levels; (c) measuring a present light level for the area; and (d) adjusting the light output of the lighting system based on the target light level, a lighting control parameter, the light output of the lighting system, and the present light level for the area; wherein determining a target light level for the area involves determining a minimum amount of light for the area based on the measured light levels output by the lighting system; repeating operations (a)-(d) during operation of the lighting system to ensure that the area receives the minimum amount of light over time without human intervention.