Patent ID: 8666555

Claim:
A load control system for a building having a lighting load and a window located in a space of the building, the load control system comprising: a lighting control device for controlling a present intensity of the lighting load, the present intensity representative of the amount of power delivered to the lighting load; a motorized window treatment comprising a window treatment fabric for covering the window, the motorized window treatment operable to move the fabric between a fully-open position in which the window is not covered and a fully-closed position in which the window is covered; a daylight sensor for measuring an ambient light intensity in the space; and a controller operable to control the motorized window treatment to move the fabric to a position above the fully-closed position, the controller operable to control the lighting control device so as to adjust the present intensity of the lighting load in response to the ambient light intensity in the space as determined by the daylight sensor; wherein the controller is operable to determine the amount of power consumed by the lighting load based on the present intensity of the lighting load when the fabric of the motorized window treatment is at the position above the fully-closed position, and to determine if the lighting load is consuming less energy at the present intensity than the lighting load would consume if the fabric was at the fully-closed position, the motorized window treatment operable to move the fabric to the fully-closed position if the lighting load is not consuming less energy when the fabric is at the position above the fully-closed position.