Where color is not important, this light is a good choice because it renders all colors as tones of yellow or gray. Security lighting often uses this type of lighting. Can Save Money Lighting controls are simply devices for turning lights on and off or for dimming them. The various types include a standard snap switch, photocells, timers, occupancy sensors, and dimmers. Three-way snap switches make it easier to turn off lights in unused areas.
Photocells respond to natural light levels.
For example, photocells switch outdoor lights on at dusk and off at dawn. Some advanced designs gradually raise and lower fluorescent light levels with changing daylight levels. Mechanical or electronic timers automatically turn on and off indoor or outdoor lights. Occupancy sensors activate lights when a person is in the area and then turn off the lights after the person has left. Dimmers reduce the wattage and output of incandescent and fluorescent lamps but will save energy only when used consistently.