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Recessed downlights are the most commonly installed type of lighting fixture in residential new construction. New developments in LED technology and luminaire design may enable significant energy savings in this application. This fact sheet compares the energy and lighting performance of downlights using different light sources. Although originally intended for directional lighting, recessed downlights are now used widely for general ambient lighting in kitchens, hallways, bathrooms, and other areas of the home. Other types of downlights using spot lamps, reflectors, and lenses are also used for art, accent, display, and wall lighting. In some applications, like media rooms and dining areas, downlights are operated on dimming circuits. The most common light source used in residential downlights is a 65-watt incandescent reflector-style lamp with a standard Edison base. Other commonly used options include A-type incandescent lamps, and PL-type, spiral, or reflector CFLs. The light output of a traditional recessed downlight is a function of the lumens produced by the lamp and the luminaire (fixture) efficiency. Reflector-style lamps are specially shaped and coated to emit light in a defined cone, while “A” style incandescent lamps and CFLs emit light in all directions, leading to significant light loss unless the luminaire is designed with internal reflectors. Downlights using non-reflector lamps are typically only 50% to 60% efficient, meaning about half the light produced by the lamp is wasted inside the fixture. Recently, LED downlights have come on the market. Recently, LED downlights have come on the market. Below are examples of performance data for residential recessed downlight using several different light sources, including two LED products. These data should not be used to generalize the performance of fixture types, but are provided as examples. Examples of Recessed Downlight Performance Using Different Light Sources
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Incandescent |
Fluorescent |
Fluorescent |
LED |
LED |
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65W BR-30 Flood |
13W 4-pin
Spiral CFL |
15W R-30 CFL |
LED 1 |
LED 2 |
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Rated lamp lumens |
725 |
860 |
750 |
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Lamp wattage (nominal W) |
65 |
13 |
15 |
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Delivered light output (lumens), initial |
652 |
514 |
675 |
300 |
730 |
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Luminaire wattage (nominal W) |
65 |
12 |
15 |
15 |
12 |
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Luminaire efficacy (lm/W) |
10 |
42 |
45 |
20 |
60 |
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