Agriculture Reference
In-Depth Information
Quartz halogen lamps produce incandescent light by heating tungsten filaments in a clear
quartz tube filled with halogen gas. Quartz lamps last up to four times longer than common
lightbulbs, cost more, burn brighter, and are 10 to 20 percent more efficient. They get very
hot and must be used in an enclosed fixture. The light from incandescent lamps has little
effect on the true color of objects. Quartz floodlights are a good choice for lighting barn
aisles, stalls, and pens.
Fluorescent lights are the coolest because instead of heating a filament, they use an elec-
tric arc to heat a small amount of mercury, which gives off UV radiation and causes phos-
phors on the inner surface of the lamp to glow. A 40-watt fluorescent bulb puts out twice
the light of a 95-watt incandescent tungsten bulb and uses less than half the electricity.
Fluorescent bulbs typically cost more but last ten times longer. The color of fluorescent
light varies significantly depending on the type of phosphors used in the lamp. They are
best used where they won't be turned off and on frequently and in a work area where you
might need concentrated lighting.
