Although they've been around for at least three decades, only in the last few years have metal halide lamps come to be specified routinely in such applications as arena and stadium lighting, parking lots, and schools.
Because of the way they are engineered, metal halide lamps provide energy savings and bright white light with a quicker hot re-start than fluorescent or incandescent lamps.
"Metal halide lamps are used in any application where energy savings is a priority," says Donna Bard, product manager at Solon, Ohio-based Venture Lighting, which produces up to 80% of such lamps in the U.S. Says Bard, "With the energy crisis out in California, we've seen a tremendous rise in [these] lamps."
According to Venture Lighting, whose products include a Pulse Start metal halide lamp, it would take five 100-watt incandescent lamps to produce the 9,000 lumens of light that a single 100-watt metal halide lamp can produce. In addition, metal halide lamps last an average 15,000 hours, about 15-20 times longer than incandescent lamps.
The metal halide lamp is powered by an igniter, not an internal starter in the circuitry, as in other lamps. The igniter enables two electrodes to create an arch in the tube chamber, creating white light. The lamp is then sustained by a connecting ballast.
Venture Lighting estimates that converting to metal halide lighting could save up to 10% of the total energy consumed in the U.S., resulting in a potential savings of $16 billion a year.
To light a typical 10,000 sq. ft. facility for 2,500 hours a year with incandescent lighting requires nearly four times more fuel than a similar facility equipped with metal halide lighting.