High intensity discharge metal halide (MH) lamps came into vogue in the 1960’s. For fifty years, they reigned as the lighting option of choice for outdoor sports venues, airports, and other large spaces that required intense lighting for full evening operations. Since the early 2000’s, new LED lighting technology has supplanted MH lamps for at least nine reasons. In the battle of Metal Halide vs LED, here are some reasons why LED lighting beats metal halide.
Metal Halide vs LED Lighting
LEDs are far more efficient than MH lamps. The illumination of large spaces consumes significant amounts of electrical energy. LED lamps generate the same or better illumination as MHs with less than half the energy input. In many cases, the upfront cost of an LED lighting array will be recovered in under two years from energy cost savings alone.
LED fixtures are also far more durable and long-lasting than MH lamps. Many LED lamps with new heat sink technology will continue to provide at least 80% of their initial illumination levels after more than 50,000 hours, and in some cases more than 100,000 hours of operation. Over the same amount of time, MH lamps would need to be replaced at least five or six times. Accordingly, a location that switches to LED lamps will save substantial maintenance costs.
LEDs can provide better overall source and system efficiency than MH systems, with less LED light being lost within a fixture itself. Larger lighting fixtures tend to lose a substantial portion of the light output in the fixtures in which they are installed. Newer LED fixtures have better lighting optics that spreads the light into areas where that light is needed with lower losses in the fixtures themselves.
Newer generation LED lamps generate a better quality of light than MHs. LEDs can be selected or variably tuned to generate light in a range from warmer and softer to cooler and brighter. LEDs with higher color rendering index (CRI) ratings are better able to bring out colors and contrasts on objects and surfaces, which increases operating efficiency in work areas.
LED lamps require virtually no warm up time to come to full illumination, unlike MH lamps which can take 20 minutes or more to come to full brightness.
LEDs are safer because they operate at lower physical temperatures than MH lamps. An MH lamp that is scratched is prone to catastrophic failure, in which event the bulb itself could shatter, spreading around hot glass and components. LEDs have a relatively low physical operating temperature and are cool to the touch, thus substantially improving the safety of operating conditions.
With better fixture optics and diffusers, LED light can be targeted more directly onto areas where the light is intended to reach, with less light spilling over into neighboring environments. This reduces light pollution in areas abutting the surfaces that are intended to be lit.
MH bulbs include mercury vapor and care must be taken to dispose of them properly at the end of their operating lives. LEDs use no hazardous materials, thus reducing environmental burdens and the need for special waste handling applications.
LEDS are more tolerant to environmental extremes of high and low temperatures and precipitation conditions. Although some LEDs will exhibit weakened performance in extremely high temperature environments, new heat sink technology has improved that performance significantly.