|Date||April 08, 2019|
Wanting to Upgrade to LED, but not sure what the difference is? Here is a quick guide to making the right LED Lighting choice.
The two technologies are entirely different methods of producing light. Metal halide bulbs contain metals that are evaporated into inert gas within the glass casing while LEDs are a solid state semiconductor technology. Both technologies produce a very high quality light. LEDs last much longer, more energy efficient and require less maintenance. Metal halides have long warm-up periods and a shorter lifespan. Both Metal Halide and High Pressure Sodium bulbs are part of the HID family of bulbs. The primary visual difference between them is that metal halide light is white and the light emitted from a High Pressure Sodium bulb is amber orange.
|Start Up||Metal Halides have longest warm-up time of any light source, usually around 20 minutes. This means their full output is not until they reach their normal operating temperature.||LED fittings are instantly at full output.||LED|
|Lifetime||Lifetime is around 6,000 - 15,000 Hours, depending on the manufacturer. Typical lifetime is 9,000 hrs.||LEDs last longer than any light source commercially available on the market. LEDs are typically 40,000 - 60,000 Hours.||LED|
|Directionality||Metal halide lights are omnidirectional. Omnidirectional lights produce light in 360 degrees. This is a large system inefficiency because at least half of the light needs to be reflected and redirected to the desired area being illuminated.||LED Chips are mounted on a circuit board, so depending on the configuration, usually 180 degrees. This is typically an advantage because light is usually desired over a target area (rather than all 360 degrees around the bulb).||LED|
|Colour Temperature||Metal halide lamps generate a very cool white light compared with other light sources, which has been a major benefit. They are available in color temperatures as low as 3000K.||LEDs are available in a wide range of colour temperatures, generally from 2700K-6000K (ranging from 'warm white' to 'daylight')||-|
|Colour Rendering Index (CRI)||Metal halides have traditionally been the best source of high CRI white light on the market. Some models are available in CRI>90.||LEDs are available in the full range of CRI values. Typically, LED is CRI>70, some even up to CRI 97.||-|
|Efficacy||Metal Halides lose out to LEDs because their system efficiency is much lower due to all of the losses associated with omnidirectional light output and the need to redirect it to a desired area. A typical Metal Halide Lamp is 115lm/W, with losses associated with the lamp holder and surround.||LEDs are very efficient relative to every lighting type on the market. Typical source efficiency ranges from 80 - 140 lm/W. Where LEDs really shine, however, is in their system efficiency (the amount of light that actually reaches the target area after all losses are accounted for).||LED|
|Shock Resistance||Metal halide bulbs are relatively fragile.||LEDs are solid state lights (SSLs) that are difficult to damage with physical shocks.||LED|
|Control||A shortcoming of metal halide lighting is that these lamps are not dimmable through electrical means. The dimming needs to be done using filters.||LEDs are easily dimmable, and Power Supplies are available to suit all dimming controls.||LED|