Understanding HID Light Bulbs

If you are in the field of electricity and maintenance, or you need to do some electrical tasks in your home, it’s a good idea to familiarize yourself with different kinds of light bulbs. One type of light bulb that is particularly powerful is an HID (High-Intensity Discharge) light bulb. Read on to find out how these bulbs work and when it might be best to use them.

How the HID Light Bulbs Work

HID light bulbs have an arc that passes between two electrodes in a pressurized tube which causes various metallic additives to vaporize. The electricity enters through the base of the lamp and flows into the arc tube, which acts kind of like a sealed envelope that contains gas and metallic salts. The gas reacts with the electricity to heat up and vaporize the metallic salts. Then a roiling plasma is created, which can better be described as a chemical combustion that produces artificial light. This light is very powerful and can illuminate across long distances.

Note: HID light bulbs can be extremely dangerous if broken. The roiling plasma inside the arc tube can be hazardous if you are exposed to it and you could get a chemical burn if you’re anywhere near the light bulb when it bursts.

Uses of HID Bulbs

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Philips Lighting Standard 250-Watt ED28 E39 from USESI

So, obviously HID bulbs give off a very powerful light. Let’s look at some examples where a light like this may be used:

Street Lights: The original use for HID bulbs was so that they could light the street. However, in their first incarnation, they were mercury vapor whereas now they are more often metal halide and high-pressure sodium lamps.

Stadiums: A brightly lit stadium can use 60 HID lamps of 1,000 watts each to produce the illusion that night time games are being played in the middle of the afternoon.

Parking Garages: Also vast areas that tend to be unsafe, these garages need all the lighting they can get.

Retail Stores: Many retail stores rely on bright lighting to market their products to their customers. Ceramic metal halide HID lamps are often used.

HID Pros and Cons

If you are in a situation where you need to light a vast area, HID lights may be a good choice. But, there are both pros and cons to using them.

uses of hid light bulbsPros:

  • The HID light bulbs can throw a lot of light over long distances.
  • High-pressure sodium HID light bulbs cause relatively low amounts of pollution.
  • Low-pressure sodium lamps can also last a long time. This is why they are often used in businesses that keep their lights on around the clock.
  • HID’s are typically lower cost than the other.
  • HIDs can withstand extreme temperatures.


  • HID light bulbs are not as energy efficient as some of their competitors.
  • Over time, HID light bulbs color shift, turning blue, pink or purple.
  • Even though HID lights can last 20,000 hours, they often start to depreciate after about 10,000.
  • HID light is often fragile due to their moving parts, glass bulbs, and filaments.
  • Requires a 5-10 minute warm-up time.
  • HID lights are not dimmable.

If you are looking for an alternative to HID lighting, LED lighting would be an obvious choice. Although these lights are more expensive, there are virtually no maintenance expenses. LED lights tend to be more durable, longer lasting, dimmable and they turn on instantly. Considering these factors, one might wonder why the HID lights are still purchased. HIDs are still a good choice if you are looking for temporary, low-cost lighting, if you are dealing with extremely high-temperature applications, or if you want to match existing ballasts that are still in good shape.

Government Regulations

If you are using HID light bulbs, or any kind of HPS (High-Pressure Sodium) lighting, you should be aware that there may be government regulations involved. Certain districts may require that street lights have a high-pressure sodium kelvin temperature and a CRI (Color Rendering Index). If this is the case in your area, it is advisable to use an LED equivalent HPS which will give you the same color temperature and less light pollution but last longer and use less energy.

Although HID light bulbs may seem as if it is phasing out, it is still being used in certain applications. Because of the nature of the lighting, it is important to be aware of how it works, the best uses for it and some potential dangers. This way, HID light bulbs can be used in a safe and effective manner.