You might not realize it, but you probably interact with HID light bulbs every day. Because of their bright and powerful light, HIDs are normally used in streetlights like in parking lots or parking garages. They’re also found in gyms and sports stadiums. A lot of warehouses or factories use HIDs, plus some retail stores.
HIDs were partly to blame for the 30-minute delay during Super Bowl 47 between the Baltimore Ravens and the San Francisco 49ers. But with so many other Super Bowl blips, we forgive you if you’ve already forgotten about the 34-minute blackout for half of the stadium. (By the way, the Ravens won that one 34-31.)
It’s important to note that HIDs are the only other lamp type, besides fluorescents, that require a ballast. Before you buy HID light bulbs, it’s always important to check the ballast compatibility.
How do HID light bulbs work?
HID stands for high intensity discharge. Electricity enters an HID lamp at the base and flows into a sealed glass envelope (the arc tube) which contains gas and metallic salts. The gas helps with the initial strike of light. The gas then heats up and vaporizes the metallic salts. Next a roiling plasma is created. That’s like a chemical combustion that produces artificial light.
This is what the inside of the light bulb looks like:
You can see where the arc tube is located. That tube passes between two electrodes in a pressurized tube, causing various metallic additives to vaporize and release large amounts of light.
The result can be a very high wattage. HIDs are known to have a wattage up to 1,000.
Types of HID light bulbs
There are four different types of HID light bulbs.
- High pressure sodium (HPS): This type of HID is typically used for outdoor security lighting, like streetlight and parking garages, or other areas where light color is not a concern. High pressure sodium HID light bulbs typically have a warm, golden color. High pressure sodium HID light bulbs are a popular option because they have limited pollution compared to LED and metal halide.
- Low pressure sodium: Low pressure sodium HIDs are known for their terrible color quality. What a thing to be remembered by, right? But despite their bad light quality, they last for a very long time. Low pressure sodium HIDs are commonly used in factories that need minimal light but where lights are on 24/7.
- Mercury vapor: This is the oldest type of HID light bulb and was invented for streetlights. But these days, they are rarely produced in the U.S. and often replaced by metal halide or high pressure sodium (HPS) light bulbs.
- Metal halide: Metal halides are the most versatile type of HID lamp, so they are the most commonly used. Unlike other HIDs, metal halides have a higher color rendering index (CRI). That means they work great indoors in retail stores, or outdoors like for stadiums or security lighting.
The type of base on the light bulb depends on the type of HID. Because of their high wattage, most HID light bulbs have either a medium or mogul base. Some ceramic metal halides may have a pin base.
With HIDs, you might also have to consider whether it’s a base up or base down light bulb. A base up HID is what it sounds like. You insert the light bulb with the base up. For a base down HID light bulb, you insert the light bulb with the base down. This is a critical distinction because the light bulb will not work in the wrong base orientation.
Where can I use HID light bulbs?
Because they throw out so much light, HIDs are commonly used in areas where safety is a primary concern.
Here are some applications where you will typically find HIDs:
- High-bay fixtures in a warehouse, parking garages, or outdoor pole lighting
- Industrial fixtures in a gym
- Reflector lighting in some retail locations
HID light bulbs and ballast compatibility
We mentioned that HIDs run off a ballast. That’s where electricity typically enters the fixture. The starter inside the ballast provides the initial high-voltage jolt of electricity and that ignites the HID bulb. Then, once the light bulb is fully lit, the ballast regulates the electrical current.
There are two types of ballasts: magnetic and electronic. Magnetic ballasts are used for high pressure sodium light bulbs and for some metal halide light bulbs. Electronic ballasts are more versatile and more common today.
Recycling HID light bulbs
HID light bulbs contain mercury, so you need to recycle them as you replace them. Mercury can be dangerous if it's released into the environment, such as when light bulbs hit the landfill instead of a recycling center. All types of HIDs include mercury, like metal halide, mercury vapor, and high-pressure sodium light bulbs. You can buy boxes for proper disposal by clicking here.
Questions about HID light bulbs
Our goal at Regency Lighting is to make your lighting decisions easier. If you are confused about which products you need or you have any questions, we are here to help. You can send us a message, call us, or use the chat in the bottom right corner of your screen. We also have seven sales and distribution locations across the U.S. to better serve your lighting needs.