Street lights play a key role in making our roads and paths safer at night. They help drivers see better and make walking around after dark less scary. Different types of street lights include LED, high-pressure sodium, metal halide, and solar-powered options. Each kind has its own good points and not-so-good points.
This article will look at the main types of street lights you might see in your town or city. We’ll compare how long they last, how much energy they use, and how well they light up the area. By the end, you’ll have a good idea of which street lights work best for your places.
Incandescent
Incandescent street lights use a heated filament to produce light. You’ll find them cheap to buy but costly to run. They burn out quickly and use lots of energy.
These lights give off a warm, natural glow. Colors look great under them. But they’re not efficient for lighting large areas.
You might see incandescent lights in old neighborhoods or historic districts. They’re good for creating a nostalgic feel.
- Advantages
- Low initial cost
- Simple technology
- Disadvantages
- High energy consumption
- Short lifespan
- Light efficacy and CRI
- Efficacy: 10-17 lumens per watt
- CRI: 100 (excellent color rendering)
Halogen
Halogen lights are like souped-up incandescent bulbs. They use halogen gas to make the light brighter and last longer.
You get a crisp, white light from halogen bulbs. They’re brighter than regular incandescent lights. But they still use more energy than newer options.
These lights work well for spotlighting or flood lighting. You might see them lighting up building facades or parking lots.
- Advantages
- Brighter light
- Longer lifespan than incandescent
- Disadvantages
- Higher energy consumption than modern alternatives
- Generates heat
- Light efficacy and CRI
- Efficacy: 16-24 lumens per watt
- CRI: 100 (excellent color rendering)
Fluorescent
Fluorescent street lights use mercury vapor and a phosphor coating to create light. You’ll find them in many indoor spaces.
These lights save energy compared to incandescent bulbs. They last longer too. But the light quality isn’t as nice.
You’ll often see fluorescent lights in parking garages or covered areas. They work well in places that need constant light.
- Advantages
- Energy-efficient
- Longer lifespan than incandescent
- Disadvantages
- Contains mercury
- Lower light quality
- Light efficacy and CRI
- Efficacy: 35-100 lumens per watt
- CRI: 60-90 (varies by phosphor coating)
Compact Fluorescent Light (CFL)
CFLs are small fluorescent lights. They fit in spaces made for regular bulbs.
You save energy with CFLs. They last longer than old-style bulbs. But the light can seem a bit harsh.
These lights work well in small outdoor fixtures. You might use them on porches or in yard lights.
- Advantages
- Energy-efficient
- Longer lifespan than incandescent
- Disadvantages
- Contains mercury
- Lower light quality
- Light efficacy and CRI
- Efficacy: 50-70 lumens per watt
- CRI: 80-90 (good color rendering)
Mercury Vapor
Mercury vapor street lights use mercury to make bright light. They’ve been around for a long time.
You get a lot of light from these bulbs. They last a while too. But the light looks bluish-green and makes colors look weird.
These lights often show up in big outdoor areas. You might see them in industrial zones or large parking lots.
- Advantages
- High light output
- Long lifespan
- Disadvantages
- Contains mercury
- Poor color rendering
- Light efficacy and CRI
- Efficacy: 25-60 lumens per watt
- CRI: 15-50 (poor color rendering)
High-Pressure Sodium (HPS)
HPS lights use sodium vapor under high pressure. They’re super efficient.
You save a lot of energy with HPS lights. They last a long time too. But everything looks orange under them.
These lights are common on highways and in parking lots. You can spot them by their yellow-orange glow.
- Advantages
- Very energy-efficient
- Long lifespan
- Disadvantages
- Poor color rendering
- Warm yellow light
- Light efficacy and CRI
- Efficacy: 50-150 lumens per watt
- CRI: 20-30 (poor color rendering)
Low Pressure Sodium (LPS)
LPS lights use sodium vapor at low pressure. They’re the most efficient street lights.
You save the most energy with LPS lights. They last forever. But they only produce yellow light.
These lights work well on roads and for security. You’ll know them by their pure yellow glow.
- Advantages
- Extremely energy-efficient
- Long lifespan
- Disadvantages
- Very poor color rendering
- Monochromatic yellow light
- Light efficacy and CRI
- Efficacy: 80-180 lumens per watt
- CRI: -44 (very poor color rendering)
Metal Halide
Metal halide lights use metal salts to create light. They’re bright and show colors well.
You get good light quality from metal halide bulbs. They’re pretty efficient too. But they take a while to warm up.
These lights often light up sports fields and big outdoor areas. You might see them in stadiums or parks.
- Advantages
- High light output
- Good color rendering
- Disadvantages
- Higher energy consumption than LEDs
- Shorter lifespan
- Light efficacy and CRI
- Efficacy: 65-115 lumens per watt
- CRI: 60-90 (good color rendering)
Ceramic Discharge Metal Halide Lamp
These lights are fancy metal halide lamps. They use ceramic instead of quartz.
You get great color and efficiency from these lights. They last longer than regular metal halide bulbs. But they cost more.
You might find these lights in high-end outdoor spaces. They’re good for places where color matters, like gardens or art displays.
- Advantages
- Better color rendering
- Higher efficiency
- Disadvantages
- Higher cost
- Requires ballast
- Light efficacy and CRI
- Efficacy: 80-120 lumens per watt
- CRI: 80-96 (excellent color rendering)
Induction Lamp
Induction lamps use magnetic fields to create light. They’re high-tech and long-lasting.
You won’t need to change these bulbs often. They’re efficient and work well in cold weather. But they’re pricey and hard to find.
These lights work well in hard-to-reach places. You might see them on tall poles or in industrial settings.
- Advantages
- Long lifespan
- High efficiency
- Disadvantages
- Higher initial cost
- Limited availability
- Light efficacy and CRI
- Efficacy: 60-90 lumens per watt
- CRI: 80-90 (good color rendering)
LED Street Lights
LED lights use tiny electronic chips to make light. They’re the newest and most efficient option.
You save tons of energy with LEDs. They last for years and give off great light. But they cost more up front.
These lights are taking over cities worldwide. You’ll see them on streets, in parks, and lighting up buildings.
- Advantages
- Very energy-efficient
- Long lifespan
- Excellent color rendering
- Disadvantages
- Higher initial cost
- Potential for blue light pollution
- Light efficacy and CRI
- Efficacy: 80-200 lumens per watt
- CRI: 70-90 (good to excellent color rendering)
Phosphor-Converted Amber (PCA) LED Lights
PCA LEDs turn blue light into amber. They’re a special kind of LED.
You get warm light that’s easy on the eyes. These lights are good for animals and star-gazing. But they cost more than regular LEDs.
These lights work well in neighborhoods and nature areas. You might see them in places trying to cut light pollution.
- Advantages
- Reduced blue light pollution
- Good color rendering
- Disadvantages
- Higher cost
- Slightly lower efficiency than standard LEDs
- Light efficacy and CRI
- Efficacy: 70-150 lumens per watt
- CRI: 80-90 (good color rendering)
Narrow-Band Amber (NBA) LED Lights
NBA LEDs make pure amber light. They’re designed to be wildlife-friendly.
You get light that doesn’t bother animals or block out stars. These lights are super specific in their use. But they don’t show colors well.
You’ll find these lights in sensitive wildlife areas. They’re also used in places with strict dark sky rules.
- Advantages
- Minimal blue light pollution
- Good for wildlife areas
- Disadvantages
- Higher cost
- Limited color rendering
- Light efficacy and CRI
- Efficacy: 60-140 lumens per watt
- CRI: 50-70 (moderate color rendering)
