Just like buying eggs at the supermarket, buying light bulbs can turn into quite the task with the stupefying selection provided. Luckily, we have come up with an idea.
Luckily, we have come up with an idea. Here is a comparison of the light bulbs you are likely to purchase for your house or business, including their lifespans, energy efficiencies, and general workings — just don’t forget to check if it’s a bayonet or screw cap...
A household that invested $90 in changing 30 fixtures to [Compact Fluorescent Lights] would save $440 to $1,500 over the five-year life of the bulbs, depending on your cost of electricity. Look at your utility bill and imagine a 12% discount to estimate the savings."
- Money US News
Quick Links
Incandescents
Halogens
Fluorescent
Compact fluorescent lamps
Mercury-vapour lamps
LEDs
Edison bulbs
Light bulb comparison table
Incandescents
How common?
Let’s start with the basics: incandescent bulbs. These are your classic light bulbs that are in most houses and probably yours right now. These bulbs also feature commonly in torches and car headlights, not to mention in cartoons above heads with bright ideas.
How do they work?
They have a generic bulbous shape with a characteristic metal filament inside. This metal filament is made of tungsten and is a bridge for electricity to surge over. As the electrons flow over the filament, it heats up so much that it begins to emit light. This is comparable to heating up a cattle brander or other metal implement where it glows red and eventually white-hot. Well that’s your light: white hot (have you ever tried to change one while it was still on? Youch!).
Pros
Cons
Cheap to produce; cheap to buy
Short lifespan: ~1000 hours
Bright and pleasant warm light
Wasteful: 95% of energy is wasted as heat rather than light (which would be fine if it were a heater and not a ‘light’).
Bonus information
Incandescent bulbs are not as fire hazardous because there is no oxygen inside to catch alight — t’is a vacuum or some inert gas. Their ubiquity is owed to their cheap production costs. Incandescents are so wasteful that many countries are in the process of banning them. ‘Incandescence’ means to emit light from being heated. And since this process is so characteristically wasteful, it’s a helpful way to remember the name for these common, scorchy bulbs.
Halogens
How common?
Also known as ‘tungsten halogen lamps’, halogens are quite common. Because they can be made smaller than incandescents, they are used for smaller applications such as in penlights.
How do they work?
Halogens work similarly to incandescent bulbs, but instead of having a vacuum or some other gas inside the bulb, halogens contain...you guessed it, a halogen gas. Normally, the tungsten filament inside an incandescent evaporates, weakening the filament and eventually leading to a blown light. The halogen gas that fills the interior of halogens ‘feeds’ the tungsten filament, thus prolonging its lifespan.
Pros
Cons
Longer lifespan than incandescents
Extremely hot and thus fire hazardous
‘Whiter’ more outdoor-like light
Fluorescent
How common?
Fluorescents lamps or tubes are common. These are the ones that flicker in long corridors, largely in horror films.
How do they work?
These lamps use an entirely different process for light generation. Where incandescent lights heat metal up till they emit heat and light, fluorescents take advantage of a chemical reaction known as fluorescence.
Fluorescent lamps contains mercury gas at a low pressure. Electricity is ran through the system, exciting the mercury temporarily. The mercury calms down, emitting light on ‘its way down’.
Pros
Cons
Last quite long, 10x - 20x longer than incandescents
Artificial looking light
Efficient (convert ~22% of energy into light)
Cannot be dimmed
1/5th the heat of incandescents
Broken lights are toxic for you and the environment
Frequent usage can shorten lifespan considerably
Elongated and space consuming
Flicker a lot — bad for photography
Bonus information
Fluorescence occurs when a body with special properties absorbs energy and is boosted into another state before coming down again. This is analogous to letting go of a blown up balloon: it emits a farting sound (fluorescence) as it deflates once more to a stable state.
Compact Fluorescent Lamps (CFL)
How common?
These fluorescent lights are more efficient than regular fluorescents. Some are designed with a characteristic ‘helical’ or coiled pattern. They are increasing in popularity as their value and lifespan are increasingly recognised.
How do they work?
CFLs work the same as the tubular fluorescents, but they are more compact, with the tube coiled in to form a compact shape.
Pros
Cons
Long lifespan, 6,000-15,000 hours
Produce less light as they age
Energy efficient 1/7 -⅓ the power of incandescents
3-10x more expensive
Not as hot as incandescents
Not particularly compatible with dimming
Can interfere with infrared appliances such as TV remotes and phones
May not start in cold weather
Warm up time before optimal brightness
Contain mercury and emit UVs
Mercury-vapour lamps
How common?
Common, but not in the household. These are the bulbs that line the streets on streetlights. They are in the process of being banned worldwide due to their poor efficiency.
How do they work?
They also work by exciting mercury vapour inside an enclosed bulb.
Pros
Cons
Very long lifetime — 24,000 hours
Casts ‘creepy’ light, distorting colouration
High intensity white light
Can take over 5 minutes to turn on
Can emit harmful UV radiation
LEDs
How common?
Light-emitting diodes are very common, but not commonly as a lighting source. LEDs are a common component of circuitry such as remotes, traffic lights, and camera flashes.
How do they work?
LEDs utilise a process known as electroluminescence, using a material known as a semiconductor. Electrons are ‘coaxed’ to enter electron holes within the semiconductor, thus becoming excited and emitting light.
Pros
Cons
Can be tiny (a mm2)
More expensive than most types of lighting
Lower energy consumption
Cold light
Longer lifetimes: 25,000-100,000 hours
Robust
Flexible colour options, simply
Easily dimmable
Bonus information
The first LED was only developed in the 60s. LEDs were mostly red. When the blue LED was finally developed, the inventors were awarded the Nobel Prize in 2014. And though LEDs seem modern or new, they’ve been around for 60 years.
Edison bulbs
How common?
Not very. These bulbs have long and characteristic filaments, giving a vintage look.
How do they work?
Edison or vintage bulbs are incandescents. LED imitations are being produced to maintain the look of these globes, but upkeep the energy efficiency and longevity of LEDs.
Pros
Cons
Cheap
Inefficient
Look nice
Short lifespan
Hot
Bonus information
Edison bulbs began their resurgence in the 80s.
There you have it. To find the best light bulb for your household consider how often you turn on and off your switches (affecting their lifespans), and which type of light you’d like: warm, cool, natural white. Now next time you stumble into the formidable light bulb aisle you’ll have a much better idea!
Light bulb comparison table
Measurement
Incandescent
Halogen
Fluorescent
LED (Generic)
Electrical power (W)
60
42
14
10
Light output (lm)
860
650
800
800
Luminous efficacy (lm/W)
14.3
14.42
57.14
80
Color temperature (K)
2700
3100[96]
2700
3000
CRI (Colour fidelity; 100 = natural colouration)
100
100
>75
>85
Lifespan (hours)
1,000
2,500
8,000
+25,000
*Source: Wikipedia
The post Light Bulb Comparison appeared first on finder.com.au.