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See also Compact Fluorescent Lamp Bulbs (CFL) in environment,
LED lights in products and Light Bulb size/dimensions nomenclature here.

Types - Incandescent, Compact Fluorescent Lamp (CFL) and Light emitting diode (LED) Bulbs

Luminous efficacy table
Light type Typical
luminous efficacy
Tungsten incandescent light bulb 12.5-17.5 lm/W
Halogen lamp 16-24 lm/W
Fluorescent lamp 45-75 lm/W
LED lamp 30-90 lm/W
Metal halide lamp 75-100 lm/W
High pressure sodium vapor lamp 85-150 lm/W
Low pressure sodium vapor lamp 100-200 lm/W
Mercury vapor lamp 35-65 lm/W
Source: How to convert lumens to watts (W)

Energy saving lamps have high luminous efficacy (more lumens per watt).

Lumens Incandescent
light bulb
 / LED
375 lm 25 W 6.23 W
600 lm 40 W 10 W
900 lm 60 W 15 W
1125 lm 75 W 18.75 W
1500 lm 100 W 25 W
2250 lm 150 W 37.5 W
3000 lm 200 W 50 W

Comparison of 65 watt (700-900 lumens) equivalent bulbs. Nov 2013
3 hours/day = 1,000 hrs/yr for 10 years (10,000 hrs) with an electric rate of $0.10/kWh.
Type Watts Lumens Life
Total Cost (10 yrs)1 Manufac-
Energy (MJ)
Bulbs Elect Total
Incandescent2 60 800-
1,000 $0.80 $8 $60 $68.00 10-106
Halogen 43 750 1,000
CFL3 15 900 8,500-
$1.25 $1.50 $15.00 $16.5011-521
LED3 8-12 800 25,000 $12.00 $12.00 $12.50 $24.5040-1,490
LED (2016)4 6-9 800 40,000 $65 $65 $5.80 $11.8026-484

Note: If you compute over the lifetime of the LED (23 yrs) the cost CFLs and LEDs is about the same.

1. You will see things like $200 savings over the life of the bulb on the package.
   This is over an expected life of 23 years and uses a cost of electricity of 15¢/kWh
   It does not take into account the time value of money. 
   i.e. a savings of $5 in 23 years is not worth as much as $5 today.
2. Incandescent: Edison type bulb. - Tungsten
3. LED's were dimmable, CFL's here were not. (There are dimmable CFLs)
4. Efficacy is expected to increase to 202 lm/W by 2015 (DOE). *
5. Projections for LED costs per 1,000 lumens (klm) in 2015 range from $2.20 to $6 *
   See LEDs Magazine - LED fabrication roadmap targets  LED prices of $2.20/klm by 2015
   According to Strategies Unlimited, the average manufacturing cost per klm has declined
   from $13 in 2011 to less $3.65 in Sept. 2013
6. Manufacturing Energy - The DOE in the report below adds manufacturing and packaging
  energy use in order to compare life-cycle energy savings.
  The numbers are Mega Joules (MJ)/20 million lumen-hours, so since it takes 
  22 incandescent bulbs to match the life of 1 LED they use the energy for 1 bulb X 22.
  This is very small compared to the energy consumed in using the bulb which is:
  15,000 MJ/20 million lumen-hours for incandescent and 4,000 MJ/20M l-h for CFL and LEDs
Source: Life-Cycle Assessment of Energy and Environmental Impacts of LED Lighting | DOE 
* In Oct. 2017 a PhilipsModel # 461137 (8.5W 800 lumens) 4 pack at Home Depot cost $7.97. for $2.50/Klumen.
and a 3 pack of 9W 750 lu Duracell Ultra at Batteries Plus Bulbs was $6.99 or $3/Klu.

Note: Other sources report life as: Incandescent = 2,000 hrs LEDs in electronics - 50,000 hrs LED household lighting bulbs - 25,000 hrs In August, 2013 Consumer Reports tested bulbs.
They looked at things like life, brightness, warm-up time, frequent on/off performance light distribution, efficiency, and color. In the general purpose 60 W equivalent category 6 out of 8 check rated bulbs were LEDs. In other categories 11 out of 15 check rated bulbs were LEDs. CFL's generally fell down in one of these categories: brightness, warm-up time, light distribution. Sample prices Nov. 2013 60W replacement bulbs
Type Costco Home Depot
Price Watts lu Dim7Price Watts lu Dim7
LED $11 13.5 850 y $13 12 800 y
CFL $1.25 13 900 n $1.75 14 800 n
CFL $1 14 800 n
7. Dim = Dimmable There are advantages of LEDs over CFLs other than cost.
e.g. CFL's take longer to reach full brightness especially in the cold (even a 65° room).
CFL's contain mercury.
LED's on the other hand tend to be flat and directional.
LEDs contain lead, arsenic and a dozen other potentially dangerous substances.

Color/Temperate: Different bulbs emit light of different colors in the light spectrum.
Color temperature relates to the fact that when an object is heated, it will emit a color that is directly related to the temperature of that object.
Traditionally incandescent bulbs emitted warmer colors and florescent bulbs cooler temperatures, but newer compact florescent bulbs and LED can be purchased in a range of temperatures.
See Light Spectrum.


 A19 - Common household light bulb shape
 CRI - Color Rendering Index
 CCT - Correlated color temperature
 CW - Cool White - 4000-5000K
 DOE - Department of Energy
 E12 - Candelabra Screw
 E26 - Standard (Medium) screw
 Energy Star qualified - Energy star for other appliances has to do with energy efficiency.
      For LED bulbs in also includes as a number of performance related metrics such as
      light distribution, durability, lumen maintenance and color quality.
      See Why Energy Star LED light bulbs are a rare breed |
 G25 - Global bulb shape
 HID - High-intensity discharge lamp - Mercury-vapor, Metal-halide, Sodium-vapor lamps
 klm - 1,000 lumens
 kWh - KillaWatt-hour
 LCA - Life-Cycle Assessment
 LED - light-emitting diode
 L-70 - Life = Time taken for the brightness to fall to 70% of its original value.
 Lumen (lm) - Measure of light brightness
 MJ - Mega Joule = 0.27 kWh
 OLED - organic light-emitting diodes 
 PLED - polymer light-emitting diodes
 RoHS - Restriction of Hazardous Substances
 S-6 Miniature standard shape 
 S-14 Standard bulb shape and size [14/8 in or 1 3/4 in diameter]
 SSL - Solid State Lighting - LED, OLED or PLED
 WW - Warm White - 2700-3500K 

Products: | For CFLs,LED lights,lighting,lighting lamps,light bulbs,lights and lighting,bulbs and lighting
EagleLight | LED Lights, LED Light Bulbs, LED Lighting
Where to get them on the LED page

Pages here:
Light Bulb size/dimensions nomenclature (socket types)
LED lights
Compact Fluorescent Bulbs
Light Spectrum
Compare: LED Lights vs CFL vs Incandescent Lighting Chart
Lighting Choices to Save You Money | Department of Energy
Life-cycle study shows current LED bulbs about on par with CFLs, but next-generation twice as good : TreeHugger
Energy Saving Compact Fluorescent Lamp Bulbs (CFL)
Life-Cycle Assessment of Energy and Environmental Impacts of LED Lighting | Department of Energy Products
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last updated 12 Nov 2013