The Facts of Lighting
Light Source
|
 |
Average Life
(Hours)
|
 |
Lumens
per Watt
|
 |
 |
 |
|
Incandescent
|
750-2500
|
10-20
|
 |
 |
 |
|
Tungsten-Halogen
|
1000-3500
|
18-22
|
 |
 |
 |
|
Self Ballasted Mercury Vapor
|
12000-16000
|
25-33
|
 |
 |
 |
|
Mercury Vapor
|
24000
|
40-63
|
 |
 |
 |
|
Fluorescent
|
7500-24000
|
60-110
|
 |
 |
 |
|
Metal Halide
|
7500-24000
|
85-110
|
 |
 |
 |
|
High Pressure Sodium
|
24000
|
80-140
|
 |
 |
 |
|
Low Pressure Sodium
|
12000-18000
|
100-200
|
Some Additional Facts Of Lighting
One gallon of #6 fuel oil is required to produce 15 kilowatt-hours of electricity. This amount of power would be consumed by 150 100-watt incandescent lamps operating for one hour.
One watt of air conditioning is required to offset the heat of one watt of light. Thus energy-saving lamps reduce air conditioning cost watt-for-watt.
Fluorescent lamps produce approximately five times the light of standard incandescent lamps -- watt-for-watt.
High pressure sodium lamps produce more than twice the light of mercury vapor lamps -- watt-for-watt.
Low pressure sodium lamps are the most energy-efficient of all lamps, producing approximately three times the light of mercury vapor lamps -- watt-for-watt.