LED chips typically consume 80% less power than a halogen of equivalent brightness.
What are lumens?
The total light output from a light source, regardless of the direction the light travels, is specified as lumens (lm), where 1 lumen is defined as equivalent to the light output from 1 candle. This figure is used to describe and compare lamp brightness.
What is efficacy?
Efficacy (lm/w) is the total light output in lumens per watt of power consumed. The higher the lumens per watt, the more efficient a light source is. The efficacy specification is simple to calculate. For example, a LED globe that produces 720 lumens from 10 watts has an efficacy of 72 lumens per watt (720 lumens/10 watts).
How efficient are LED lights?
The following table shows the power consumption of a LED light is typically 80% less than a halogen of equivalent brightness:
A Comparison of Light Types
|Incandecent||60 watts||770 lm||13 lm/w|
|Halogen||50 watts||750 lm||15 lm/w|
|CFL||11 watts||740 lm||65 lm/w|
|LED||10 watts||720 lm||72 lm/w|
What is lux?
Lux (lx), is defined as the level of brightness at a particular distance from the light source. 1 lux is equivalent to 1 lumen per square meter, so if you measured 800 lux at 1.5m height using a lux meter, then there is 800 lumens of light per square meter at 1.5m.