Light source efficiency l m / w (lumen efficiency)
The efficiency of a light source depends on the lumen of the light it emits divided by the power consumption

L E D brightness is not similar to wattage (W) measurement, but measured in lumens output (l m) 
Decide. Electricity is 85% longer.
iLighting L E D Lumen has high lumen efficiency, and it also has obtyained European A + energy label to ensure power saving and environmental protection.