10 - 20 LPW
15 - 25 LPW
20 - 33 LPW
40 - 60 LPW
55 - 80 LPW
60 - 105 LPW
80 - 105 LPW
90 - 105 LPW
65 - 140 LPW
150 - 200 LPW

The number of lumens you get for every watt consumed (called LPW or Lumens per Watt) is a measure of how efficient a light source is in converting electrical energy into light.

Lumens per Watt for lamps is like miles per gallon for a car. The higher the efficacy, the better the lamp is from an energy viewpoint.

Incandescent and halogen are the lowest efficacy sources, but they have other qualities that make them popular. Fluorescent and HID sources are very efficient.